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1.
We encountered a patient with heavy Hymenolepis nana infection. The patient was a 44-year-old Korean man who had suffered from chronic hepatitis (type B) for 15 years. A large number of H. nana adult worms were found during colonoscopy that was performed as a part of routine health screening. The parasites were scattered throughout the colon, as well as in the terminal ileum, although the patient was immunocompetent. Based on this study, colonoscopy may be helpful for diagnosis of asymptomatic H. nana infections.  相似文献   
2.
This work describes a quick semi-quantitative colony immunoassay (QSCI) method for immunoblot detection of intracellularly expressed proteins in both yeast and bacterial cells. After induction of protein expression, only 4.5 h is required for cell breakage, protein detection, and data analysis. This protocol was used to screen and unambiguously identify Saccharomyces cerevisiae cells efficiently overexpressing glutathione S-transferase (GST)-tagged Yih1 in addition to cells expressing the myc-tagged large 297-kDa Gcn1 protein. In addition, the method was used to identify Escherichia coli cells efficiently expressing His6-tagged Yih1 and a GST-tagged Gcn1 fragment, respectively. The protocol allows the use of both epitope-specific and protein-specific antibodies. The same colony immunoassay can also be used to determine the minimal concentration of inducing agent sufficient for induction of optimal protein expression (e.g., galactose for yeast, isopropyl β-d-1-thiogalactopyranoside [IPTG] for E. coli). To our knowledge, this is the first report on a rapid low-cost procedure that allows the calibration of inducing agent on solid medium.  相似文献   
3.
一株高效四环素降解菌的分离鉴定及其降解性能研究   总被引:1,自引:0,他引:1  
四环素类抗生素在畜牧养殖业中广泛使用,但其结构复杂,难降解,容易在水环境中积蓄,进而对生态环境产生深远影响,许多国家已将抗生素污染列为重要的环境问题展开了相关的基础研究。近年来利用微生物降解环境中的抗生素污染物成为研究热点。采用选择性培养基,从某制药厂排污口的水样中分离筛选到1株具有较高降解四环素能力的菌株4002,经形态观察、生理生化测定和16S r DNA序列分析,将该菌初步鉴定为Advenella sp.。从p H、溶氧量、无机盐等方面对菌株降解四环素的性能进行研究。结果表明,该菌株降解四环素的适宜p H为7.0,在有氧条件下,30℃,150 r/min振荡培养6 d,可使初始浓度为50μg/m L四环素降解率达57.8%。无机盐对降解率有显著影响,添加Fe SO4和Mn SO4对四环素降解有促进作用,Mg SO4影响不大,Ca SO4则有抑制作用。在培养至第8天时,培养液经HPLC检测显示6.022 min处出现新的吸收峰,推测为降解产物。  相似文献   
4.
Autophagy is an important catabolic program to respond to a variety of cellular stresses by forming a double membrane vesicle, autophagosome. Autophagy plays key roles in various cellular functions. Accordingly, dysregulation of autophagy is closely associated with diseases such as diabetes, neurodegenerative diseases, cardiomyopathy, and cancer. In this sense, autophagy is emerging as an important therapeutic target for disease control. Among the autophagy machineries, PIK3C3/VPS34 complex functions as an autophagy-triggering kinase to recruit the subsequent autophagy protein machineries on the phagophore membrane. Accumulating evidence showing that inhibition of PIK3C3/VPS34 complex successfully inhibits autophagy makes the complex an attractive target for developing autophagy inhibitors. However, one concern about PIK3C3/VPS34 complex is that many different PIK3C3/VPS34 complexes have distinct cellular functions. In this study, we have developed an in vitro PIK3C3/VPS34 complex monitoring assay for autophagy inhibitor screening in a high-throughput assay format instead of targeting the catalytic activity of the PIK3C3/VPS34 complex, which shuts down all PIK3C3/VPS34 complexes. We performed in vitro reconstitution of an essential autophagy-promoting PIK3C3/VPS34 complex, Vps34–Beclin1–ATG14L complex, in a microwell plate (96-well format) and successfully monitored the complex formation in many different conditions. This PIK3C3/VPS34 complex protein assay would provide a reliable tool for the screening of autophagy-specific inhibitors.  相似文献   
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Parkinson's disease (PD) is a movement disorder caused by the progressive loss of dopaminergic neurons. Natural antioxidants and plant extracts with neuroprotective properties offer a promising new therapeutic approach for PD patients, but a suitable large‐scale screening system is required for their discovery and preclinical analysis. Here we used the red flour beetle (Tribolium castaneum ) as a whole‐animal screening system for the detection and characterization of neuroprotective substances. Paraquat was added to the diet of adult beetles to induce PD‐like symptoms, which were quantified using a novel positive geotaxis behavioral assay. These paraquat‐induced behavioral changes were reduced in beetles fed on diets supplemented with l‐ dihydroxyphenylalanine, ascorbic acid, curcumin, hempseed flour, or the Chinese herb gou‐teng. T. castaneum is, therefore, a valuable model for the screening of neuroprotective substances in chemical libraries and plant extracts and could be developed as a model for the preclinical testing of therapeutic candidates for the treatment of neurodegenerative diseases, such as PD.  相似文献   
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Purpose: Identification of biomarkers in major depressive disorder (MDD) has proceeded in an extemporised manner. No single biomarker has been identified with utility in screening, diagnosis, prognosis, or monitoring, and screening tests have different characteristics than the other functions. Using chaos, bifurcation, and perturbation (CBP) theories, the aim is to identify biomarkers to aid clinicians in screening for MDD.

Materials and methods: MDD is a complex disorder; consequently, a reductionist approach to characterize the complex system changes found in MDD will be inchoate and unreliable. A holistic approach is used to identify biomarkers reflecting the tipping points seen before the catastrophic bifurcation that results in MDD.

Results: Applying CBP theories revealed skew, resistance to change, flickering, increased variance and autocorrelation as patterns of biomarkers. Integrals and differentials of extracellular and intracellular biomarkers were identified, specifically focussed on hypothalamo-pituitary axis (HPA) dysfunction, metabolic dysfunction, inflammation and mitochondrial oxidative stress, and tryptophan metabolism.

Conclusions: Applying CBP theories to the dysfunctional complex biological systems in MDD led to development of integrals and differentials of biomarkers that can be used in screening for MDD and planning future biomarker research, targeting intracellular and extracellular inflammation, HPA axis dysfunction, and tryptophan metabolism.  相似文献   

10.
溶磷性大豆根瘤内生菌的筛选、抗性及系统发育和促生   总被引:4,自引:0,他引:4  
对采自河南省不同地区的大豆根瘤进行内生菌分离纯化、溶磷性筛选试验。根据能否产生溶磷圈及溶磷圈直径(D)、菌落直径(d)和D/d值大小确定菌株溶磷能力,采用钼锑抗比色法测定培养液中有效磷含量;平板筛选法对筛选菌株进行耐盐性、耐酸碱、重金属等抗性测定,并对筛选菌株进行理化特性、16S r DNA、rec A序列和系统发育分析。结果表明,从分离纯化的324株内生菌中筛选出36株具有溶磷特性,其中20株有较强溶磷性。菌株DD291发酵液中可溶性磷含量最高(452 mg/L),发酵液p H与对照相比均有不同程度下降,最大降幅达2.92。大部分溶磷性内生菌具有较强耐盐碱性,对Pb2+、Cr6+和Cu2+有较高耐受性,对Ni2+和Hg2+抗性较弱。结合细胞形态、生理生化、16S r DNA、rec A序列和系统发育分析结果,菌株确定为Bacillus cereus,Enterobacter cancerogenus,E.cloacae和Pseudomonas putida。部分溶磷菌株对大豆的生长有促进作用,显示出潜在的应用前景。  相似文献   
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