Simple and inexpensive long-term preservation methods for Phytophthora infestans.

Phytophthora infestans is one of the most notorious pathogen among Phytophthora species causing potato late blight disease. Stable and long-term preservation of this pathogen is essential for biological research and fungicide screening. The aim of this study was to find a suitable long-term preservation method for P. infestans. We adjusted the storage temperature, made a slight modification to the rye seed method, and compared the influence of four preservation methods (the mineral oil method, the sterile water method, the rye seed method, and the modified rye seed method) on survival, growth and virulence of four isolates of P. infestans. The results showed that all four methods maintained high viability of the tested P. infestans isolates, but the two rye seed methods were the best ways to maintain 100% viability of the P. infestans isolates without contamination. The four preservation methods did not significantly influence growth or morphological characteristics of the P. infestans isolates. The impacts of the four methods on the virulence of the four P. infestans isolates were isolate-specific. For isolates YF3 and 64093, all four methods were suitable for maintaining their virulence. Whilst for isolate HQK8-3, the rye seed and sterile water methods were more suitable to maintain its virulence than the other two methods. For isolate 32835, storage under mineral oil was the best method for maintaining its virulence. In view of these results, it is recommended P. infestans should be stored by several different storage methods to ensure the safety and stability of the isolates.

A pharmacoeconomic analysis of the collection and preservation of samples in the biobank of the "Instituto Nacional de Cancerología" in Mexico City.

In this work we estimated the budgetary impact of the samples produced by the biobank of the "Instituto Nacional de Cancerología" (BT-INCan) to set a recuperation fee from the perspective of the Health Ministry of Mexico. The study is an observational retrospective review of the direct medical costs (DMCs) of the processes involved in cryopreservation of the samples collected, on a per sample basis, including materials, laboratory tests, personnel, and administrative costs. Materials and labor costs were determined by information collected from the BT-INCan. DMCs were provided depending on the type of sample: plasma, tissue and biopsy; they were calculated according to the process required to preserve them. Sensitivity analysis was performed using bootstrap. Recuperation costs ranged from 130 to 155 USD. Costs were considered on a 5-year time frame for the maintenance per sample, which is the average time that a sample is kept in the BT-INCan. The cost analysis is perceived as an approximation to the most adequate recuperation fee per sample needed to guarantee the correct development of the BT-INCan. This work provides a basis and valuable information about costs, to enable several health institutions to strategically plan and manage a biobank or even motivate to establish their own biobank.

Economic, human and environmental health benefits of replacing formaldehyde in the preservation of corpses.

Formaldehyde has been prominent in preserving biological tissues since the nineteenth century. Despite being admittedly harmful to health and to the environment, it is still widely used. The Morphology Department of the University of Brasília - Brazil, applied the rethink, reduce, reuse, recycle and responsibility methodology to their activities in an effort to protect the health of laboratory workers and users, save resources and reduce damage to the environment. Here we evaluate the results obtained a decade after the implementation of this proposal (2005-2015). Formaldehyde was replaced by alcohol and glycerol solutions in corpse conservation. Over five thousand dollars in public funds that would have been destined to buying preserving substances were saved annually, and over a hundred thousand liters of water that would have been contaminated and thrown into the sewage system were spared. The environment used to implement the study was improved and anatomical parts kept for study had their lifespan extended. It is noteworthy that such simple adjustments could cause pronounced changes in laboratory activities. We would avoid contaminating billions of liters of water and it would be possible to save millions if similar practices were implemented in all educational institutions having similar routines.

Preservation of continuous cell lines at -85°C: a low-cost alternative for resource limited countries.

BACKGROUND: Cell culture is the most popular method of virus propagation because of its high sensitivity. However, the need of high cost liquid nitrogen for storage of cell lines is one of the main limiting factor for its widespread use in developing countries. OBJECTIVE: The present study was therefore carried out to standardize the preservation of continuous cell lines at deep freezer (-85ºC) for 6 months. METHODS: Fixed number of Vero and Hep2 cells were preserved at -85ºC deep freezer in separate vials and were revived at one month interval to check the growth pattern. RESULTS: Both the cell lines could be revived with healthy cells and monolayer was formed within 7-10 days, after storage at -85ºC for 4 months. CONCLUSION: The present study highlights the utility of -85ºC deep freezer as an alternative to liquid N 2 for preservation of these cell lines at least up to four months.

Compositional changes in sugarcane bagasse on low temperature, long-term diluted ammonia treatment.

Sugarcane bagasse is the major by-product of the sugar industry. It has a great potential for the production of biofuels and chemicals due to its considerable amount of cellulose and hemicellulose. In this study, we investigated a simple and economic pretreatment process using dilute ammonia for the storage of sugarcane bagasse. Sugarcane bagasse was stored in 0, 0.03, and 0.3% (w/w) ammonium hydroxide in a closed bottle for 40 days at 30 degrees C under atmospheric pressure without any agitation or circulation. Samples were taken every 10 days and analyzed for changes on lignin, cellulose, hemicellulose composition, ammonia concentration, and microbial counts. Biomass storage for 40 days at 0.3% ammonium hydroxide removed 46% of lignin and retained 100% cellulose and 73% hemicellulose.

[Prescreening of the activity of alanine aminotransferase enhances the cost-effectiveness of blood storage].

The cost-effectiveness of prescreening for alanine aminotransferase (ALT) activity was evaluated in blood donors before donation. Since September 15, 2006, the Krasnodar Territory blood transfusion station has examined more than 32 thousand donors in this fashion. A Reflotron Plus biochemical analyzer (Roche Diagnostics, Switzerland) was used. In 2008, 1230 subjects with increased ALT activity were withdrawn from donation. A total of 17,096 persons were examined. Their examination cost 1,219,457.8 rubles. Non-productive outlays of 7,773,919.8 rubles were prevented. The savings amounted to 6,554,462.12 rubles. Prescreening for ALT was found to be cost-effective if the rate of positive results in the donor population was 1.13% or more.

Um estudo sobre valoraçäo da biodiversidade / A study about value to the price for the preservation of biodiversity

Relata que a conservaçäo da biodiversidade aparece entre as principais questöes ligadas à economia do meio ambiente. Observa que, se a biodiversidade näo pode ser medida, näo há como formar decisöes racionais no que se refere à preservaçäo das espécies, pois a análise de medidas que visem à conservaçäo ecológica fica prejudicada na medida em que cada qual carrega consigo ganhos esperados e perdas imediatas de bem-estar para sociedade. Tem por objetivo apresentar uma metodologia que permite impor preço à proteçäo da biodiversidade. Tenta estabelecer um intervalo de confiança para o valor que a sociedade estaria disposta a pagar, por meio de um imposto do tipo "lump sum", para execuçäo de um programa de preservaçäo de algumas espécies. Enfatiza que a viabilidae, ou probabilidade de que a espécie näo seja extinta no futuro, o grau de diversidade genético e o seu valor de uso säo alguns dos fatores que intervêm na formaçäo do preço da preservaçäo da espécie.

Comparison of different culture media and storage temperatures for the long-term preservation of Streptococcus pneumoniae in the tropics.

OBJECTIVE: The preservation of Streptococcus pneumoniae by standard freezing methods for subsequent tests--such as serotyping and antibiotic susceptibility--is not possible or is difficult in many developing countries because of the high cost of equipment, inadequate equipment maintenance, and irregular power supply. We evaluated alternative low-cost methods, by comparing different culture media and storage temperatures. METHODS: Clinical isolates of five capsular types (1, 5, 7, 19, and 23) of S. pneumoniae were preserved in rabbit blood, sheep blood, skimmed milk, or glycerol-chocolate broth, and stored at -20 degrees C or -70 degrees C. The cultures were also preserved by lyophilization or sand desiccation, followed by storage at room temperature and 4 degrees C. The viability of the preserved cultures was determined by making serial colony counts on day 0 and after 1 week, 4 weeks, 4 months and 16 months. The viability of cultures preserved by sand desiccation and storage at 4 degrees C was also determined every 6 months for up to 68 months. FINDINGS: Irrespective of the media used, cultures maintained at -20 degrees C became nonviable by the fourth month, while those maintained at -70 degrees C were still viable at 16 months. Cultures preserved by lyophilization or sand desiccation lost their viability by the fourth month when maintained at local room temperature (30-42 degrees C), but remained viable when stored at 4 degrees C for up to 68 months. CONCLUSIONS: Our results confirm that freezing at -70 degrees C, or lyophilization and storage at 4 degrees C are the ideal methods for the preservation of S. pneumoniae. In laboratories where lyophilization is not feasible, sand desiccation and storage at 4 degrees C offers an alternative low-cost method for the long-term preservation of S. pneumoniae.

[Cost analysis of a bone bank]. / Kostenanalyse einer Knochenbank.

The costs of a bone-bank working in accordance with the guidelines of the german federal chamber of physicians are described. Establishing a bone-bank storing deep-frozen bone is not very expensive. The main costs are due to laboratory costs for excluding HIV, hepatitis, syphilis and bacterial contamination of bone grafts. In our experience with 206 bone grafts about 20% of them are to be discharged because of positive laboratory tests. The costs of each bone graft are DM 327. A second HIV-Test of the donor 3 months after explantation of a bone graft will cause rising of costs up to 47%. About 20-30% of bone graft donors will probably not carry out this test. In this case discharging of the bone graft is necessary.