OBJECTIVES: The purpose of this study was to evaluate in vitro cytotoxicity of the pozzolan cement and other root-end filling materials using human periodontal ligament cell. MATERIALS AND METHODS: Endocem (Maruchi), white ProRoot MTA (Dentsply), white Angelus MTA (Angelus), and Super EBA (Bosworth Co.) were tested after set completely in an incubator at 37degrees C for 7 days, Endocem was tested in two ways: 1) immediately after mixing (fresh specimens) and 2) after setting completely like other experimental materials. The methods for assessment included light microscopic examination, cell counting and WST-1 assay on human periodontal ligament cell. RESULTS: In the results of microscopic examination and cell counting, Super EBA showed significantly lower viable cell than any other groups (p < 0.05). As the results of WST-1 assay, compared with untreated control group, there was no significant cell viability of the Endocem group. However, the fresh mixed Endocem group had significantly less cell viability. The cells exposed to ProRoot MTA and Angelus MTA showed the highest viability, whereas the cells exposed to Super EBA displayed the lowest viability (p < 0.05). CONCLUSIONS: The cytotoxicity of the pozzolan cement (Endocem) was comparable with ProRoot MTA and Angelus MTA. Considering the difficult manipulation and long setting time of ProRoot MTA and Angelus MTA, Endocem can be used as the alternative of retrofilling material.
Cell Count ; Cell Survival ; Humans* ; Incubators ; Methods ; Periodontal Ligament* ; Pemetrexed

This study was aimed to explore the effect of different cryopreservation time on recovery rate of cord blood stem cells, and analyze the influence of cord blood cells after thawing on the engraftment speed of cord blood cells in patients. 20 cord blood units were stored at -196°C for 1 - 10 years. The cell viability, content of total nucleated cell (TNC), CD34(+) cells and the colony forming units of granulocyte/macrophage (CFU-GM) were assessed after thawing, the impact of cell recovery on engraftment speed in patients was analyzed. The results showed that as compared with data provided by Umbilical Cord Blood Bark, the different cryopreservation time had no effect on yield of cord blood stem cells after thawing. The cell viability was (92.75 ± 2.55)% after thawing, the yields of TNC, CD34(+) cells and CFU-GM were 89.9%, 84.8% and 84.3%, compared with that of pre-freezing, their differences were statistically significant (P = 0.000), however, loss of cells had no effect on the time of neutrophils and platelets engraftment. The TNC and CD34(+)cell count after thawing correlated closely with that of pre-freezing (r = 0.954 and r = 0.931, P = 0.000), but CFU-GM content poorly correlated with that (r = 0.285, P = 0.223). It is concluded that cryopreservation and thawing process can damage the cord blood stem cells, leading to cell loss, but not affect transplant results.
Cell Count ; Cell Survival ; Cord Blood Stem Cell Transplantation ; methods ; Cryopreservation ; methods ; Fetal Blood ; cytology ; Humans

Antigens, CD34 ; Cell Count ; methods ; Flow Cytometry ; Humans

A microscopic examination of an appropriately prepared and well-stained blood smear by a knowledgeable laboratory professional is necessary and clinically useful in a number of circumstances and for a variety of reasons. In this article, an attempt is made to delineate the purpose and criteria for blood smear examination in a variety of circumstances that are encountered in everyday laboratory hematology practice. A blood smear scan serves to at least (a) verify the flagged automated hematology results and (b) determine if a manual differential leukocyte count needs to be performed. Blood smear examination/manual differential leukocyte count with complete blood count (CBC) provides the complete hematologic picture of the case, at least from the morphologic standpoint. Blood smear review with or without interpretation serves to ensure that no clinically significant finding is missed, besides providing diagnosis or diagnostic clue(s), particularly if and when interpreted by a physician.
Blood Cell Count ; Hematologic Tests/*methods ; Humans ; Leukocyte Count ; Leukocytes/cytology ; Medical Laboratory Personnel/standards

In the present study, the performance of a new blood cell separator (COBE Spectra LRS Turbo Version 7.0) and that of the previous version LRS version 5.1 in the collection efficiency (CE), collection rate and residual white blood cells during platelet collection from donors were compared. 232 units of platelet concentrates (n = 232) were evaluated and 163 units were collected with the Spectra LRS version 5.1 (Group A) and 69 units with the LRS turbo version 7.0 (Group B). Donor's blood cell counts and parameters, platelet yield, collection efficiency and residual leukocytes in platelet concentrates were analysed. Results showed that the platelet yield was higher in group B than that in group A: (2.90 +/- 1.1) x 10(11) versus (2.58 +/- 1.2) x 10(11), P < 0.001; residual WBCs were less than 5 x 10(6) in 99.4% of group A platelet concentrates and in 97.1% of group B platelet concentrates. Collection efficiency was higher in group B than in group A: 51.4 +/- 8.7 versus 43.6 +/- 6.3. A correlation between platelet count before collecting blood and platelet yield was observed in both groups. In conclusion, the Spectra LRS Turbo version 7.0 showed a higher platelet yield than that with LRS version 5.1. Higher platelet counts before collection allow a higher platelet yield.
Blood Platelets ; cytology ; Cell Separation ; instrumentation ; methods ; Humans ; Leukocyte Count ; Leukocytes ; cytology ; Platelet Count

OBJECTIVETo compare the effect of continuous and discontinuous density gradient centrifugation for purification of human pancreatic islets with COBE 2991 cell processor.

METHODSHuman pancreases were obtained from brain-dead donors and stored in cold UW solution. The connective tissues were removed from the pancreases, and the pancreatic ducts were perfused with a cold enzyme (Liberase). The islets were then separated by gentle mechanical dissociation and purified with discontinuous (10 pancreases) or continuous (8 pancreases) gradients of HCA-Ficoll in COBE 2991 cell processor. Samples were collected in duplicate for determination of the quantity of islets, islet equivalents (IEQ), and the purity.

RESULTSThe weights of the pancreases before and after connective tissue removal and pancreas duct perfusion, and the quantity of islets obtained (including islets quantity of different diameters and total IEQ) after dissociation were not significantly different. Continuous gradient of HCA-Ficoll, compared with discontinuous gradient, resulted in significantly greater final islet quantity (55,000 IEQ vs 206,000 IEQ, P=0.000) and islet purity (58.0%-/+8.0% vs 33.5%-/+10.3%, P=0.000) and also greater number of islets with a diameter lager than 200 microm (P<0.01).

CONCLUSIONContinuous density gradient centrifugation can be more effective than discontinuous gradient in islet purification.

BACKGROUND: Manual slide review (MSR) is usually triggered by the results of automated hematolgy analyzers, but each laboaratory has different ciriteria for MSR. This study was carried out to investigate the current status of MSR criteria of automated complete blood cell count (CBC) and white blood cell (WBC) differential results and to propose a basic guideline for MSR. METHODS: Total 111 laboratories were surveyed regarding MSR using questionnaires. The questionnaire asked: kinds of automated hematology analyzers used and the presence of criteria triggering MSR in seven categories: 1) CBC results, 2) 5 differential WBC counts, 3) 3 differential WBC counts, 4) automated reticulocyte counts, 5) delta check, 6) instrument flags (or messages), 7) clinical information (wards or diseases). Based on the survey results, we determined basic and extended criteria for MSR. With these criteria, we consulted nine hematology experts to get a consensus. RESULTS: All 111 laboratories had their own MSR criteria. Among 111 laboratories, 98 (88.3%) used more than three criteria for MSR including CBC results and 5-part WBC differential count results and 95 (85.6%) had criteria of flags triggering MSR. For MSR criteria with numeric values, the 10th, 50th, and 90th percentiles of upper and lower threshold values were obtained. The basic guideline for MSR was made. CONCLUSIONS: We proposed a basic guideline for MSR. This guideline would be helpful to hematology laboratories for their daily operation and providing more rapid and accurate CBC and WBC differential results.
Automation ; Blood Cell Count/instrumentation/*methods/standards ; Humans ; Laboratories, Hospital ; Leukocyte Count/instrumentation/*methods/standards ; Quality Control ; Questionnaires

In this brief review, some key issues related to cryopreservation of seeding cells, scaffolds, and engineered tissues are outlined. The importance of cryopreservation technology to the research and development of tissue engineered products is demonstrated. The biological or biochemical reaction rate must be reduced or completely shut off in order to preserve the tissue engineered products for a long period of time. Cryopreservation may be one of the possible approaches to the fulfillment of this requirement. Seeding cells are stored at low temperature. Tissue engineered scaffold products are usually lyophilized. Engineered tissues are preserved by vitreous cryopreservation technology.
Cell Count ; Cell Survival ; Cryopreservation ; methods ; Humans ; Tissue Engineering ; Tissue Preservation ; Tissue Survival

To investigate whether the RBC lysing solution can affect the results of relative enumeration of CD34(+) cells, 37 mobile peripheral blood apheresis products were stained using CD34-PE and CD45-FITC monoclone antibodies and RBCs were then lysed by two lysing solution commercially available (one named FACS Lysing Solution, FACS; another IOTest 3 Lysing Solution, IOTest) and one lysing solution self-prepared. After being processed by lyse-and-then-washed method, samples were detected by FACSC anto flow cytometer. The percentages of CD34(+) cells were determined based on ISHAGE gating strategy, forward and side scatter (FSC and SSC) characteristics, percentage of CD45(+) cells were recorded simultaneously. The results showed that by lyse-and-then-wash method, the percentages of CD34(+) cells in FACS-treated samples were significantly lower compared with that in IOTest-treated samples (0.50 +/- 0.42 vs 0.92 +/- 0.59, p = 0.004), but no statistical difference was observed between IOTest-treated and ourselves-prepared-treated samples. The intensities of FSC and SSC in cells of IOTest-treated sample were significantly higher compared with that in cells of FACS-treated sample (p < 0.01). The proportion of CD45(+) cells in IOTest-treated samples was lower than that in FACS-treated samples. The WBC count of samples was not correlated to the amount of CD34(+) cells (r(s) = 0.192, p = 0.357). It is concluded that the red cell lysing solution shows unexpected effect on detecting and counting CD34(+) cells, prudence should be taken to select such reagents at FCM performance.
Antigens, CD34 ; immunology ; Cell Count ; Cell Death ; Erythrocytes ; Flow Cytometry ; methods ; Humans ; Solutions ; pharmacology

OBJECTIVE: To compare two primary culture methods of human nasal epithelial (HNE) in vitro, and explore a suitable method to be used in further study. METHOD: Achievement ratio and growth curve of primarily cultural HNE by tissue piece culture were compared to those by isolated cell culture. Shape and appearance were observed and cellular sources were identified to get preliminary bionomics of HNE. RESULT: The isolated cell culture method (87.5%) was shown to be superior to tissue piece culture method (83.33%) by comparing achievement ratios, but no statistical significance was found (P > 0.05). The growth curve of isolated cell culture was higher than that of tissue piece culture. All cultured cells were confirmed coming from epithelial cells by observing shape, appearance and dyeing cytokeratin. CONCLUSION The isolated cell culture method is more suitable for primary culture due to its less promiscuity, faster proliferation, and more stable and reliable cell supply.
Cell Count ; Cell Culture Techniques ; methods ; Cells, Cultured ; Epithelial Cells ; cytology ; Humans ; Nasal Mucosa ; cytology