Medical diagnostic laboratories have come under further scrutiny to ensure quality standards of their service and external quality assurance (EQA) programs involving multiple laboratories have been ...used to gauge this quality based on a consensus. However, because of the geographical distances within a country or internationally, cell surface marker expressions may change due to time delays and transport temperatures. Attention was given to this issue some decades ago and hence requires a re-evaluation in consideration of updated methods, reagents and instruments for flow cytometry and phenotyping. We have undertaken an extensive study to examine the effects of various conditions on blood storage akin to that experienced by patient samples as well as EQA programs, examining expression of lymphocyte surface markers, CD3, CD4, CD8, CD2, CD19, CD20, CD16/56 and HLA-DR. Assessment of lithium-heparin anticoagulated whole blood showed an increase in percentage of CD3+ and CD8+ T cells and a decrease in CD16/56+ NK cells after storage at room temperature (RT) for 24 and/or 48 h. In comparison, storage at 4°C led to a decrease in percentage of CD4+ and increase in percentage of CD8+ cells. The low temperature also caused an increase in percentage of B cells (CD19+, CD20+). While storage at RT did not alter levels of HLA-DR+ CD3+ T cells, there was a significant increase in percentage of these cells after 48 h. Changes were also seen at both temperatures when EDTA was used as an anti-coagulant. Assessment of blood treated with a stabiliser, normally used in the EQA samples (Streck Cell Preservative), reduced the range of lymphocyte subsets affected, with only CD2+ and CD20+ cells being significantly different at both temperatures, We conclude that 24–48 h storage/transport can affect the percentage of CD3+, CD4+ T cells, CD8+ T cells, B cells, NK cells and HLADR+ T cells which can be minimised by using the blood stabiliser as per EQA programs and we emphasise the need to adopt this in the processing of patients' blood samples.
The various models used in gross anatomical studies to improve the visualization of blood vessels differ in the amount of manual labour, cost, equipment and time involved. This study aimed to compare ...chemical and enzymatic maceration processes for soft‐tissue removal from arterial silicone casts on skull scaffolds using ringed seal (Pusa hispida) skull specimens. Both processes produced specimens that covered all anatomical aspects required to visualize the intracranial arterial arrangement on a bone scaffold. Overall, the enzyme maceration process was better for production of such specimens, as this process is easy and safe to perform, is less harmful to the bony parts of the specimen, and the resulting specimens are visually more appealing for display and teaching. Compared with previously published models, the end result varied in the amount of dissolved bone tissue and the visual presentation of the model.
Recent advances in DNA sequencing technologies have allowed scientists to probe increasingly complex biological systems, including the diversity of bacteria in the environment. However, despite a ...multitude of recent studies incorporating these methods, many questions regarding how environmental samples should be collected and stored still persist. Here, we assess the impact of different soil storage conditions on microbial community composition using Illumina-based 16S rRNA V4 amplicon sequencing. Both storage time and temperature affected bacterial community composition and structure. Frozen samples maintained the highest alpha diversity and differed least in beta diversity, suggesting the utility of cold storage for maintaining consistent communities. Samples stored for intermediate times (three and seven days) had both the highest alpha diversity and the largest differences in overall beta diversity, showing the degree of community change after sample collection. These divergences notwithstanding, differences in neither storage time nor storage temperature substantially altered overall communities relative to more than 500 previously examined soil samples. These results systematically support previous studies and stress the importance of methodological consistency for accurate characterization and comparison of soil microbiological assemblages.
The idea of collecting blood on a paper card and subsequently using the dried blood spots (DBS) for diagnostic purposes originated a century ago. Since then, DBS testing for decades has remained ...predominantly focused on the diagnosis of infectious diseases especially in resource-limited settings or the systematic screening of newborns for inherited metabolic disorders and only recently have a variety of new and innovative DBS applications begun to emerge. For many years, pre-analytical variables were only inappropriately considered in the field of DBS testing and even today, with the exception of newborn screening, the entire pre-analytical phase, which comprises the preparation and processing of DBS for their final analysis has not been standardized. Given this background, a comprehensive step-by-step protocol, which covers al the essential phases, is proposed, i.e., collection of blood; preparation of blood spots; drying of blood spots; storage and transportation of DBS; elution of DBS, and finally analyses of DBS eluates. The effectiveness of this protocol was first evaluated with 1,762 coupled serum/DBS pairs for detecting markers of hepatitis B virus, hepatitis C virus, and human immunodeficiency virus infections on an automated analytical platform. In a second step, the protocol was utilized during a pilot study, which was conducted on active drug users in the German cities of Berlin and Essen.
The stability of urine specimens submitted for culture remains a challenge for many laboratories because of delays in specimen transport. We evaluated the usefulness of BD Vacutainer Plus Urine C&S ...Preservative Tube in ensuring specimen stability.
Clinical urine specimens collected in sterile collection cups (n = 110) were plated onto sheep blood and MacConkey agar following standard laboratory procedures guidelines. Thereafter, specimens were divided into 3 storage conditions: nonpreservative, refrigerated; nonpreservative, room temperature (RT); BD Vacutainer Plus Urine C&S Preservative Tube, RT. For each sample type, additional cultures were set up at 2, 4, 24, and 48 hours.
Initially, 18 specimens had no growth, 32 showed mixed skin flora, and 60 yielded at least 1 uropathogen. Increased colony counts of uropathogens were observed for nonpreserved urine samples stored at RT; these changes were statistically significant. Minor differences between refrigerated urine samples and BD Vacutainer Plus Urine C&S Preservative Tube samples were seen but were not statistically significant.
The use of preservative-containing collection tubes is desirable to ensure specimen stability when prompt processing or refrigeration is not feasible.
Background: Rotavirus is considered worldwide as one of the most important viral gastrointestinal infections, resulting in potentially life-threatening diarrhoea and death in children under the age ...of 5 years. Rotavirus can survive and remain infectious for long periods outside of the human body and can be easily transmitted via environmental surfaces.Method: Stool specimens that had been collected and stored since 2010/2011 at 2°C – 8°C instead of −20°C or −80°C were analysed to determine the viability of rotavirus in these specimens after 6 years of improper storage. The specimens were analysed using simple enzyme immunoassay (EIA) methods from two different suppliers at different times throughout the period (2012–2017).Results: The analysis showed similar detection results for the two EIA kits.Conclusion: The rotavirus can be detected after several years of incorrect storage with EIA kits.
Following an ordered clinical chemistry plasma/serum test, ideally the venous blood specimen is adequately collected at a health care facility, then swiftly transported to and readily handled, ...analyzed and sometimes interpreted at a clinical chemistry laboratory followed by a report of the test result to the ordering physician to finally handle the result. However, often there are practical as well as sample quality reasons for short- or long-term storage of samples before and after analysis. If there are specific storage needs, the preanalytical handling practices are specified in the laboratory’s specimen collection instructions for the ordered test analyte. Biobanking of specimens over a very long time prior to analysis includes an often neglected preanalytical challenge for preserved quality of the blood specimen and also involves administrative and additional practical handling aspects (specified in a standard operating procedure – SOP) when demands and considerations from academic, industry, research organizations and authorities are included. This short review highlights some preanalytical aspects of plasma/serum short- and long- term storage that must be considered by clinicians, laboratory staff as well as the researchers.
A system capable of biocatalytic conversion of distributed sources of single carbon gases such as carbon monoxide into hydrocarbons can be highly beneficial for developing commercially viable ...biotechnology applications in alternative energy. Several anaerobic bacterial strains can be used for such conversion. The anaerobic carbon monoxide-fixing bacteria Clostridium ljungdahlii OTA1 is a model CO assimilating microorganism that currently requires cryogenic temperature for storage of the viable strains. If these organisms can be stabilized and concentrated in thin films in advanced porous materials, it will enable development of high gas fraction, biocomposite absorbers with elevated carbon monoxide (CO) mass transfer rate, that require minimal power input and liquid, and demonstrate elevated substrate consumption rate compared to conventional suspended cell bioreactors. We report development of a technique for dry-stabilization of C. ljungdahlii OTA1 on a paper biocomposite. Bacterial samples coated onto paper were desiccated in the presence of trehalose using convective drying and stored at 4°C. Optimal dryness was ~1g H2O per gram of dry weight (gDW). CO uptake directly following biocomposite rehydration steadily increases over time indicating immediate cellular metabolic recovery. A high-resolution Raman microspectroscopic hyperspectral imaging technique was employed to spatially quantify the residual moisture content. We have demonstrated for the first time that convectively dried and stored C. ljungdahlii strains were stabilized in a desiccated state for over 38 days without a loss in CO absorbing reactivity. The Raman hyperspectral imaging technique described here is a non-invasive characterization tool to support development of dry-stabilization techniques for microorganisms on inexpensive porous support materials. The present study successfully extends and implements the principles of dry-stabilization for preservation of strictly anaerobic bacteria as an alternative to lyophilization or spray drying that could enable centralized biocomposite biocatalyst fabrication and decentralized bioprocessing of CO to liquid fuels or chemicals.
We encountered a patient who received multiple transfusions during treatment for hematologic disease and was found to be infected with hepatitis E virus (HEV). Elevated concentrations of ...hepatobiliary enzyme led to the discovery of HEV infection during outpatient follow-up for Hodgkin's lymphoma. Viral hepatitis-related tests yielded positive results for anti-HEV immunoglobulin A antibody, despite negative results from stored samples collected before transfusion. We reported this case of suspected transfusion-associated HEV infection to the Japanese Red Cross Society. According to a survey by the Japanese Red Cross Society, HEV nucleotide sequences from the patient's post-transfusion specimen were identical to those of the corresponding stored donor specimen, confirming that HEV infection originated from the transfusion. His condition resolved rapidly and did not show a chronic course. While HEV is not included in infectious disease tests for blood donors, the frequency of HEV infection in transfusion recipients has increased in recent years. Indeed, we encountered another transfusion-associated hepatitis E case in the same period at our hospital. Our findings from these two cases suggest that medical institutions in the Hokkaido area, as well as the Kanto-Kohshinetsu area should be on alert regarding the high prevalence of HEV. Our findings also highlight the importance of pre-transfusion storage of patient specimens.
Volume is a proxy for biomass in hard-bodied arthropods. We constructed a highly significant overall equation relating biomass and volume for Neotropical dung beetles (Scarabaeidae). In addition, we ...constructed separate equations for 12 Neotropical genera of scarabs, of which 11 were highly significant. In general, linear functions explained the relationship between biomass and volume equally well as log-transformed data. In addition, we tested the effects of alcohol storage on volume over the course of a year and found no significant change in dung beetle volume. Because scarab volume is not affected by alcohol storage up to a period of 1 yr, the biomass–volume equations we have provided for fresh specimens may be valid to quantify biomass of specimens stored in alcohol.
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