某天然植物性洗洁精的毒性研究

目的 对某天然植物性洗洁精进行毒性研究。方法 按GBl5193-1994《食品安全性毒理学评价程序和方法》进行。结果 本品经口LD50g／kg，属无毒级：未见有致突变作用；30d喂养试验显示对动物体重、血常规及肝、肾功能等无明显影响；病理学检查结果显示对肾、睾丸组织细胞有轻度毒性作用。结论 该天然植物性洗洁精是一种基本无毒的产品，但对肾、睾丸组织的损害作用有待作进一步的毒性研究。     

Glycoproteins of representative paramyxoviruses: isolation and antigenic analysis using a zwitterionic surfactant.

A new method for the isolation of biologically active envelope antigens from paramyxo- and myxoviruses was developed using a zwitterionic detergent Empigen BB. Essentially complete recovery of hemagglutinin and sialidase from representative paramyxoviruses (PMY, NDV, and Sendai virus) and influenza virus X7 was achieved. The glycoproteins (HN and F) of PMY were purified in a DEAE-Bio-Gel A column equilibrated with bicarbonate buffer containing Empigen, Polyacrylamide gel electrophoresis analysis of pooled HN fractions revealed one band, indicating that it is a common glycoprotein. Gels of pooled F-enriched fractions revealed three bands corresponding to LGP, HN, and F. Gels of PMY virus revealed six polypeptides, and they have been tentatively designated L, LGP, HN, F, NP, and M. LGP, a large glycoprotein, was not detected in gels of NDV and Sendai virus. It has been proposed that LGP may consist of a complex of F. Antiserum was prepared against purified HN and it was found to be monospecific. The antiserum inhibited both hemagglutination and enzyme activities of PMY, which is in support of the hemagglutinin and sialidase of PMY being associated with a common glycoprotein. By enzyme inhibition analysis of PMY, NDV, and Sendai virus, it was shown that the enzymes of these viruses are antigenically distinct. The methods described for the isolation and purification of PMY glycoproteins may be useful for the preparation of myxo- and paramyxovirus subunit vaccines.     

Lanolin of reduced sensitizing potential

Confirmation has been obtained that reducing the content of natural free alcohols in lanolin to below 3 % particularly in the absence of detergent residues, reduces the incidence of positive patch test reactions amongst selected lanolin-sensitive skin patients by 99.3 %. Only one reaction out of 149 subjects was recorded.     

Modified salting-out method: high-yield, high-quality genomic DNA extraction from whole blood using laundry detergent

Different approaches have been used to extract DNA from whole blood. In most of these methods enzymes (such as proteinase K and RNAse A) or toxic organic solvents (such as phenol or guanidine isothiocyanate) are used. Since these enzymes are expensive, and most of the materials that are used routinely are toxic, it is desirable to apply an efficient DNA extraction procedure that does not require the use of such materials. In this study, genomic DNA was extracted by the salting-out method, but instead of using an analytical-grade enzyme and chemical detergents, as normally used for DNA isolation, a common laundry powder was used. Different concentrations of the powder were tested, and proteins were precipitated by NaCl-saturated distilled water. Finally, DNA precipitation was performed with the use of 96% ethanol. From the results, we conclude that the optimum concentration of laundry powder for the highest yield and purity of isolated DNA is 30 mg/mL. The procedure was optimized, and a final protocol is suggested. Following the same protocol, DNA was extracted from 100 blood samples, and their amounts were found to be >50 microg/mL of whole blood. The integrity of the DNA fragments was confirmed by agarose gel electrophoresis. Furthermore, the extracted DNA was used as a template for PCR reaction. The results obtained from PCR showed that the final solutions of extracted DNA did not contain any inhibitory material for the enzyme used in the PCR reaction, and indicated that the isolated DNA was of good quality. These results show that this method is simple, fast, safe, and cost-effective, and can be used in medical laboratories and research centers.     

内分泌干扰物对精液质量的影响

内分泌干扰化合物(endocrine disrupting chemicals,EDCs)是指外源性的能干扰人类或动物内分泌系统诸环节并导致异常效应,或使其后代内分泌功能发生改变的化学物质。EDCs种类繁多,广泛存在于土壤、水、甚至食物中。本文从农药、塑料增塑剂和洗涤剂这3类常见EDCs着手,从流行病学和生物学角度阐述了其对人类及动物精液质量的影响。     

Study on the Preparation of Decellularized Scaffold of Bovine Pericardium

Objective: To search for the best procedure on preparation of acellular bovine pericardium,so to provide scaffolds for constructing tissue-engineering Methods:The bovine pericardiums were treated with 5 methods,which were divided into 6 groups.Group A:Fresh bovinepericardium;GroupB:Trypsin-detergentgroup;GroupC:Freeze-thaw-detergent24 h group;Group D:.Freeze-thaw-detergent 48 h group;Group E:Freeze-thaw-nuclease group;Group F:Detergent-nuclease group.Then,by HE staining and scanning electron microscope to observe the effects of decellularization and fibrous changes among the 6 groups;by water content testingmechanical testing to observe the changes in physical properties of the matrix;by detecting the DNA content of each group to determine the effect of decellularization qualitatively;by cytotoxicity test to detect the biocompatibility of bovine pericardium in each group.Results:The 5 methods can all remove the cellular components effectively,compared with the fresh bovine pericardium,the water content of each decellularized group were increased (P＜0.05),while the DNA content decreased (P＜0.05),with statistically significant differences.Of group E,the fibers were a little disorder,with the largest tension and the elastic modulus increased,while the rupture tensile rate decreased.Compared with fresh bovine pericardium,the largest tension of the other decellularization groups were all decreased (P＜0.05).The fibers of group B,group D were irregularly arranged and also with ruptures,both the elastic modulus and the rupture tensile rate decreased(P＜0.05).In group C and F,the fibers were dense and their direction was normal,the elastic modulus and the rupture tensile rate were similar to the fresh bovine pericardium (P＞0.05).Cytotoxicity results showed that the cell toxicity of group B,group C,group D,group E and group F were respectively 0.9,0.6,1.0,1.0 and 0.5,each group were qualified toxicity test,in which group C and group F were with the lowest cytotoxicity.Conclusion:Group C and group F can remove the cell components of bovine pericardium successfully,while maintaining the major structural components and the histological and biological properties of bovine pericardium,and with low cytotoxicity.However,group C is more economical than group F,and easier to operate.So the method on freeze-thaw-detergent 24 h can be the best choice to produce a decellularized bovine pericardium.     

The Influence of Circulatory and Gut Luminal Challenges on Bidirectional Intestinal Barrier Permeability in Rats

Background: The endothelial and epithelial barriers are important for maintenance of intestinal barrier function. The present study evaluated the response of these barriers after various challenges. Methods: Mucosal endothelial and epithelial barrier integrity was evaluated by the leakage of human serum albumin, labeled with different isotopes, from the circulation to the interstitium and the intestinal lumen, or from the intestinal lumen to the interstitium and the circulation, in rats with endothelial or epithelial challenge. Results: Epithelial barrier dysfunction and alterations in epithelial microvillous ultrastructure showed a pattern dependent on the dose of the intraluminal detergents, whereas only higher doses induced an increase in endothelial barrier permeability. Intravenous challenge with CHAPS or Triton caused a dose-dependent increase in both endothelial and epithelial barrier permeability. The development of endothelial barrier dysfunction was related to a decrease in blood pH values. Conclusions: The results indicate that capillary endothelial barrier integrity may play an important role in maintaining intestinal barrier function and that endothelial injury may initiate or at least be involved in the development of intestinal barrier failure.     

A chromatographically purified human TGF-β1 fraction from virally inactivated platelet lysates

Background and Objectives TGF‐β1 exerts important physiological functions in osteogenesis and chondrogenesis and may be of therapeutic interest. The aim of this work was to develop a scalable purification process of TGF‐β1 from virally inactivated human platelets. Study Design and Methods Apheresis platelet concentrates (N = 12) were solvent/detergent (S/D) treated (1% TnBP/1% Triton X‐45; 31 °C) and the resulting platelet lysates were clarified by oil extraction and centrifugation, then chromatographed on an anion‐exchange DEAE‐Sepharose Fast‐Flow column equilibrated in a PBS buffer, pH 7·5. The column was washed to eliminate unbound proteins and the S/D agents. Bound proteins were eluted using a 1 M NaCl–PBS buffer pH 7·5 (DEAE‐eluate). The content in TGF‐β1, PDGF‐AB, VEGF, IGF‐1, EGF, and b‐FGF was measured by ELISA. Proteins, lipids, and S/D agents were assessed. Protein profile was determined by SDS‐PAGE under reduced or non‐reduced conditions. Results Most proteins, including albumin and immunoglobulins G, A, and M did not bind to the DEAE column as evidenced also by SDS‐PAGE. Essentially all PDGF, VEGF, and IGF were in the breakthrough. The DEAE‐eluate contained close to 60% of the TGF‐β1 at a mean concentration of about 102 ng/ml, whereas EGF, b‐FGF were at about 0·72 and 0·18 ng/ml, respectively. The content in TnBP and Triton X‐45 was <2 ppm. Conclusion A fraction enriched in TGF‐β1 can be prepared from virally inactivated human platelet lysates using an easily scale process. Its interest in regenerative medicine and cell therapy will be evaluated in further studies.