Reducing Laboratory Turnaround Time in Patients With Acute Stroke and the Lack of Impact on Time to Reperfusion Therapy.

CONTEXT.­: Timely reperfusion improves the recovery of patients with acute ischemic stroke. Laboratory results are crucial to guide treatment decisions in patients when abnormal laboratory tests are suspected. OBJECTIVE.­: To implement a new laboratory workflow for acute stroke patients and compare laboratory turnaround time (TAT) preimplementation and postimplementation. DESIGN.­: We conducted a retrospective pre-post intervention study of patients with suspected acute stroke during the 4-month periods before and after the implementation of a new laboratory workflow process. The improvement process included relocating the specimen registration site, laboratory notification before specimen arrival, a color-coding system on tubes, timing at all processes, and eliminating the smear review if platelets were normal. TATs of the laboratory and door-to-clinical intervention times before and after the improvement process were compared. RESULTS.­: Postintervention, median specimen transportation time decreased from 11 (interquartile range [IQR], 8.4-16.4) to 9 minutes (IQR, 6.3-12.8), P < .001. The intralaboratory and total TATs of complete blood cell count, coagulation tests, and creatinine significantly decreased (P < .001 for all). Blood drawn-to-laboratory reported time decreased from 43 (IQR, 36.0-51.5) to 33 minutes (IQR, 29.2-35.8, P < .001). However, door-to-needle time for thrombolysis and door-to-puncture time and door-to-recanalization time for mechanical thrombectomy were not statistically different (P = .11, .69, and .50, respectively). CONCLUSIONS.­: The new laboratory workflow significantly decreased transportation time, TAT of individual tests, and the blood drawn-to-laboratory reported time. However, the time to treatment of acute ischemic stroke patients was not different between preimplementation and postimplementation.

A retrospective review of on-admission factors on attainment of therapeutic serum concentrations of magnesium sulfate in women treated for a diagnosis of preeclampsia.

Introduction: There is little information on the effect of maternal characteristics and on-admission laboratory parameters to the therapeutic serum magnesium sulfate (MgSO4) levels in women with preeclampsia (PE). We sought to identify factors that may predict timely attainment of therapeutic serum magnesium levels after intravenous administration for seizure prophylaxis.Materials and methods: On-admission factors of 360 women with PE who received intravenous MgSO4 (4-g loading and 2-g/h maintenance) for seizure prophylaxis were retrospectively reviewed. Parameters of those who attained therapeutic serum concentrations (4.8-8.4 mg/dL) within 2 h (Group A) and those who did not (Group B) were compared.Results: There was no seizure or magnesium toxicity in this cohort. Median (min-max) level of serum magnesium was 4.3 (2.5-8.4) mg/dL. Women in Group A (n = 105) had lower gestational age, body mass index (BMI), and platelets count, higher blood urea nitrogen (BUN), serum creatinine, uric acid, direct bilirubin, aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase, prothrombin, and partial thromboplastin times than those in Group B (n = 255) (p < .05). Women with mild PE were less likely to attain therapeutic serum magnesium levels compared with those with severe phenotypes (adjusted OR 23.57, 95% CI 8.20-67.76 versus adjusted OR 14.72, 95% CI 3.56-60.89, respectively; p < .05), which may be explained by their significantly lower serum BUN and uric acid (p < .05).Conclusions: On-admission factors, especially BMI and renal clearance indices, of women with PE may affect timely attainment of therapeutic serum magnesium levels. Validation of its clinical impact requires further study focusing on women with severe PE.

Increased effectiveness of urinalysis testing via the integration of automated instrumentation, the lean management approach, and autoverification.

BACKGROUND: In 2014, the Department of Clinical Pathology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand developed and implemented a new process that uses fully automated instrumentation, the lean management approach, and autoverification to improve the productivity and efficiency of the urinalysis workflow process. The aim of this study was to evaluate analytical turnaround time compared with our old urinalysis workflow process and our new urinalysis workflow process that was launched in 2014. METHODS: This study was performed at the Central Laboratory of our center during June 2017 using data collected from the July 2012 (old process) and July 2014 (new process) study periods. We used our laboratory information system to compute and analyze turnaround time of urinalysis tests, and those results were compared between processes. RESULTS: The 90th percentile turnaround time in overall data was dramatically decreased from approximately 60 minutes in 2012 to <50 minutes in 2014. The mean during both 6:00 am to 9:00 am and 9:00 am to 12:00 pm was approximately 42 minutes in 2012; however, that duration was reduced to approximately 30 minutes for both of those time periods in 2014. Specimens within 60 minutes in both intervals increase from approximately 80% to more than 90%. CONCLUSION: The results of this study revealed our new urinalysis workflow process that incorporates fully automated instrumentation, the lean management approach, and autoverification to be effective for significantly increasing productivity as measured by analytical turnaround time and removing 1 staff to another section.

Anion gap reference intervals show instrument dependence and weak correlation with albumin levels.

BACKGROUND: Anion gap (AG) aids the differential diagnosis of acid-base disorders. Its value has decreased, because of new analytical methods. Our goal was to compare AG reference intervals for different instruments and Southeast Asian populations. METHODS: We studied AG at three hospitals. One used the cobas 8000; two others, the Architect c16000. We included consecutive adults ≥18 years whose samples were sent for electrolytes and creatinine. We assessed AG for all patients and patients with normal electrolytes. RESULTS: AG means differed significantly (P < 0.001) between the three hospitals for all patients and the normal electrolyte subgroup. AG reference intervals from all patients were 9-19, 5-15, and 5-15 mmol/L, and for the normal electrolyte subgroup, 10-17, 6-14, and 5-12 mmol/L, respectively. Compared to the normal albumin group, hypoalbuminemia patients showed lower AG in two hospitals (P < 0.001, P = 0.03), whereas patients with hyperalbuminemia demonstrated higher AG in all three hospitals (P < 0.001). CONCLUSIONS: Different instruments produce different AGs. There is a weak correlation between albumin levels and AG. Laboratorians should verify reference intervals used when detecting laboratory errors and assisting clinicians in the differential diagnosis of acid base disorders and other medical conditions.

Altered profile of circulating microparticles in nonvalvular atrial fibrillation.

BACKGROUND: Nonvalvular atrial fibrillation (AF) is the most common cardiac arrhythmia, and it is associated with the prothrombotic state. Circulating microparticles (cMPs) are membrane vesicles that are shed from many cell types in response to cell activation and cell apoptosis. Several studies reported that cMPs may play a role in the hypercoagulable state that can be observed in patients with AF. The aim of this study was to determine the levels of total cMPs and characterize their cellular origins in AF patients. METHODS: Atotal of 66 AF patients and 33 healthy controls were enrolled. This study investigated total cMP levels and their cellular origin in AF patients using polychromatic flow cytometry. RESULTS: AF patients had significantly higher levels of total cMPs (median 36.38, interquartile range [IQR] 21.16-68.50 × 105 counts/mL vs median 15.21, IQR 9.91-30.86 × 105 counts/mL; P = 0.004), platelet-derived MPs (PMPs) (median 10.61, IQR 6.55-18.04 × 105 counts/mL vs median 7.83, IQR 4.44-10.26 × 10/mL; P = 0.009), and endothelial-derived MPs (EMPs CD31+ CD41-) (median 2.94, IQR 1.78-0.60 × 105 counts/mL vs median 1.16, IQR 0.71-2.30 × 105 counts/mL; P = 0.001) than healthy controls after adjusting for potential confounders. Phosphatidylserine positive MP (PS + MP) levels were similar compared between AF patients and healthy controls. CONCLUSION: The results of this study revealed a marked increase in total cMP levels, and evidence of elevated endothelial damage and platelet activation, as demonstrated by increased PMP and EMP levels, in AF patients. Additional study is needed to further elucidate the role of cMPs (PMPs and EMPs) in the pathophysiology of and the complications associated with AF.

Hemoglobin A1c Levels Are Slightly but Significantly Lower in Normoglycemic Subjects With the Hemoglobin E Phenotype.

Hb mutations can alter the structure, behavior, stability, or quantity of the globin chain produced. Some Hb variants shorten the erythrocyte life span, resulting in physiologically lower hemoglobin A1c (HbA1c) levels. The hemoglobin E (HbE) phenotype involves a single-nucleotide polymorphism that reduces ß-globin chain synthesis. We compared the HbA1c levels of subjects with normal Hb (HbAA; N=131) and HbE (N=148) phenotypes, examining potential hematological and biochemical factors contributing to differences in HbA1c levels. All had normal fasting plasma glucose (<5.6 mmol/L), AST, ALT, and creatinine levels. Mean±SD HbA1c levels differed between HbAA and HbE subjects: 5.5±0.3% and 5.3±0.3% (P<0.001) according to an immunoassay, and 5.5±0.3% and 5.3±0.3% (P<0.001) according to cation-exchange HPLC, respectively. In multiple logistic regression, only mean corpuscular volume (P<0.001) contributed to the difference in HbA1c levels between groups. Although a 0.2% difference in HbA1c is relatively small and unlikely to alter clinical decisions, epidemiologically, this can lead to misclassification of a significant proportion of the population, especially since the threshold of non-diabetes HbA1c (≤5.6%) falls very close to the HbA1c median of the general population.

UriSed 3 and UX-2000 automated urine sediment analyzers vs manual microscopic method: A comparative performance analysis.

BACKGROUND: Fully automated urine analyzers now play an important role in routine urinalysis in most laboratories. The recently introduced UriSed 3 has a new automated digital imaging urine sediment analyzer with a phase contrast feature. The aim of this study was to compare the performance of the UriSed 3 and UX-2000 automated urine sediment analyzers with each other and with the results of the manual microscopic method. METHODS: Two hundred seventy-seven (277) samples of leftover fresh urine from our hospital's central laboratory were evaluated by two automated urine sediment analyzers-UriSed 3 and UX-2000. The results of urine sediment analysis were compared between the two automated analyzers and against the results of the manual microscopic method. RESULTS: Both devices demonstrated excellent agreement for quantitative measurement of red blood cells and white blood cells. UX-2000 had a lower coefficient correlation and demonstrated slightly lower agreement for squamous epithelial cells. Regarding semiquantitative analysis, both machines demonstrated very good concordance, with all applicable rates within one grade difference of the other machine. UriSed 3 had higher sensitivity for small round cells, while UX-2000 showed greater sensitivity for detecting bacteria and hyaline casts. UriSed 3 demonstrated slightly better specificity, especially in the detection of hyaline and pathological casts. CONCLUSIONS: Both instruments had nearly similar performance for red blood cells and white blood cells measurement. UriSed 3 was more reliable for measuring squamous epithelial cells and small round cells, while the UX-2000 was more accurate for detecting bacteria and hyaline casts.

Reference Values for Umbilical Cord Blood Gases of Newborns Delivered by Elective Cesarean Section.

BACKGROUND: Umbilical cord blood gas values are better indicators of perinatal asphyxia than Apgar scores. Many studies have reported normal ranges of umbilical cord blood gases, which vary greatly due to many factors. This study aimed to establish the reference values of umbilical cord blood gases of normal cesarean newborns in a university hospital setting. MATERIAL AND METHOD: Blood samples from the umbilical artery and vein were collected from 160 newborns delivered by elective cesarean section. The indications for caesarean section were not due to fetal distress, intrauterine growth retardation, or non-reassuring fetal heart rate. The blood samples were collected immediately after birth in the operating room and then sent for blood-gas analysis. The blood-gas values were statistically analyzed and reported. RESULTS: The cord blood collected from 160 newborns was analyzed in this study. Seventy-eight percent (115) of the parturients were hypotensive before delivery. All Apgar scores at one and five minutes after delivery were at least 7. The calculated reference range of the umbilical arterial pH was 7.18-7.42, of pO2was 6.43-29.43 mmHg, of pCO2was 33.44-66.56 mmHg, and of HCO3was 15.60-30.70 mEq/L. The reference range obtained for the umbilical venous pH was 7.28-7.44,for pO2was 13.97-37.13 mmHg, for pCO2was 30.70-57.0 mmHg, and for HCO3was 18.50-29.90 mEq/L. CONCLUSION: The study determined normal reference values as a result of umbilical cord blood gas analyses.

Performance Evaluation and Comparison of the Fully Automated Urinalysis Analyzers UX-2000 and Cobas 6500.

OBJECTIVE: To evaluate and compare the performances of the automated urinalysis devices UX-2000 and Cobas 6500. METHOD: A total of 258 urine specimens were collected from the routine specimen workload. We analyzed all specimens on both automated instruments and recorded the turnaround time from each method. Physical, chemical, and sedimentary urine components were compared between the automated and the manual method for each analyzer. RESULTS: The correlation of urine physical/chemical properties between the 2 instruments was excellent. The Cobas 6500 instrument demonstrated a higher level of agreement for red blood cells (Cobas 6500:R= 0.94; UX-2000:R= 0.78) and white blood cells (Cobas 6500:R= 0.95; UX-2000:R= 0.85). The UX-2000 demonstrated higher sensitivity for small round cells, hyaline casts, pathological casts, and bacteria. The median turnaround time was 1.5 minutes and 8.5 minutes for the Cobas 6500 and UX-2000, respectively. CONCLUSIONS: The 2 devices showed similar performance in technical evaluation; they each reduce workload and increase time saving. However, manual examination by technicians is recommended for pathological specimens.

Maternal Vitamin D Status and Its Related Factors in Pregnant Women in Bangkok, Thailand.

BACKGROUND: There are few data focusing on the prevalence of vitamin D deficiency in tropical countries. OBJECTIVES: We determined the vitamin D status in pregnant women and examined the factors associated with vitamin D deficiency. DESIGN AND METHODS: A cross-sectional study of 147 pregnant Thai women aged 18-45 years at Siriraj Hospital (a university hospital in Bangkok, Thailand) was undertaken. Clinical data and plasma levels of 25-hydroxyvitamin D [25(OH)D], intact parathyroid hormone (iPTH), calcium, albumin, phosphate and magnesium were obtained in pregnant women at delivery. RESULTS: The prevalence of hypovitaminosis D [defined as 25(OH)D <75 nmol/L] in pregnant women at delivery was 75.5% (95% confidence interval (CI), 67.7-82.2%). Of these, vitamin D insufficiency [defined as 25(OH)D 50-74.9 nmol/L] was found in 41.5% (95% CI, 33.4-49.9%) and vitamin D deficiency [25(OH)D <50 nmol/L] was found in 34.0% (95% CI, 26.4-42.3%) of women. The mean 25(OH)D concentration was 61.6 ± 19.3 nmol/L. The correlation between 25(OH)D and iPTH was weak (r = -0.29, P<0.01). Factors associated with vitamin D deficiency by multiple logistic regression were: pre-pregnancy body mass index (BMI in kg/m2, odds ratio (OR), 0.88, 95% CI 0.80-0.97, P = 0.01) and season of blood collection (winter vs. rainy, OR, 2.62, 95% CI 1.18-5.85, P = 0.02). CONCLUSIONS: Vitamin D deficiency is common among pregnant Thai women. The prevalence of vitamin D deficiency increased in women who had a lower pre-pregnancy BMI and whose blood was collected in the winter. Vitamin D supplementation may need to be implemented as routine antenatal care.

Hypovitaminosis D in healthy children in Central Thailand: prevalence and risk factors.

BACKGROUND: There are limited data regarding the prevalence and risk factors relating to hypovitaminosis D in children of Thailand, a tropical country with abundant sunlight. The objective of this study was to assess the prevalence of hypovitaminosis D and examine factors associated with hypovitaminosis D in school-aged children in Bangkok, Thailand - a centrally located capital city. METHODS: This cross-sectional study evaluated 159 healthy children (33.3% boys and 66.7% girls), aged 6 to 12 years, in Bangkok, Thailand (located at 13.45°N). Fasting plasma samples were examined for total 25-hydroxyvitamin D [25(OH)D] using electrochemiluminescence immunoassay. Demographic characteristics (age, sex, household income), past medical history (birth weight, allergic diseases, hospitalization), amount of sun exposure, anthropometric data, and selected biochemical tests were used to investigate for factors associated with hypovitaminosis D. RESULTS: Overall, the mean ± SD level of plasma 25(OH)D was 64.0 ± 15.1 nmol/L. Hypovitaminosis D (< 75 nmol/L) was presented in 79.2% of subjects. Of these, the prevalence of vitamin D insufficiency and vitamin D deficiency were 59.7% and 19.5%, respectively. In univariate analysis, children with hypovitaminosis D (< 75 nmol/L) had a higher mean body mass index (BMI) percentile than the vitamin D-sufficient group (56.7 ± 33.9 vs. 42.6 ± 36.0; P-value = 0.04). Plasma PTH levels in the children with hypovitaminosis D were significantly higher than in the children with normal levels of vitamin D (4.34 ± 1.38 vs 3.78 ± 1.25 pmol/L; P-value = 0.04). In multivariate analysis, high BMI percentile and high PTH concentration were the parameters associated with 25(OH)D level < 75 nmol/L. CONCLUSION: The prevalence of hypovitaminosis D in healthy Thai children is very high, despite their exposure to sunlight, and that prevalence increases in children with a high BMI percentile. As a result, a formal recommendation for vitamin D supplementation in Thai children should be considered.

Optimal criteria for microscopic review of urinalysis following use of automated urine analyzer.

BACKGROUND: The Sysmex UX-2000 is a new, fully automated integrated urine analyzer. This device analyzes all physical and chemical characteristics of urine and sediments in urine on single platform. Because sediment analysis by fluorescent flow cytometry has limited ability to classify some formed elements present in urine (e.g., casts), laboratories should develop criteria for manual microscopic examination of urinalysis following the use of the automated urine analyzer. METHODS: 399 urine samples were collected from routine workload. All samples were analyzed on the automated analyzer and were then compared to the results of the manual microscopic method to establish optimal criteria. Another set of 599 samples was then used to validate the optimized criteria. The efficiency of criteria and review rate were calculated. The false-positive and false-negative cases were enumerated and clarified. RESULTS: We can set 11 rules which are related to the parameters categorized by the UX-2000, including cells, casts, crystals, organisms, sperm, and flags. After optimizing the rules, the review rate was 54.1% and the false-negative rate was 2.8%. CONCLUSIONS: The combination of both UX-2000 and manual microscopic method obtain the best results. The UX-2000 improves efficiency by reducing the time and labor associated with the specimen analysis process.

Isolation, characterization, and transplantation of cardiac endothelial cells.

Isolation and ex vivo expansion of cardiac endothelial cells have been a recurrent challenge due to difficulties in isolation, cell heterogeneity, lack of specific markers to identify myocardial endothelial cells, and inadequate conditions to maintain long-term cultures. Herein, we developed a method for isolation, characterization, and expansion of cardiac endothelial cells applicable to study endothelial cell biology and clinical applications such as neoangiogenesis. First, we dissociated the cells from murine heart by mechanical disaggregation and enzymatic digestion. Then, we used flow cytometry coupled with specific markers to isolate endothelial cells from murine hearts. CD45+ cells were gated out to eliminate the hematopoietic cells. CD31+/Sca-1+ cells were isolated as endothelial cells. Cells isolated from atrium grew faster than those from ventricle. Cardiac endothelial cells maintain endothelial cell function such as vascular tube formation and acetylated-LDL uptake in vitro. Finally, cardiac endothelial cells formed microvessels in dorsal matrigel plug and engrafted in cardiac microvessels following intravenous and intra-arterial injections. In conclusion, our multicolor flow cytometry method is an effective method to analyze and purify endothelial cells from murine heart, which in turn can be ex vivo expanded to study the biology of endothelial cells or for clinical applications such as therapeutic angiogenesis.

Should acidification of urine be performed before the analysis of calcium, phosphate and magnesium in the presence of crystals?

BACKGROUND: Acidification of urine has been recommended before testing for calcium, phosphate, and magnesium. We investigated the necessity of pre-analytical acidification in both crystallized and non-crystallized urine samples. METHODS: From 130 urine samples obtained via routine urine analysis, 65 (50%) samples were classified as non-crystallized. All samples were divided into three groups: untreated samples, acidified samples with HCl, and acidified samples after 1h room-temperature incubation. Urine samples were measured for calcium, phosphate, magnesium, and creatinine using Modular P800 and were examined for crystals using light microscopy. RESULTS: In crystallized samples, acidified samples with 1h incubation had significantly higher Ca/Cr, P/Cr, and Mg/Cr than did untreated samples with mean differences of 0.04, 0.03, and 0.01 mg/mg, respectively (P<0.001). In acidified samples that were analyzed immediately, crystallized samples had lower calcium concentrations than those of acidified samples with 1h incubation and a mean difference of 0.21 mg/dl (P = 0.025). None of the sample differences which exceeded the critical difference of urinary Ca, P and Mg was observed. CONCLUSIONS: Acidification of urine should be performed before the measurement of Ca, P, and Mg in the presence of urinary crystals. However, the lack of an acidification process does not result in a clinically significant change.

Validation and optimization of criteria for manual smear review following automated blood cell analysis in a large university hospital.

CONTEXT: Each laboratory should have criteria for manual smear review that limit workload without affecting patient care. The International Consensus Group for Hematology Review established guidelines for action after automated blood cell analysis in 2005. OBJECTIVE: To compare the consensus group criteria with our laboratory criteria and optimize them for better efficiency. DESIGN: A total of 2114 first-time samples were collected consecutively from daily workload and were used to compare 2 criteria as well as establish the optimized criteria. Another set of 891 samples was used to validate the optimized criteria. All samples were run on either Sysmex XE-5000 or Coulter LH750 hematology analyzers and were investigated by manual smear review. The efficiency of each set of criteria was compared and optimized to obtain better efficiency, an acceptable review rate, and a low false-negative rate. RESULTS: From 2114 samples, 368 (17.40%) had positive smear results. Compared with that of our laboratory criteria, the efficiency of the consensus group criteria was higher (83.63% versus 78.86%, P < .001), the review rate was higher (29.33% versus 22.37%, P < .001), and the false-negative rate was lower (2.22% versus 8.09%, P < .001). After optimizing the rules, we obtained an efficiency of 87.13%, a review rate of 24.22%, and a false-negative rate of 2.98%. We validated the optimized criteria with another set of samples, and the efficiency, review rate, and false-negative rate were 87.32%, 25.25%, and 1.12%, respectively. CONCLUSIONS: Each laboratory should verify the criteria for smear review, based on the International Consensus Group for Hematology Review, and optimize them to maximize efficiency.

B-type natriuretic peptide not TIMI risk score predicts death after acute coronary syndrome.

BACKGROUND: The TIMI risk score is a clinical scoring system used to predict mortality in patients following an acute coronary syndrome (ACS). B-type natriuretic peptide (BNP) has also been found to be useful in this setting. METHODS: 80 patients (35 men, 45 women) mean (SD) age 70.68 (9.90) years with ACS were studied. Blood was drawn within 12 hours after the onset of ACS and the blood level of BNP was measured using Biosite Triage Cardioprofiler Panel (Biosite Inc., San Diego, CA, USA). Patient's TIMI risk score was recorded and patients were stratified into low (0 - 2), intermediate (3 - 4), and high-risk (5 - 7) groups. RESULTS: Overall mortality at 18 months was 20% and was related to BNP levels but not the higher TIMI risk scores. Higher BNP levels were related to decreased survival (median (range) ng/mL, survivors: 166 (5 - 4,710) vs. deceased: 1,093.5 (71.3 - 4,840), p < 0.001). The optimal cutoff for the prediction of survival was 250 ng/mL. ACS patients with BNP over this cutoff have demonstrated the lower survival (log rank p < 0.001). CONCLUSIONS: BNP measurement within the first 12 hours following an ACS is more easily performed and is more accurate than a clinical risk score at predicting long term mortality.

Isolation and characterization of neural crest-derived stem cells from dental pulp of neonatal mice.

Dental pulp stem cells (DPSCs) are shown to reside within the tooth and play an important role in dentin regeneration. DPSCs were first isolated and characterized from human teeth and most studies have focused on using this adult stem cell for clinical applications. However, mouse DPSCs have not been well characterized and their origin(s) have not yet been elucidated. Herein we examined if murine DPSCs are neural crest derived and determined their in vitro and in vivo capacity. DPSCs from neonatal murine tooth pulp expressed embryonic stem cell and neural crest related genes, but lacked expression of mesodermal genes. Cells isolated from the Wnt1-Cre/R26R-LacZ model, a reporter of neural crest-derived tissues, indicated that DPSCs were Wnt1-marked and therefore of neural crest origin. Clonal DPSCs showed multi-differentiation in neural crest lineage for odontoblasts, chondrocytes, adipocytes, neurons, and smooth muscles. Following in vivo subcutaneous transplantation with hydroxyapatite/tricalcium phosphate, based on tissue/cell morphology and specific antibody staining, the clones differentiated into odontoblast-like cells and produced dentin-like structure. Conversely, bone marrow stromal cells (BMSCs) gave rise to osteoblast-like cells and generated bone-like structure. Interestingly, the capillary distribution in the DPSC transplants showed close proximity to odontoblasts whereas in the BMSC transplants bone condensations were distant to capillaries resembling dentinogenesis in the former vs. osteogenesis in the latter. Thus we demonstrate the existence of neural crest-derived DPSCs with differentiation capacity into cranial mesenchymal tissues and other neural crest-derived tissues. In turn, DPSCs hold promise as a source for regenerating cranial mesenchyme and other neural crest derived tissues.