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1.
We studied in batch reactors the kinetics and characterization of 70 °C, volatile fatty acids (VFAs)-grown, upflow anaerobic sludge blanket granular sludge with 55 and 35 °C sludge as reference. The half-saturation constant (K s), the inhibition constant (K i), the maximum specific methane production rate (μCH4max), and the inhibition response coefficient (n) of the 70 °C sludge were 6.15 mM, 48.2 mM, 0.132 h−1, and 2.48, respectively, while no inhibition occurred at 55 and 35 °C, where the K s was 3.67 and 3.82 mM, respectively. At 70 °C, the highest initial specific methanogenic activity (ISMA, 0.311 gCH4-COD per gram volatile solids per day) on VFAs was about 12–15% lower than that on acetate and three to four times less than the ISMA for the 55 and 35 °C sludge. In the acetate conversion study, residual acetate (79 mg l−1) at 70 °C was three to five times higher than that at 55 and 35 °C. Further, the methane produced as percentage of the acetate consumed at 70 °C (89%) was lower than that at 55 (95%) and 35 °C (97%). At 70 °C, 10% of the ISMA remained after 15 days of starvation as compared to 26% (55 °C) and 92% (35 °C) after 30 days of starvation. Thus, the kinetics of the 70 °C granular sludge seem to differ from those at 55 and 35 °C. Received: 1 February 1999 / Accepted: 20 March 1999  相似文献   

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Human neurodegenerative disorders such as Alzheimer’s disease, Parkinson’s disease, and amyotrophic lateral sclerosis have been termed “protein misfolding disorders.” Upregulation of heat shock proteins that target misfolded aggregation-prone proteins has been proposed as a potential therapeutic strategy to counter neurodegenerative disorders. The heat shock protein 70 (HSP70) family is well characterized for its cytoprotective effects against cell death and has been implicated in neuroprotection by overexpression studies. HSP70 family members exhibit sequence and structural conservation. The significance of the multiplicity of HSP70 proteins is unknown. In this study, coimmunoprecipitation was employed to determine if association of HSP70 family members occurs, including Hsp70B′ which is present in the human genome but not in mouse and rat. Heteromeric complexes of Hsp70B′, Hsp70, and Hsc70 were detected in differentiated human SH-SY5Y neuronal cells. Hsp70B′ also formed complexes with Hsp40 suggesting a common co-chaperone for HSP70 family members.  相似文献   

4.
目的:研究清胰利胆颗粒对重症急性胰腺炎患者血清高迁移率族蛋白1(HMGB1)、热休克蛋白70(HSP70)、热休克蛋白27(HSP27)、白介素-8(IL-8)水平的影响。方法:选取2015年8月至2016年7月我院收治的84例重症急性胰腺炎患者,根据随机数字法分为观察组和对照组,42例每组。对照组采取常规方案完成治疗,观察组在此基础上使用清胰利胆颗粒治疗。比较两组患者临床疗效,血淀粉酶恢复至正常时间、白细胞恢复至正常时间、胃肠功能恢复至正常时间、腹痛缓解时间及血清HMGB1、HSP70、HSP72、IL-8水平。结果:治疗后,观察组临床总有效率显著高于对照组[92.86%(39/42)比71.43%(30/42)](P0.05)。观察组的血淀粉酶恢复至正常时间、白细胞恢复至正常时间、胃肠功能恢复至正常时间及腹痛缓解时间显著短于对照组(P0.05)。治疗前,两组患者HMGB1、HSP70、HSP72、IL-8水平比较无显著差异(P0.05),治疗后,两组患者HMGB1、HSP70、HSP72、IL-8水平和治疗前相比显著下降(P0.05),和对照组相比,观察组的HMGB1、HSP70、HSP72、IL-8水平较低(P0.05)。结论:清胰利胆颗粒能有效降低重症急性胰腺炎患者血清HMGB1、HSP70、HSP27、IL-8水平,且可提高临床疗效。  相似文献   

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为了探究中国南瓜(Cucurbita moschata)热激蛋白70基因的功能,该研究采用转录组测序和RT PCR方法,从中国南瓜中分离获得3个HSP70基因的开放阅读框(ORF)全长,分别命名为CmHSP70 1、CmHSP70 2和CmHSP70 3,三者的序列长度分别为1 998、1 941和2 118 bp,编码666、647和706个氨基酸。蛋白序列分析显示,3个CmHSP70蛋白均属于亲水性蛋白,都含有典型的NBD和SBD保守结构域;CmHSP70 1蛋白含有信号肽和跨膜结构,亚细胞主要定位于内质网;CmHSP70 2蛋白和CmHSP70 3蛋白不含信号肽和跨膜结构,亚细胞主要定位于细胞质和叶绿体。同源比对和进化分析发现,3个CmHSP70蛋白与苦瓜、甜瓜和黄瓜的HSP70蛋白的相似性最高且遗传距离最近。qRT PCR分析显示,42 ℃处理能够诱导3个CmHSP70基因在根、茎、嫩叶和成熟叶中表达,并且表达量存在明显的组织特异性,成熟叶中基因的表达量最高;高温条件下,成熟叶中3个CmHSP70基因均能够在短时间内(处理0~2 h)响应热胁迫而大量表达,尤其是CmHSP70 2基因,推测该基因可能在中国南瓜热胁迫过程发挥重要的调节作用。该研究结果为深入了解HSP70基因功能以及阐明中国南瓜的耐热机制提供理论依据。  相似文献   

6.
张颖  贾芸  吕军 《生物物理学报》2007,23(6):475-481
应用多样性增量结合二次判别分析(Increment of Diversity with Quadratic Discriminant analysis,IDQD)方法,对大肠杆菌σ^70启动子进行识别。使用受试者操作特性(receiver operating characteristic,ROC)曲线和精度召回率曲线(Precision Recall Curves,PRC)进行性能评估。10-fold交叉检验给出,在正负集之比为1:1时,ROC曲线下面积和PRC曲线下面积均为95%。结果表明,IDQD算法有能力应用于原核启动子的识别。识别精度高于现有算法。  相似文献   

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本文报告一例45,X/46,XXr嵌合体。患者徐××,表型女性,25岁,未婚。继发闭经,因阴蒂肥大而要求入院手术,维持女性。术中发现子宫为幼儿型,小而薄。右侧卵巢和输卵管缺如。左侧圆韧带薄而松弛。左侧输卵管长度正常但很细,卵巢小而薄。  相似文献   

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HSP70 family members are highly conserved proteins that function as molecular chaperones. Their principle role is to aid protein folding and promote the correct cellular localisations of their respective substrates. The function of HSP70 isoforms can be exhibited independently or with the HSP90 chaperone system in which HSP70 is important for substrate recruitment. In addition to their chaperone role, HSP70 isoforms promote cell survival by inhibiting apoptosis at multiple points within both the intrinsic and extrinsic cell death pathways. Consistent with this cytoprotective function, increased expression of HSP70 isoforms is commonly associated with the malignant phenotype. We recently reported that dual silencing of the major constitutive (HSC70) and inducible (HSP72) isoforms of HSP70 in cancer cells could phenocopy the effects of a pharmacologic HSP90 inhibitor to induce proteasome-dependent degradation of HSP90 client proteins CRAF, CDK4 and ERBB2. This was accompanied by a G1 cell cycle arrest and extensive apoptosis which was not seen in non-tumorigenic human cell lines. Here we discuss the possible implications of our research for the development of HSP70 family modulators which offer not only the possibility of inhibiting HSP70 activity but also the simultaneous inhibition of HSP90, resulting in extensive tumour-specific apoptosis.  相似文献   

11.
Saponification of the bis(carbamic acid ester) 1,3-C6H4(CMe2NHCO2Me)2 (1), made by the addition of methanol to commercial 1,3-C6H4(CMe2NCO)2, yielded the meta-phenylene-based bis(tertiary carbinamine) 1,3-C6H4(CMe2NH2)2 (2). Dinuclear [{(η4-1,5-C8H12)RhCl}2{μ-1,3-C6H4(CMe2NH2)2}] (3) resulted from the action of 2 on [{(η4-1,5-C8H12)Rh(μ-Cl)}2] in toluene. Combination of 2 with PdCl2 or K2[PdCl4] gave the dipalladium macrocycle trans,trans-[{μ-1,3-C6H4(CMe2NH2)2}2(PdCl2)2] (4) along with cyclometalated [{2,6-C6H3(CMe2NH2)2NC1N′}PdCl] (5). Substitution of PEt3 for the labile chlorido ligand of 5 afforded [{2,6-C6H3(CMe2NH2)2NC1, κN′}Pd(PEt3)]Cl (6). The crystal structures of the following compounds were determined: bis(carbamic acid ester) 1, ligand 2 as its bis(trifluoroacetate) salt [1,3-C6H4(CMe2NH3)2](O2CCF3)2, 2 · (HAcf)2, complexes 3 and 6, as well as 1,3-C6H4(CMe2OH)2 (the diol analogue of 2).  相似文献   

12.
Prostaglandins A2, E1, E2, methylated E2s and F2α affected erythropoiesis and/or erythropoietin (Ep) production. This action is indicated in the exhypoxic, polycythemic mouse where radioiron incorporations into RBC increased after administration of these compounds. The kidney and liver have been indicated through previous studies, to actively participate in Ep production. By the removal of one of these active sites in a murine system treated with prostaglandins it is shown that a response is reflected in Ep levels. Interference of the action of prostaglandins (PG) is altered by the removal of one of these target sites of Ep production. The erythropoietic responses elicited by PGA2, E1, and perhaps the methylated PGE2s act through the liver whereas PGE2 may operate through a renal pathway for its response. PGF reveals no effect on erythropoietic activity and is no different than that observed for vehicle-treated controls. The prostaglandins tested appear to act primarily through the kidney or liver but the possibility exists that some yet undetermined organ site may also be involved.  相似文献   

13.
Previously, tau protein kinase I/glycogen synthase kinase-3/kinase FA(TPKI/GSK-3/FA) was identified as a brain microtubule-associated tau kinase possibly involved in the Alzheimer disease-like phosphorylation of tau. In this report, we find that the TPKI/GSK-3/FA can be stimulated to phosphorylate brain tau up to 8.5 mol of phosphates per mol of protein by heparin, a polyanion compound. Tryptic digestion of32P-labeled tau followed by high-performance liquid chromatography and high-voltage electrophoresis/thin-layer chromatography reveals 12 phosphopeptides. Phosphoamino acid analysis together with sequential manual Edman degradation and peptide sequence analysis further reveals that TPKI/GSK-3//FA after heparin potentiation phosphorylates tau on sites of Ser199, Thr231, Ser235, Ser262, Ser396, and Ser400, which are potential sites abnormally phosphorylated in Alzheimer tau and potent sites responsible for reducing microtubule binding possibly involved in neuronal degeneration. The results provide initial evidence that TPKI/GSK-3/FA after heparin potentiation may represent one of the most potent systems possibly involved in the abnormal phosphorylation of PHF-tau and neuronal degeneration in Alzheimer disease brains.Abbreviations FA the activating factor of type 1 protein phosphatase - GSK-3 glycogen synthase kinase-3 - TPKI tau protein kinase I - SDS-PAGE sodium dodecylsulfate-polyacrylamide gel electrophoresis - PHF paired helical filaments - HPLC high-performance liquid chromatography  相似文献   

14.
Expression of vnd in ventral, ind in intermediate, and msh in dorsal columns of fly neurectoderm, and of homologous gene families in corresponding domains of vertebrate neurectoderm, suggests that elements of dorsoventral neural patterning have been evolutionarily conserved. However, upstream signaling pathways regulating this columnar gene expression pattern appear to have diverged significantly throughout evolution. In addition, while recent loss-of-function studies in flies and mice indicate that these three genes may have a conserved role in regional specification, there is no obvious conservation of the particular cell fates deriving from corresponding domains. The three-column expression pattern may thus represent a developmental mechanism that is more resistant to evolutionary changes than genetic events upstream or downstream of it.  相似文献   

15.
Annual observations of seabirds within Prydz Bay, East Antarctica, between the 1980/1981 and 1992/1993 seasons revealed siginificant changes in abundance of the 9 resident and 15 non-resident species. An estimated 4.85 million individual residents and 2.35 million individual non-residents were present each season. For resident and non-resident species, mean abundance was 3.75 and 1.81 birds/km2, and mean biomass was 6.67 and 1.70 kg/km2, respectively. Based on estimated abundances, the total consumption of marine resources by the seabird community within Prydz Bay ranged from 471,000 to 1.1 million tonnes (mean 752,000±176,000 tonnes) per 6-month summer, or between 2.02 and 4.53 kg/km2 per day (mean 3.23±0.76 kg/km2 per day). The mean energy flux to the seabird community within Prydz Bay each summer was 3.13*1012 kJ, (range: 2.0*1012 kJ–4.4*1012 kJ), of which 66% went to the resident species. Regional abundance and biomass estimates for resident and non-resident species were both negatively correlated; when the estimated abundance and biomass of resident species were high, those of non-resident species were low. Received: 4 January 1996/Accepted: 3 July 1996  相似文献   

16.
Remote limb ischemic preconditioning (RIPC) is a clinically feasible strategy to protect against ischemia/reperfusion injury, but the knowledge concerning the mechanism underlying RIPC is scarce. This study was performed to examine the effect of RIPC on brain tissue suffering from ischemia challenge and explore its underlying mechanism in a rat model. The animals were divided into four groups: Sham, middle cerebral artery occlusion (MCAO), RIPC, and MCAO+RIPC. We found that previous exposure to RIPC significantly attenuated neurological dysfunction and lessened brain edema in MCAO+RIPC group. Moreover, other important events were observed in MCAO+RIPC group, including substantial decrements in the concentrations of oxidative response indicators [malondialdehyde (MDA), 8-hydroxy-2-deoxyguanosine (8-OHdG), and protein carbonyl], significant reductions in levels of inflammation mediators [myeloperoxidase (MPO), tumor necrosis factor-a (TNF-a), interleukin-1β (IL-1β), and IL-6], and significant decline in neuronal apoptosis revealed by a smaller number of TUNEL-positive cells. Interestingly, both MCAO and RIPC groups exhibited meaningful elevations in the levels of HIF-1a, HSP70, and AMP-activated protein kinase (AMPK) compared to Sham group, and previous exposure to RIPC further elevated the levels of HIF-1a, HSP70, and AMPK in MCAO+RIPC group. Furthermore, the administration of YC-1 (HIF-1 inhibitor), 8-bAMP (AMPK inhibitor), and Quercetin (HSP70 inhibitor) to MCAO+RIPC rats demonstrated that HIF-1α/AMPK/HSP70 was involved in RIPC-mediated protection against cerebral ischemia.  相似文献   

17.
为解析黏虫Mythimna separata响应环境胁迫的分子机制,采用RACE和RT-PCR的方法从黏虫中克隆了1个HSP90/70组织蛋白(heat shock 90/70 organizing protein, HOP)基因,并采用qRT-PCR分析了其在多种生物和非生物胁迫下的表达特性。结果表明,MsHOP具有1个1 626 bp的开放阅读框,编码541个氨基酸,预测的分子量为61.7 kDa。序列分析表明,MsHOP主要由已报道的3个保守四肽重复结构域(TPR1, TPR2A和TPR2B)和2个天冬氨酸-脯氨酸重复基序(DP)构成。基于鳞翅目昆虫HOP构建的系统进化树显示MsHOP与棉铃虫Helicoverpa armigera HOP和烟芽夜蛾Heliothis virescens HOP的亲缘关系最近。qRT-PCR分析表明,MsHOP在黏虫所有发育时期和组织均表达,分别在5龄幼虫和雌成虫中肠的表达量最高。在30℃下处理1 h后,MsHOP的表达水平较对照显著提高,而在33℃~39℃下处理1 h后MsHOP的表达水平则与对照差异不显著。饥饿24~72 h后,MsHOP的表...  相似文献   

18.
Comprehensive structural analyses were performed for N-o-, N-m-, and N-p-nitrophenyl-2,3,4-tri-O-acetyl-β-d-xylopyranosylamines. Single-crystal X-ray diffraction data were collected and revealed that one compound under investigation undergoes temperature-dependent polymorph transitions (crystal structures of three polymorphs were obtained). The number of molecules in the independent part of the crystal unit cells was in agreement with the number of resonances in solid-state 13C NMR spectra. Therefore, the compounds exist as single polymorphs at room temperature, as confirmed by powder X-ray diffraction measurements. Significant differences in 13C chemical shifts between solution and solid-state NMR for selected carbon atoms confirmed the existence of intra- and/or intermolecular interactions.  相似文献   

19.
本文旨在运用半定量RT-PCR技术,研究不同浓度及不同时间镉胁迫下,涡虫(Dugesia japonica)体内Dj Hsp70及Dj P53基因的表达规律。提取相同暴露时间(48 h)不同浓度(0,20滋g/L,40滋g/L,80滋g/L,160滋g/L,320滋g/L)及相同暴露浓度(25滋g/L)不同暴露时间(0,1 d,3 d,6 d,9 d,15 d)镉胁迫下涡虫组织总RNA,反转录得到cD NA,以茁-actin作为内参,应用半定量RT-PCR方法,检测Dj Hsp70及Dj P53基因的表达量。结果表明:与对照相比,重金属镉胁迫导致涡虫体内Dj Hsp70、Dj P53基因表达量均上调,存在明显的"毒理兴奋"作用。在25滋g/L镉离子处理15 d后Dj Hsp70基因表达呈现下降趋势。因此,半定量RT-PCR方法应用于淡水生态环境镉污染评价具有较大的潜力。  相似文献   

20.
Summary Breeding ofHippolais polyglotta in the Saarland was first recorded in 1984. In 1985 in a general census study 60 territorial were mapped, 10 nests were found, an 62 individuals could be ringed. Records of old nests indicate that breeding of that species in the Saarland has already started before 1985.  相似文献   

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