HemoScreen hematology analyzer compared to Sysmex XN for complete blood count, white blood cell differential, and detection of leukocyte abnormalities.

We compared a point-of-care HemoScreen hematology analyzer to an automated Sysmex XN analyzer for complete blood count (CBC) and white blood cell (WBC) differential, and evaluated its capacity to detect leukocyte abnormalities. A total of 100 K2-EDTA whole blood samples, median age 56 years (2 months to 92 years), were compared. For CBC and WBC differential we compared 74 samples with no confirmed abnormal leukocytes. For 26 samples both analyzers gave flagging regarding leukocytes and the accuracy of the flagging was compared. Abnormal leukocytes were confirmed with manual microscopy (200 cells). HemoScreen CBC and WBC differential were highly comparable to Sysmex XN for most of the essential parameters (r = 0.909-0.975). More variation was seen for basophil and monocyte counts (r = 0.452 and 0.753, respectively). Sysmex XN gave more false WBC abnormal flagging (n = 15 altogether) compared to HemoScreen. In addition, Sysmex XN, as well as HemoScreen, gave false WBC flagging for eight samples confirmed normal. The samples verified by microscopy review to truly contain leukocyte abnormalities (n = 18) were flagged abnormal with both analyzers. The specificity for analyzer flagging was 72% and 88% for Sysmex XN and HemoScreen, respectively. HemoScreen hematology analyzer is essentially comparable to Sysmex XN for CBC and WBC differential analysis. Most importantly, HemoScreen detected all the samples confirmed to include abnormal leukocytes. HemoScreen was less prone for false WBC flagging compared to Sysmex XN, thereafter requiring less microscopy review. These abilities increase its utility in small health care units. Studies with a larger number of abnormal leukocyte samples are needed to confirm HemoScreen performance.

Interchangeability of blood gas, electrolyte and metabolite results measured with point-of-care, blood gas and core laboratory analyzers.

BACKGROUND: The random use of point-of-care, blood gas and core laboratory analyzers to measure electrolytes and metabolites increases the variability in test results. This study was designed to determine whether these results performed on whole blood (point-of-care and blood gas) and plasma (core laboratory) platforms are interchangeable without a risk of clinically relevant discrepancies. METHODS: The interchangeability of the blood gas analysis, electrolytes, glucose, lactate and hemoglobin results performed with three stat platforms (i-STAT, Radiometer ABL 825, RapidLab 865) and two core laboratory platforms (Roche Modular P800 and Sysmex XE-2100) were evaluated using samples from critically ill patients. RESULTS: For pH, pCO(2), pO(2) and Ca(2+), good correlation (r-values 0.96-1.00) was observed for all comparative analyzers and the biases were within clinically acceptable limits. Potassium, sodium, glucose, lactate and hemoglobin measured with stat analyzers was highly correlated with measurements performed using the laboratory analyzers, r-values 0.89-1.00 and slopes 0.83-1.07. Mean differences with significant bias (p<0.0001) were found for sodium with blood gas analyzers and hemoglobin with i-STAT. CONCLUSIONS: The blood gas, K(+), Na(+), Ca(2+), glucose and lactate results measured with stat and core laboratory analyzers can be used in different clinical settings for critical care management. However, when monitoring small changes in sodium concentrations, the use of single analyzer is encouraged to avoid analytical differences (acceptance limit ± 2%) and misinterpretation of results measured with multiple analyzers. The users of the i-STAT at low hemoglobin values overdiagnose anaemia. Thus, prior to transfusion, the use of hemoglobin concentrations measured with laboratory analyzers is preferable.

Molecular markers implicating early malignant events in cervical carcinogenesis.

BACKGROUND: Human papillomavirus can induce a stepwise progression of precursor lesions to carcinoma. Sensitive and specific molecular markers are needed to identify the cervical lesions (CIN) at risk for this progression. hTERT activation could be one indicator of a point of no return in malignant progression. METHODS: The UT-DEC-1 cell line is an in vitro model for the study of human papillomavirus-induced progression. Using molecular mining, nine potential genes interlinking hTERT and viral oncogene expression with the phenotypical features of CIN2 were identified. After preliminary testing with real-time PCR, five genes were selected for further analysis: hTERT, DKC1, Bcl-2, S100A8, and S100A9. These proteins were also tested in a series of 120 CIN lesions using immunohistochemistry. RESULTS: Analysis of the mRNA expression of these genes at different cell passages revealed three time points with significant changes. hTERT, Bcl-2, and S100A9 were also overexpressed in CIN lesions, and the expression pattern changed during the progression toward CIN3 lesions. CONCLUSIONS: These identified time points that were combined with the mRNA overexpression of target genes matched events previously shown to be important in the progression toward malignancy: (a) the viral integration into the cell genome and episome loss; (b) the selection of cells with an acquired growth advantage and ability to maintain telomerase activity; and (c) the final stage of malignancy with permanently upregulated telomerase. IMPACT: hTERT, Bcl-2, and S100A9 together might compose a potential prognostic marker panel for the assessment of CIN lesions. These results, however, need further validation in prospective clinical settings. (c)2010 AACR.

Radiation-induced effects on telomerase in gynecological cancer cell lines with different radiosensitivity and repair capacity.

PURPOSE: Telomerase activation in response to irradiation might enhance the radioresistance of cells. Thus, we have investigated radiation-induced effects on telomerase in six gynecological cancer cell lines, with different intrinsic radiosensitivity and capacity for sublethal damage repair (SLDR). MATERIALS AND METHODS: Three endometrial adenocarcinoma (UM-EC-1, UT-EC-2B and UT-EC-3) and three vulvar squamous cell carcinoma (A431, UM-SCV-2 and UM-SCV-7) cell lines were irradiated with doses of 5, 10 and 25 Gy and the effects on telomerase were evaluated at 0.5, 6, 24 and 48 h post-irradiation. Telomerase activity was quantitatively measured by SYBR Green real-time telomeric repeat amplification protocol. RESULTS: The most radioresistant cell line A431 had the strongest stimulatory effects (approximately 2.0 - 2.5-fold) on telomerase activity 24 and 48 h post-irradiation with the highest radiation doses. In contrast to that, telomerase activities in the highly radiosensitive cell line UT-EC-2B remained below the basal level throughout the 48-h period of post-irradiation with the highest doses, and even a decline to approximately 50% of the basal level was found 24 h after exposure. In other cell lines being either moderately or highly radiation resistant, telomerase activity levels in response to irradiation remained mainly at the basal level or gradually increased. CONCLUSIONS: The present findings indicate that there might be a connection between the radiation-induced telomerase response and radiosensitivity. However, no correlation was found between the radiation-induced effects on telomerase and the sublethal damage repair capacity of the cells.

Long-term suppression of telomerase expression in HeLa cell clones, transfected with an expression vector carrying siRNA targeting hTERT mRNA.

HeLa cell cultures were used as model systems for small interfering RNA (siRNA) induced knockdown of mRNA expression of the human telomerase catalytic subunit, telomerase reverse transcriptase (hTERT). Four 21-bp siRNAs targeting different sites of the hTERT mRNA were designed, and the siRNA molecules produced by a T7 transcription system in vitro. In transient transfection assays on HeLa cells, only one of the tested siRNAs produced a potent knockdown effect on hTERT mRNA expression, associated with the suppression of telomerase activity (both reduced by approximately 50%). An expression vector encoding a hairpin siRNA against the effective hTERT mRNA target site was generated, and HeLa clones stably expressing hTERT-specific siRNA were created. Two clones showed extremely reduced hTERT mRNA expression, associated with unusually short telomeres, the inhibition of cell growth and the induction of senescence and apoptosis. Thus, there was obvious loss of viability in cells lacking hTERT expression and carrying short telomeres. This was most prominent in the clone that showed prolonged reductions (over two months) in both hTERT expression and telomerase activity. Thus, our data clearly show that long-term suppression of telomerase expression by siRNA is an attainable goal, at least in a HeLa cell model system.