用粗壮脉纹胞菌分别复合东方伊莎酵母、里氏木霉、绿色木霉、乳酸杆菌固态发酵已去除茶皂素的茶粕,通过测定发酵产物中3种纤维素酶:外切葡聚糖酶(C1)、内切葡聚糖酶(Cx)、β-葡萄糖苷酶(β-G)及总酶滤纸酶(filter paper activity,FPA)...用粗壮脉纹胞菌分别复合东方伊莎酵母、里氏木霉、绿色木霉、乳酸杆菌固态发酵已去除茶皂素的茶粕,通过测定发酵产物中3种纤维素酶:外切葡聚糖酶(C1)、内切葡聚糖酶(Cx)、β-葡萄糖苷酶(β-G)及总酶滤纸酶(filter paper activity,FPA)的酶活力来探讨其分解粗纤维素的协同作用。粗壮脉纹胞菌和绿色木霉混合发酵产生的C1酶酶活力较粗壮脉纹胞菌单菌发酵提高了51.09%,粗壮脉纹胞菌和绿色木霉复合发酵较单菌发酵延长了其纤维素酶分泌的周期,96 h时FPA酶活力达到2.782 U/g;粗壮脉纹胞菌复合里氏木霉、绿色木霉混合发酵组在发酵10 d后对茶粕粗纤维的最终降解率分别达到了64.19%和61.59%;接种量对单菌和混合菌发酵产纤维素酶影响总体趋势是随着接种量增加酶活力提高,但粗壮脉纹胞菌单菌发酵纤维素酶酶活力在接种量超过9 mL/100 g后开始下降。表明粗壮脉纹胞菌复合里氏木霉、绿色木霉混合发酵降解纤维素具有协同作用。展开更多
The measurement of specific-locus mutations in various eukaryotic organismshas been used as a mechanism to estimate the genetic consequences of humanexposure to environmental mutagens.Specific-iocus assays are usually...The measurement of specific-locus mutations in various eukaryotic organismshas been used as a mechanism to estimate the genetic consequences of humanexposure to environmental mutagens.Specific-iocus assays are usually confined tosingle genes and measure various types of genetic damage ranging from single base-pair substitutions to multilocus deletions.Not all such assays measure the samerange of genetic damage.Thus.different specific-locus assays may provide differentdata,both quantitative and qualitative.as a result of exposure to the sameenvironmental mutagen.The specific-locus assay in the ad-3 region of Neurosporacrassa measures genetic damage at 2 closely linked loci as well as other loci in thegenome.As a result.this assay permits a comprehensive evaluation of the types ofgenetic damage produced by different environmental mutagens.In this paper.thespectrum of genetic damage that can be detected in Neurospora is reviewed andcompared with other eukaryotic systems.展开更多
[Objective] This study aimed to investigate the regulatory mechanisms of carotenoid biosynthesis in Neurospora crassa. [Method] Gene knockout mutants pro- ducing less carotenoid were screened from 6 087 mutants; the y...[Objective] This study aimed to investigate the regulatory mechanisms of carotenoid biosynthesis in Neurospora crassa. [Method] Gene knockout mutants pro- ducing less carotenoid were screened from 6 087 mutants; the yield of carotenoid and asexual spore was measured; finally fluorescent quantitative real-time PCR was adopted to analyze the transcription of genes related to carotenoid synthesis and asexual sporulation, [Result] Six knockout mutants produced less carotenoid. In one of them, the yield of both carotenoid and asexual spore reduced, because the gene which encodes an ATP-dependent chromatin remodelling complex ATPase chain ISW1 was knocked out. This gene was named /ca-1 in this study. And the /ca-1 deletion result- ed in a reduction of 88% in conidial production and a decrease of 81% in carotenoid production. [Conclusion] The Ica-1 positively regulates the carotenoid syn- thesis and asexual sporulation in N. crassa.展开更多
Objective: To report the experience in the diagnosis and treatment of post traumatic pseudoaneurysms and arteriovenous fistulas. Methods: A series of 30 patients (11 women and 19 men) with posttraumatic pseudoaneurysm...Objective: To report the experience in the diagnosis and treatment of post traumatic pseudoaneurysms and arteriovenous fistulas. Methods: A series of 30 patients (11 women and 19 men) with posttraumatic pseudoaneurysms were reviewed retrospectively. Among them 7 patients (5 women and 2 men) were associated with arteriovenous fistula. Results: The causes included sharp penetrating trauma (18 cases), blunt trauma (6 cases) and iatrogenic arterial injury (6 cases). The main clinical manifestations consisted of local pulsatile mass (26 cases), vascular bruits (19 cases), thrill (13 cases), ischemia of distal limb (9 cases), neuropathy (5 cases) and pseudoaneurysm rupture (2 cases). All patients underwent surgery. The operations included: ligation of the vessels (12 cases), surgical resection and primary suture repair of the vascular defect or anastomosis (11 cases), vascular reconstruction with autogenous saphenous vein (3 cases) and synthetic vascular graft (4 cases). Conclusions: Because of the imminent clinical course, early operation is usually indicated. The operative treatment is effective and safe for most of the patients with post traumatic pseudoaneurysms and arteriovenous fistulas.展开更多
Models of circadian genetic oscillators involving interlinked feedback processes in molecular level genetic networks in Drosophila melanogaster and Neurospora crassa are studied, and mechanisms whereby synchronization...Models of circadian genetic oscillators involving interlinked feedback processes in molecular level genetic networks in Drosophila melanogaster and Neurospora crassa are studied, and mechanisms whereby synchronization can arise in an assembly of cells are examined. The individual subcellular circadian oscillatory processes are stochastic in nature due to the small numbers of molecules that are involved, and are subject to large fluctuations. The authors investigate and present the simulations of the stochastic dynamics of ensembles of clock-regulating proteins in different nuclei that communicate via ancillary small molecules, environmental parameters, additive cellular noise, or through diffusive processes. The results show that the emergence of collective oscillations is a macroscopic observable which has its origins in the microscopic coupling between distinct cellular oscillators.展开更多
文摘The measurement of specific-locus mutations in various eukaryotic organismshas been used as a mechanism to estimate the genetic consequences of humanexposure to environmental mutagens.Specific-iocus assays are usually confined tosingle genes and measure various types of genetic damage ranging from single base-pair substitutions to multilocus deletions.Not all such assays measure the samerange of genetic damage.Thus.different specific-locus assays may provide differentdata,both quantitative and qualitative.as a result of exposure to the sameenvironmental mutagen.The specific-locus assay in the ad-3 region of Neurosporacrassa measures genetic damage at 2 closely linked loci as well as other loci in thegenome.As a result.this assay permits a comprehensive evaluation of the types ofgenetic damage produced by different environmental mutagens.In this paper.thespectrum of genetic damage that can be detected in Neurospora is reviewed andcompared with other eukaryotic systems.
基金Supported by the National Natural Science Foundation of China (31000551 30970127)~~
文摘[Objective] This study aimed to investigate the regulatory mechanisms of carotenoid biosynthesis in Neurospora crassa. [Method] Gene knockout mutants pro- ducing less carotenoid were screened from 6 087 mutants; the yield of carotenoid and asexual spore was measured; finally fluorescent quantitative real-time PCR was adopted to analyze the transcription of genes related to carotenoid synthesis and asexual sporulation, [Result] Six knockout mutants produced less carotenoid. In one of them, the yield of both carotenoid and asexual spore reduced, because the gene which encodes an ATP-dependent chromatin remodelling complex ATPase chain ISW1 was knocked out. This gene was named /ca-1 in this study. And the /ca-1 deletion result- ed in a reduction of 88% in conidial production and a decrease of 81% in carotenoid production. [Conclusion] The Ica-1 positively regulates the carotenoid syn- thesis and asexual sporulation in N. crassa.
文摘Objective: To report the experience in the diagnosis and treatment of post traumatic pseudoaneurysms and arteriovenous fistulas. Methods: A series of 30 patients (11 women and 19 men) with posttraumatic pseudoaneurysms were reviewed retrospectively. Among them 7 patients (5 women and 2 men) were associated with arteriovenous fistula. Results: The causes included sharp penetrating trauma (18 cases), blunt trauma (6 cases) and iatrogenic arterial injury (6 cases). The main clinical manifestations consisted of local pulsatile mass (26 cases), vascular bruits (19 cases), thrill (13 cases), ischemia of distal limb (9 cases), neuropathy (5 cases) and pseudoaneurysm rupture (2 cases). All patients underwent surgery. The operations included: ligation of the vessels (12 cases), surgical resection and primary suture repair of the vascular defect or anastomosis (11 cases), vascular reconstruction with autogenous saphenous vein (3 cases) and synthetic vascular graft (4 cases). Conclusions: Because of the imminent clinical course, early operation is usually indicated. The operative treatment is effective and safe for most of the patients with post traumatic pseudoaneurysms and arteriovenous fistulas.
文摘Models of circadian genetic oscillators involving interlinked feedback processes in molecular level genetic networks in Drosophila melanogaster and Neurospora crassa are studied, and mechanisms whereby synchronization can arise in an assembly of cells are examined. The individual subcellular circadian oscillatory processes are stochastic in nature due to the small numbers of molecules that are involved, and are subject to large fluctuations. The authors investigate and present the simulations of the stochastic dynamics of ensembles of clock-regulating proteins in different nuclei that communicate via ancillary small molecules, environmental parameters, additive cellular noise, or through diffusive processes. The results show that the emergence of collective oscillations is a macroscopic observable which has its origins in the microscopic coupling between distinct cellular oscillators.