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561.
On Day 5 after immunization with Trypanosoma gambiense, spleens were removed from immune mice. Spleen cell suspensions were passed through a glass bead column and separated into filtrate and adherent cell subpopulations. Each subpopulation was transferred into normal mice intraperitoneally, and the production of agglutinins and the protection against experimental infection with T. gambiense were studied in vivo. The adherent subpopulation contained cells which were capable of producing and releasing the agglutinin into the serum of the recipient, but the filtrate did not contain such cells.The adherent fraction was found to be effective in the prevention of experimental infection, but the filtrate was only slightly effective. When both cell subpopulations were mixed together, immune responses were enhanced. With cortisone and anti-mouse thymic cell serum treatment before immunization with trypanosomal antigen, agglutinin production was greatly suppressed, and the mice were not protected against experimental infection. However, after treatment of immune spleen cells in vitro with anti-mouse thymic cell serum, recipients of viable cells showed agglutinin production and were found to withstand infection.  相似文献   
562.
MicroRNA-567 (miR-567) plays a decisive role in cancers whereas its role in non-small cell lung cancer (NSCLC) is still unexplored. This study was therefore planned to explore the regulatory function of miR-567 in A549 NSCLC cells and investigate its possible molecular mechanism that may help in NSCLC treatment. In the current study, miR-567 expression was examined by quantitative real time-polymerase chain reaction (qRT-PCR) in different NSCLC cell lines in addition to normal cell line. A549 NSCLC cells were transfected by miR-567 mimic, miR-567 inhibitor, and negative control siRNA. Cell proliferation was evaluated by MTT and 5-bromo-2′deoxyuridine assays. Cell cycle distribution and apoptosis were studied by flow cytometry. Bioinformatics analysis programs were used to expect the putative target of miR-567. The expression of cyclin-dependent kinase 8 (CDK8) gene at mRNA and protein levels were evaluated by using qRT-PCR and western blotting. Our results found that miR-567 expressions decreased in all the studied NSCLC cells as compared to the normal cell line. A549 cell proliferation was suppressed by miR-567 upregulation while cell apoptosis was promoted. Also, miR-567 upregulation induced cell cycle arrest at sub-G1 and S phases. CDK8 was expected as a target gene of miR-567. MiR-567 upregulation decreased CDK8 mRNA and protein expression while the downregulation of miR-567 increased CDK8 gene expression. These findings revealed that miR-567 may be a tumor suppressor in A549 NSCLC cells through regulating CDK8 gene expression and may serve as a novel therapeutic target for NSCLC treatment.  相似文献   
563.
Captive breeding is often touted as a way to preserve species disappearing in the wild. Zoos and related institutions have limited space for animals, however, and use of what space exists may be restricted by conflicting demands of entertainment, education, and propagation. Curators of US bird collections sponsored an analysis of space available for long-term captive management. Seventy-three collections responded to a survey, providing data on 3,174 exhibits and holding areas under their control. The most optimistic analysis indicates room for fewer than 141 long-term management programs. To use space resources optimally for conservation, there is a strong need to develop priorities within management groups. New models and strategies for using captive propagation as a short-term tool to bolster wild populations should be created. Immediate attention should be paid to the most effective and efficient ways of improving husbandry and management techniques for birds. © 1995 Wiley-Liss, Inc.  相似文献   
564.
Most fungal biology researchers depend on culture collections, or more aptly, ex situ fungal germplasm repositories, either for the materials upon which they work, or as a long-term home for their materials after their projects are finished. These collections are broadly distributed and typically supported by the local government. The large number of collections, notwithstanding, some collections have greater impact than others. This review will discuss the fungal germplasm repositories around the world with special attention paid to the Fungal Genetics Stock Center. To facilitate their activities collections have joined together in networks, both locally and internationally. Additional information on public policy and how it impacts collections will be presented and the impact of collections will be highlighted.  相似文献   
565.
《Cell host & microbe》2022,30(1):124-138.e8
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566.
In recent years, the remarkable spread of Aedes albopictus (Skuse) (Diptera: Culicidae) throughout the world has drawn attention to this hitherto poorly studied species, particularly after its role in outbreaks of chikungunya fever in the western Indian Ocean and in Italy. Variants of sterile insect technique (SIT), including the release of transgenic males with a dominant lethal gene (RIDL), have been proposed in the search for new and innovative methods of control. Knowledge of male dispersal, mating behaviour and longevity will be critical to the success of this approach. We present an effective and practical method for trapping both male and female Ae. albopictus using a mouse-baited BG-Sentinel trap.  相似文献   
567.
Jill D. Mellen 《Zoo biology》1994,13(5):459-470
In addition to genetic and demographic considerations, SSP coordinators have been asked to systematically address husbandry issues. Three approaches to the study of captive management issues are typically used: (1) large numbers of individuals are housed at a single institution maintained in a situation that facilitates systematic evaluation of the captive environment, (2) an investigator travels to many institutions to gather data on a single taxon, or (3) an investigator surveys existing information by assembling data from a large number of individuals at a variety of institutions. Each approach has both advantages and disadvantages in terms of feasibility and the type of results obtained. The use of surveys to obtain information about husbandry parameters from a large number of animals maintained at a variety of zoos is quite possibly the most common approach used among zoo managers. Zoo husbandry surveys are typically developed to address issues problematic to a particular species, including reproductive failure and health issues. Unfortunately, surveys appear to be an often misused research tool among zoo professionals. Surveys can be improved by working with psychologists or sociologists at local universities, by narrowing the focus of the survey's purpose, and by carefully constructing each question. © 1994 Wiley-Liss, Inc.  相似文献   
568.
Recently, we reported high antibacterial efficiency of Loranthus acaciae (LA) against different standard strains of bacteria including Methicillin-Resistant Staphylococcus aureus (MRSA). Therefore, this study aimed to confirm the effectiveness of LA against clinically isolated Staphylococcus aureus (SA) including β-lactamase producer (Blac) and MRSA. Forty-eight SA isolates collected from various clinical samples were used in this study. Antibiotics susceptibility profile was determined for twenty different antibiotics using automated Microscan Walkaway 96 Plus system as recommended by Clinical and Laboratory Standards Institute (CLSI) guidelines. This system also identified β-lactamase producers and MRSA. In the meantime, LA ethanolic extract was fractionated using liquid–liquid fraction method to hexane, dichloromethane DCM and methanol 80% fractions. Antimicrobial activities of LA extract and fraction were performed with agar well diffusion method for all SA isolates, MIC and MBC were also recorded. Phytochemical screening for various phyto-constituent classes of LA ethanolic extract was determined. Out of 48 SA isolates, Cefoxitin-positive MRSA represent 31 (64.6%), Blac 17 (35.4%), and 41 (85.4%) were multidrug-resistant SA, which was resistant at least to one antibiotic from three different categories. All isolates were resistant to ampicillin and penicillin. Antimicrobial activities of LA extract and fractions revealed that ethanol extract was active against all isolated SA with inhibition zone ranged from 33 ± 2.00 to 25 ± 3.05 mm. While DCM exhibited the largest inhibition zone range from 37 ± 3.00 to 33 ± 2.00 mm. This study is first of its kind conforming the high antibacterial activity of LA against SA isolated from a different source of infection. The study concluded that LA extract and fractions are active and give positive result for all isolated SA. Therefore, suitable pharmacological formulation of LA extract as a promising antibacterial agent for the treatment of SA infection should be given extreme priority.  相似文献   
569.
570.
Summary One of the major problems in cell culturing is the misidentification or cross-contamination of authentic continuous cell lines. We applied a rapid and efficient isoelectric focusing (IEF) technique for the routine analysis to detect interspecies contamination of cell cultures and for the identification of unknown animal cell lines. The method is based on the isoelectric separation of a specific set of intracellular enzymes which can be used to distinguish between cell lines of human, murine, or other mammalian origin. By means of preformed agarose gels, standardized conditions and equipment, this technique is especially applicable for routine work and allows the analysis of a large number of unknown samples with reproducible results. One hundred seventy-seven cell lines which have been sent to the Department of Human and Animal Cell Cultures at the DSM (Deutsche Sammlung von Mikroorganismen and Zellkulturen) were analyzed for species authentication; only three cell lines were found not to be of the presumed species. Our study strongly emphasizes standardized IEF as an efficient and rapid method for routinely monitoring the authenticity of cell lines.  相似文献   
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