Hypoxia improves hair inductivity of dermal papilla cells via nuclear NADPH oxidase 4-mediated reactive oxygen species generation'.

BACKGROUND: Dermal papilla cells (DPCs) play a key role in hair regeneration and morphogenesis. Therefore, tremendous efforts have been made to promote DPC hair inductivity. OBJECTIVES: The aim of this study was to investigate the mitogenic and hair inductive effects of hypoxia on DPCs and examine the underlying mechanism of hypoxia-induced stimulation of DPCs. METHODS: DPCs' hair inductivity was examined under normoxia (20% O2 ) and hypoxia (2% O2 ). RESULTS: Hypoxia significantly increased the proliferation and delayed senescence of DPCs via Akt phosphorylation and downstream pathways. Hypoxia upregulated growth factor secretion of DPCs through the mitogen-activated protein kinase pathway. Hypoxia-preconditioned DPCs induced the telogen-to-anagen transition in C3 H mice, and also enhanced hair neogenesis in a hair reconstitution assay. Injected green fluorescent protein-labelled DPCs migrated to the outer root sheath of the hair follicle, and hypoxia-preconditioning increased survival and migration of DPCs in vivo. Conditioned medium obtained from hypoxia increased the hair length of mouse vibrissa follicles via upregulation of alkaline phosphatase, vascular endothelial growth factor, and glial cell line-derived neurotrophic factor. We examined the mechanism of this hypoxia-induced stimulation, and found that reactive oxygen species (ROS) play a key role. For example, inhibition of ROS generation by N-acetylcysteine or diphenyleneiodonium treatment attenuated DPCs' hypoxia-induced stimulation, but treatment with ROS donors induced mitogenic effects and anagen transition. NADPH oxidase 4 is highly expressed in the DPC nuclear region, and NOX4 knockout by CRISPR-Cas9 attenuated the hypoxia-induced stimulation of DPCs. CONCLUSIONS: Our results suggest that DPC culture under hypoxia has great advantages over normoxia, and is a novel solution for producing DPCs for cell therapy. What's already known about this topic? Dermal papilla cells (DPCs) play a key role in hair regeneration and morphogenesis, but they are difficult to isolate and expand for use in cell therapy. Tremendous efforts have been made to increase proliferation of DPCs and promote their hair formation ability. What does this study add? Hypoxia (2% O2 ) culture of DPCs increases proliferation, delays senescence and enhances hair inductivity of DPCs. Reactive oxygen species play a key role in hypoxia-induced stimulation of DPC. What is the translational message? Preconditioning DPCs under hypoxia improves their hair regenerative potential, and is a novel solution for producing DPCs for cell therapy to treat hair loss.

Revisiting the diagnostic criteria of clinical chorioamnionitis in preterm birth.

OBJECTIVE: To re-evaluate the utility of the conventional criteria for clinical chorioamnionitis in the prediction of early-onset neonatal sepsis (EONS) in preterm birth. DESIGN: Retrospective cohort study. SETTING: Seoul, Republic of Korea. SAMPLE: A total of 1468 singleton births between 24 and 34 weeks due to preterm labour (n = 713) or preterm prelabour rupture of membranes (n = 755). METHOD: We evaluated three diagnostic categories of clinical chorioamnionitis: Criteria 1, conventional criteria; Criteria 2, combination of any three conventional parameters without prerequisite fever; Criteria 3, Criteria 1 plus positive maternal C-reactive protein and neutrophil left-shift into minor criteria. EONS included proven or suspected sepsis within 7 days following birth. Neonatal morbidity and mortality of EONS were also reviewed. MAIN OUTCOME MEASURES: Diagnostic performance of three combinations. RESULTS: The prevalence of EONS was 13.8%. Among 203 cases of EONS, maternal manifestation of clinical chorioamnionitis by criteria 1 was evident in only one out of seven, indicating 15.3% sensitivity for EONS prediction. However, with application of criteria 2, sensitivity significantly increased to 34.0%, while compromising specificity from 92.3% to 78.7%. Criteria 3 showed similar diagnostic performance compared with criteria 1 (sensitivity 16.7%, specificity 91.6%). Overall, neonatal mortality and neonatal composite morbidity in EONS were 14.9% and 67.8%, respectively, and there was no difference in neonatal morbidity and mortality between neonates whose mothers showed fever as a sign of clinical chorioamnionitis and those whose mothers did not. CONCLUSION: The renouncement of fever as a prerequisite for the criteria of clinical chorioamnionitis could increase sensitivity for the identification of EONS, a serious outcome of preterm birth. TWEETABLE ABSTRACT: The renouncement of fever as an essential can increase sensitivity for prediction of neonatal sepsis.

Surface modulation and back reflection from foil targets irradiated by a Petawatt femtosecond laser pulse at oblique incidence.

A significant level of back reflected laser energy was measured during the interaction of ultra-short, high contrast PW laser pulses with solid targets at 30° incidence. 2D PIC simulations carried out for the experimental conditions show that at the laser-target interface a dynamic regular structure is generated during the interaction, which acts as a grating (quasi-grating) and reflects back a significant amount of incident laser energy. With increasing laser intensity above 1018 W/cm2 the back reflected fraction increases due to the growth of the surface modulation to larger amplitudes. Above 1020 W/cm2 this increase results in the partial destruction of the quasi-grating structure and, hence, in the saturation of the back reflection efficiency. The PIC simulation results are in good agreement with the experimental findings, and, additionally, demonstrate that in presence of a small amount of pre-plasma this regular structure will be smeared out and the back reflection reduced.

A Study of Piezoelectric Field Related Strain Difference in GaN-Based Blue Light-Emitting Diodes Grown on Silicon(111) and Sapphire Substrates.

We investigate the strain difference in InGaN/GaN multiple quantum wells of blue light-emitting diode (LED) structures grown on silicon(1 11) and c-plane sapphire substrates by comparing the strength of piezo-electric fields in MQWs. The piezo-electric fields for two LED samples grown on silicon and sapphire substrates are measured by using the reverse-bias electro-reflectance (ER) spectroscopy. The flat-band voltage is obtained by measuring the applied reverse bias voltage that induces a phase inversion in the ER spectra, which is used to calculate the strength of piezo-electric fields. The piezo-electric field is determined to be 1.36 MV/cm for the LED on silicon substrate and 1.83 MV/cm for the LED on sapphire substrate. The ER measurement results indicate that the strain-induced piezo-electric field is greatly reduced in the LED grown on silicon substrates consistent with previous strain measurement results by micro-Raman spectroscopy and high-resolution transmission electron microscopy.

Association between eNOS polymorphisms and risk of coronary artery disease in a Korean population: a meta-analysis.

Coronary artery disease (CAD), a multifactorial disease, is a common cause of mortality in humans. Polymorphisms in the endothelial nitric oxide synthase (eNOS) gene (-786T>C, 4a4b, and 894G>T) have been previously associated with increased CAD risk. However, the sample size of this previous study was too small and limited to comprehensively define an association between eNOS polymorphisms and CAD; therefore, this analysis was duplicated with a larger population. The study was conducted on 559 patients with CAD and 574 healthy controls. Genetic DNA was extracted using the commercial G-DEX blood extraction kit and statistical analyses were performed on the GraphPad prism 4.0 and MedCalc 12.0 statistical software platforms. No single variant of the eNOS polymorphism was associated with CAD risk. The combination genotypes of eNOS -786TT/4a4b+4a4a [adjusted odds ratio (AOR) = 0.122; 95% confidence interval (CI): 0.042-0.358] and eNOS -786TC+CC/4b4b (AOR = 0.379; 95%CI: 0.147-0.979) were associated with decreased CAD incidence. Haplotype analysis revealed that the T-4a haplotype of eNOS -786T>C and 4a4b exerted a protective effect against CAD. The association between eNOS -786T>C and increased CAD risk was not replicated in this (larger) population. However, some combined genotypes showed a meaningful association with CAD risk.

Comparison of Strain in GaN-Based Blue Light-Emitting Diode Grown on Silicon(111) and Sapphire Substrates.

We compare the strain states and device performances of GaN-based blue light-emitting diodes (LEDs) grown on Si(111) and sapphire substrates. The strain characteristics are investigated using micro-Raman spectroscopy and high-resolution transmission electron microscopy. These analyses reveal that GaN layer grown on Si has a residual tensile strain in contrast to a compressive strain for GaN on sapphire, and quantum wells (QWs) on GaN/Si experience reduced lattice mismatch than those of GaN/sapphire. When external quantum efficiencies of LED on sapphire and Si substrates are compared, the LED on Si shows better efficiency droop characteristics and this is attributed to a decrease in piezo-electric field strength in InGaN/GaN layers owing to reduced lattice mismatch.

Berberine induces apoptosis via ROS generation in PANC-1 and MIA-PaCa2 pancreatic cell lines

Pancreatic cancer is the fourth leading cause of cancer death. Gemcitabine is widely used as a chemotherapeutic agent for the treatment of pancreatic cancer, but the prognosis is still poor. Berberine, an isoquinoline alkaloid extracted from a variety of natural herbs, possesses a variety of pharmacological properties including anticancer effects. In this study, we investigated the anticancer effects of berberine and compared its use with that of gemcitabine in the pancreatic cancer cell lines PANC-1 and MIA-PaCa2. Berberine inhibited cell growth in a dose-dependent manner by inducing cell cycle arrest and apoptosis. After berberine treatment, the G1 phase of PANC-1 cells increased by 10% compared to control cells, and the G1 phase of MIA-PaCa2 cells was increased by 2%. Whereas gemcitabine exerts antiproliferation effects through S-phase arrest, our results showed that berberine inhibited proliferation by inducing G1-phase arrest. Berberine-induced apoptosis of PANC-1 and MIA-PaCa2 cells increased by 7 and 2% compared to control cells, respectively. Notably, berberine had a greater apoptotic effect in PANC-1 cells than gemcitabine. Upon treatment of PANC-1 and MIA-PaCa2 with berberine at a half-maximal inhibitory concentration (IC50), apoptosis was induced by a mechanism that involved the production of reactive oxygen species (ROS) rather than caspase 3/7 activation. Our findings showed that berberine had anti-cancer effects and may be an effective drug for pancreatic cancer chemotherapy.

Berberine induces apoptosis via ROS generation in PANC-1 and MIA-PaCa2 pancreatic cell lines.

Pancreatic cancer is the fourth leading cause of cancer death. Gemcitabine is widely used as a chemotherapeutic agent for the treatment of pancreatic cancer, but the prognosis is still poor. Berberine, an isoquinoline alkaloid extracted from a variety of natural herbs, possesses a variety of pharmacological properties including anticancer effects. In this study, we investigated the anticancer effects of berberine and compared its use with that of gemcitabine in the pancreatic cancer cell lines PANC-1 and MIA-PaCa2. Berberine inhibited cell growth in a dose-dependent manner by inducing cell cycle arrest and apoptosis. After berberine treatment, the G1 phase of PANC-1 cells increased by 10% compared to control cells, and the G1 phase of MIA-PaCa2 cells was increased by 2%. Whereas gemcitabine exerts antiproliferation effects through S-phase arrest, our results showed that berberine inhibited proliferation by inducing G1-phase arrest. Berberine-induced apoptosis of PANC-1 and MIA-PaCa2 cells increased by 7 and 2% compared to control cells, respectively. Notably, berberine had a greater apoptotic effect in PANC-1 cells than gemcitabine. Upon treatment of PANC-1 and MIA-PaCa2 with berberine at a half-maximal inhibitory concentration (IC50), apoptosis was induced by a mechanism that involved the production of reactive oxygen species (ROS) rather than caspase 3/7 activation. Our findings showed that berberine had anti-cancer effects and may be an effective drug for pancreatic cancer chemotherapy.

Berberine diminishes side population and down-regulates stem cell-associated genes in the pancreatic cancer cell lines PANC-1 and MIA PaCa-2.

Cancer stem cells play an important role in metastasis and the relapse of drug resistant cancers. Side-population (SP) cells are capable of effluxing Hoechst 33342 dye and are referred to as cancer stem cells. We investigated the effect of berberine on pancreatic cancer stem cells of PANC-1 and MIA PaCa-2. For both cell lines, the proportions of SP cells in the presence of berberine were investigated and compared to the proportions in the presence of gemcitabine, a standard pancreatic anti-cancer drug. The proportions of SP cells in the PANC-1 and MIA PaCa-2 cell lines were about 9 and <0.1%, respectively. After berberine and gemcitabine treatments, the SP cell proportion of PANC-1 decreased to 5.7 ± 2.0 and 6.8 ± 0.8%, respectively, which compares to the control proportion of (9.7 ± 1.7). After berberine and gemcitabine treatment of PANC-1, of the four stem cell-associated genes (SOX2, POU5F1, NANOG, and NOTCH1), all but NOTCH1 were down-regulated. Unfortunately, the effect of berberine and gemcitabine treatments on MIA PaCa-2 SP cells could not be clearly observed because SP cells represented only a very small proportion of MIA PaCa-2 cells. However, SOX2, POU5F1, and NANOG genes were shown to be effectively down-regulated in the MIA PaCa-2 cell line as a whole. Taken together, these results indicate that berberine is as effective at targeting pancreatic cancer cell lines as gemcitabine. Therefore, we believe that POU5F1, SOX2, and NANOG can serve as potential markers, and berberine may be an effective anti-cancer agent when targeting human pancreatic cancer cells and/or their cancer stem cells.

Clinical and angiographic features and stroke types in adult moyamoya disease.

BACKGROUND AND PURPOSE: This study was conducted to elucidate the association between clinical and angiographic characteristics and stroke types in adult Moyamoya disease that has been rarely evaluated. MATERIALS AND METHODS: We analyzed the clinical and radiologic data obtained from a retrospective adult Moyamoya disease cohort with acute strokes, which were classified into 7 categories: large-artery infarct, hemodynamic infarct, perforator infarct, deep intracerebral hemorrhage, lobar intracerebral hemorrhage, intraventricular hemorrhage, and SAH. With conventional angiography, which was performed in the hemispheres with acute strokes, the Suzuki angiographic stage, intracranial aneurysm, major artery occlusion, and collateral vessel development were confirmed within 1 month of stroke onset. RESULTS: This study included 79 patients with acute ischemic stroke and 96 patients with acute hemorrhagic stroke. The angiographic stage had a strong tendency to be more advanced in the hemorrhagic than the ischemic patients (P = .061). Intracranial aneurysms were more frequently found in the hemorrhagic than ischemic or control hemispheres (P = .002). Occlusions of the anterior cerebral artery and development of fetal-type posterior cerebral artery were more frequently observed in the hemorrhagic than the ischemic (P = .001 and .01, respectively) or control hemispheres (P = .011 and .013, respectively). MCA occlusion (P = .039) and collateral flow development, including the ethmoidal Moyamoya vessels (P = .036) and transdural anastomosis of the external carotid artery (P = .022), occurred more often in the hemorrhagic than the ischemic hemispheres. Anterior cerebral artery occlusion occurred more frequently in patients with deep intracerebral hemorrhage or intraventricular hemorrhage than with lobar intracerebral hemorrhage (P = .009). CONCLUSIONS: In adult Moyamoya disease, major artery occlusion and collateral compensation occurred more often in the hemorrhagic than in the ischemic hemispheres. Thus, anterior cerebral artery occlusion with or without MCA occlusion and intracranial aneurysms may be the main contributing factors to hemorrhagic stroke in adult patients with Moyamoya disease.

Reactive oxygen species-responsive miR-210 regulates proliferation and migration of adipose-derived stem cells via PTPN2.

Hypoxia enhances the proliferation and migration of adipose-derived stem cells (ASCs) via the generation of reactive oxygen species (ROS). Therefore, this study primarily investigated whether or not ROS generation could regulate microRNA-210 (miR-210) expression, and increase proliferation/migration of ASCs. In addition, we tried to identify the signaling pathways involved in miR-210 upregulation and the direct target genes of miR-210 that mediate these functions. Various sources of ROS generation such as hypoxia, antimycin, rotenone, and platelet-derived growth factor (PDGF)-BB upregulated miR-210 expression, and increased the proliferation/migration of ASCs. There is a positive feed-forward loop between ROS generation and miR-210, and miR-210 itself increases ROS generation by downregulation of iron-sulfur cluster scaffold homolog 2 (ISCU2). Although hypoxia-inducible factor-1α was not involved in miR-210 expression, pharmacological or small interfering RNA (siRNA)-driven inhibition of Akt and ERK1/2 molecules reduced miR-210 expression. Transfection of siRNAs of NF-κB and Elk1 also reduced miR-210 expression, indicating that these signaling pathways mediate miR-210 upregulation. Protein tyrosine phosphatase, non-receptor type 2 (PTPN2) was selected for miR-210 target gene, and it was downregulated by ROS generators or miR-210 mimic treatment. PTPN2 was first proven to be a direct miR-210 target in luciferase activity assay, and pharmacological inhibition or overexpression of PTPN2 regulated the proliferation and migration of ASC. In conclusion, ROS generation from diverse sources induces miR-210 expression in ASCs via PDGFR-ß, Akt and ERK pathways. Transcription of miR-210 expression is regulated by NF-κB and Elk1, and miR-210 increases the proliferation and migration of ASCs via ISCU2 and PTPN2 downregulation.

The efficacy of endovascular treatment of ruptured blood blister-like aneurysms using stent-assisted coil embolization.

We report our experience with endovascular treatment and follow-up results of a ruptured blood blister-like aneurysm (BBA) in the supraclinoid internal carotid artery. We performed a retrospective review of ruptured blood blister-like aneurysm patients over a 30-month period. Seven patients (men/women, 2/5; mean age, 45.6 years) with ruptured BBAs were included from two different institutions. The angiographic findings, treatment strategies, and the clinical (modified Rankin Scale) and angiographic outcomes were retrospectively analyzed. All seven BBAs were located in the supraclinoid internal carotid artery. Four of them were ≥ 3 mm in largest diameter. Primary stent-assisted coiling was performed in six out of seven patients, and double stenting was done in one patient. In four patients, the coiling was augmented by overlapping stent insertion. Two patients experienced early re-hemorrhage, including one major fatal SAH. Complementary treatment was required in two patients, including coil embolization and covered-stent placement, respectively. Six of the seven BBAs showed complete or progressive occlusion at the time of late angiographic follow-up. The clinical midterm outcome was good (mRS scores, 0 -1) in five patients. Stent-assisted coiling of a ruptured BBA is technically challenging but can be done with good midterm results. However, as early re-growth/re-rupture remains a problem, repeated, short-term angiographic follow-up is required so that additional treatment can be performed as needed.

Laser-driven proton acceleration enhancement by nanostructured foils.

Nanostructured thin plastic foils have been used to enhance the mechanism of laser-driven proton beam acceleration. In particular, the presence of a monolayer of polystyrene nanospheres on the target front side has drastically enhanced the absorption of the incident 100 TW laser beam, leading to a consequent increase in the maximum proton energy and beam charge. The cutoff energy increased by about 60% for the optimal spheres' diameter of 535 nm in comparison to the planar foil. The total number of protons with energies higher than 1 MeV was increased approximately 5 times. To our knowledge this is the first experimental demonstration of such advanced target geometry. Experimental results are interpreted and discussed by means of 2(1/2)-dimensional particle-in-cell simulations.

Epidermal regeneration by ent-16α, 17-dihydroxy-kauran-19-oic acid isolated from Siegesbeckia pubescens.

OBJECTIVES: Keratinocyte stem/progenitor cells (KSCs) are known to regenerate epidermal tissue which they perform through to their great regenerative capacity. MATERIALS AND METHODS: Because stimulation of resident KSCs may regenerate epidermal tissue, we devised a strategy to find an appropriate KSC activator from natural products and to develop it as a skin-rejuvenating agent. RESULTS: Ent-16α, 17-dihydroxy-kauran-19-oic acid (DHK) isolated from Siegesbeckia pubescens exhibited a KSC-stimulating effect during screening of natural products. DHK increased proliferation and migration of KSCs using the Akt/ERK pathway. We further examined the mechanism of KSC stimulation and found that phosphorylation of Y1068 epithelial growth factor receptor (EGFR) was significantly increased. Functional inhibition of EGFR using neutralizing antibody and a chemical inhibitor, AG1478, attenuated DHK-induced KSC stimulation. In a 3D culture model of KSCs, DHK treatment significantly induced establishment of fully stratified epidermis and increased numbers of p63-positive cells. Likewise, DHK treatment significantly accelerated healing of epidermal wounds created by laser and dermatome, and increased p63-positive cells, in animal models. CONCLUSION: Collectively, these results indicate that DHK regenerates epidermal tissue mainly through EGFR phosphorylation. As DHK has diverse advantages over recombinant growth factors for commercialization (that is long-term stability and skin permeability), DHK might be applied to wound-healing agents and to a basic materials used in cosmetics.

The effect of human fetal liver-derived mesenchymal stem cells on CD34+ hematopoietic stem cell repopulation in NOD/Shi-scid/IL-2Rã(null) mice.

Mesenchymal stem cells (MSCs) are progenitors that are capable of differentiating into mesenchymal tissues. They are known to support allogeneic hematopoietic stem cell transplantation by facilitating engraftment without increasing the risk of graft-versus-host disease. We optimized culture conditions for human fetal liver-derived MSCs (hFL-MSCs) to investigate the role of hFL-MSCs on repopulation of hematopoietic stem cells in NOD/Shi-scid/IL-2Rγ(null) (NOG) mice using CD34(+) hematopoietic stem cells (HSCs) derived from umbilical cord blood (UCB). FL-MSCs and CD34(+) HSCs were prepared from fetal liver and UCB, respectively. Twenty-four hours after irradiation, CD34(+) HSCs and hFL-MSCs were injected intravenously and intratibially into NOG mice. During 24 weeks posttransplantation, engraftment levels of human cells were analyzed in bone marrow, peripheral blood, and spleen of transplanted mice by flow cytometry. hFL-MSCs showed a fibroblast-like morphology and immunophenotypic characteristics appropriate for MSCs. hFL-MSCs prolonged the survival of NOG mice that had been cotransplanted with UCB CD34(+) cells. Fluorescence-activated cell-sorting analysis showed that engraftment of human cells was increased by cotransplantation of hFL-MSCs. However, significant enhancement of human cell engraftment was not detected in NOG mice regardless of the number of cotransplanted MSCs. Although survival of repopulating NOG mice and engraftment of human cells were prolonged by cotransplantation of hFL-MSCs, 8.0 × 10(6) MSCs were not sufficient to increase HSC engraftment in irradiated NOG mice in vivo.

Proteomic identification of proteins differentially expressed by nicotinamide in focal cerebral ischemic injury.

Nicotinamide exerts a potent neuroprotective effect against ischemia-induced brain injury. We identified proteins that were differentially expressed by nicotinamide treatment in ischemic brain injury. Focal cerebral ischemia was induced by middle cerebral artery occlusion (MCAO). Adult male Sprague-Dawley rats were treated with vehicle or nicotinamide (500 mg/kg) 2 h after the onset of MCAO. Brains were collected 24 h after MCAO and cerebral cortex regions were isolated. Protein spots with different intensities between vehicle- and nicotinamide-treated groups were detected using two-dimensional gel electrophoresis and identified by mass spectrometry. Among these proteins, γ-enolase, protein phosphatase 2A (PP2A) subunit B, and peroxiredoxin-2 (Prx-2) were significantly decreased in the vehicle-treated group compared to the nicotinamide-treated group. These identified proteins mediate cell differentiation and stabilization, and play a role as antioxidant enzymes. In contrast, 60 kDa heat shock protein (Hsp 60) was significantly increased in vehicle-treated animals, while nicotinamide prevented the injury-induced increase of this protein. These results suggest that nicotinamide mediates neuroprotective effects by up- and down-regulation of various specific proteins.

Intravenous Glycoprotein IIb/IIIa Inhibitor (Tirofiban) Followed by Low-Dose Intra-Arterial Urokinase and Mechanical Thrombolysis for the Treatment of Acute Stroke.

We investigated the efficacy and safety of the combined use of IV tirofiban and IA urokinase and/or mechanical thrombolysis for treating acute stroke patients. Thirteen, consecutive patients treated with IV tirofiban and IA thrombolysis with mechanical and/or local IA urokinase infusion were evaluated retrospectively. The amount of time before the beginning of treatment, urokinase dose, recanalization rates, and symptomatic hemorrhage were analyzed. Clinical outcome measures were assessed on admission, at discharge (National Institute of Health Stroke scale [NIHSS]), and three months after the end of their treatment (modified Rankin Scale scores [mRS]). There were 11 patients with internal carotid or middle cerebral artery occlusion treated within six hours of the onset of symptoms and two patients with basilar artery occlusion treated within 12 hours of their symptom onset. The median NIHSS score on admission was 18. The median amount of time from symptom onset to IV tirofiban infusion was 135 minutes, and the median time from symptom onset to IA therapy was 180 minutes. The median dose of urokinase was 200,000 U. Recanalization (thrombolysis in myocardial infarction grade 2 or 3) was achieved in 11 patients. No procedure-related complications were observed. There was one symptomatic hemorrhage. At discharge, the mean NIHSS score was 6.6 (range, 0-15). Overall, at the time of the three-month follow-up the functional outcome was favorable (modified Rankin Scale score 0-2) in eight out of 13 (62%) patients. Death at 90 days occurred in two of the 13 (15%) patients. Combined IV tirofiban and IA thrombolysis with mechanical clot disruption seems to be a feasible treatment in acute stroke and may be successful in re-establishing vessel patency and result in a good functional outcome in patients with major cerebral arteries occlusions.

Liquid chromatography-tandem mass spectrometry determination of N-nitrosamines released from rubber or elastomer teats and soothers.

A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method as an alternative to a gas chromatography-thermal energy analyser (GC-TEA) method recommended by the European Committee on Standardization (CEN) was validated for the simultaneous determination of eight N-nitrosamines released into artificial saliva from rubber or elastomer teats and soothers. N-nitroso-dipropylamine-d14 (NDPA-d14) was used as internal standard for accurate quantification. The method was validated with relatively good analytical results, including sufficiently low limits of detection (0.1-2 µg kg⁻¹) of sample) and good linearity (r²> 0.99) throughout the studied concentration ranges. Intra- and inter-day precisions expressed with the relative standard deviation (RSD, %) were 3.4-8.0% and 4.4-11.3%, which were below the performance criteria based on one-half of the value derived from the Horwitz value. It was also found that the LC-MS/MS method is sufficiently rugged and successfully applicable to its routine analysis for the compliance test of Commission Directive 93/11/EEC.

Ion spectrometer composed of time-of-flight and Thomson parabola spectrometers for simultaneous characterization of laser-driven ions.

An ion spectrometer, composed of a time-of-flight spectrometer (TOFS) and a Thomson parabola spectrometer (TPS), has been developed to measure energy spectra and to analyze species of laser-driven ions. Two spectrometers can be operated simultaneously, thereby facilitate to compare the independently measured data and to combine advantages of each spectrometer. Real-time and shot-to-shot characterizations have been possible with the TOFS, and species of ions can be analyzed with the TPS. The two spectrometers show very good agreement of maximum proton energy even for a single laser shot. The composite ion spectrometer can provide two complementary spectra measured by TOFS with a large solid angle and TPS with a small one for the same ion source, which are useful to estimate precise total ion number and to investigate fine structure of energy spectrum at high energy depending on the detection position and solid angle. Advantage and comparison to other online measurement system, such as the TPS equipped with microchannel plate, are discussed in terms of overlay of ion species, high-repetition rate operation, detection solid angle, and detector characteristics of imaging plate.

Isolation and characterization of mouse mesenchymal stem cells.

OBJECTIVE: Mesenchymal stem cells (MSCs) have been studied in regenerative medicine because of their unique immunologic characteristics. However, before clinical application in humans, animal models are needed to confirm their safety and efficacy. To date, appropriate methods and sources to obtain mouse MSCs have not been identified. Therefore, we investigated MSCs isolated from 3 strains of mice and 3 sources for the development of MSCs in a mouse model. MATERIALS AND METHODS: Male BALB/c, C3H and C57BL/6 mice were used to isolate MSCs from various tissues including bone marrow (BM), compact bone, and adipose tissue. The MSCs were maintained in StemXVivo medium. Immunophenotypes of the MSCs were analyzed by FACS and their growth potential estimated by the number of colony-forming unit fibroblasts. RESULTS: All MSCs that were isolated from BM, compact bone, and adipose tissue showed plastic-adherent, fibroblastic-like morphologic characteristics regardless of the mouse strain or cell source. However, culture of BM MSCs was less successful than the other tissue types. The FACS phenotype analysis revealed that the MSCs were positive for CD29, CD44, CD105, and Sca-1, but negative for CD34, TER-119, CD45, and CD11b. According to the results of the characterization, the adipose tissue MSCs showed higher growth potential than did other MSCs. CONCLUSION: The results of this study showed that culture of adipose tissue and compact bone-MSCs was easier than BM MSCs. Based on the results of immunophenotype and growth potential, C57BL/6 AT-MSCs might be a suitable source to establish a mouse model of MSCs.