We describe a new method for photorefractive response time measurement in fast photorefractive crystals based on continuous phase modulation in two-wave mixing. We report experimental results for undoped semi-insulating GaAs that are in good agreement with theory. Values obtained for the response time and photoelectron generation quantum efficiency are consistent with previously published data.

Mesenchymal stem cell (MSC)-based cell therapy has shifted into clinical trials to repair the damage of various tissues. In this setting, the survival of the transplanted cells contributes critically to the therapeutic effectiveness. To investigate the in vivo tracing of MSCs, a recombinant retroviral vector carrying firefly-luciferase reporter gene [pL (FLUC) SN] was constructed and several GPE + 86 cell clones that stably expressed fluc were selected. The retroviral supernatants were collected and used to transfect MSC derived from C57 mice. The cells were then screened with G418 and the expression of the exogenous gene was identified by luciferase enzyme activity analysis. Labeled mouse MSCs (2 x 10(6)) were injected into skeletal muscles, and the in situ expression was noninvasively tracked by in vivo bioluminescence imaging for 1, 3 and 6 days after transplantation. The results showed that the survival rates of the grafted cells dropped sharply with time, they were 57.2 +/- 11.7%, 8.6 +/- 2.5% and 5.4 +/- 3.1% on day1, 3 and 6 after transplantation, and no fluorescent signals above background were detected on day 10. It is concluded that the method described above could be used for in vivo tracing of grafted cells. Furthermore, MSCs could not survive even transplanted into the none-ischemic skeletal muscles.

In the present paper a method for the determination of strontium, barium, calcium, magnesium, silicon, iron, aluminum and sulfur in the product of strontium carbonate by X-ray fluorescence spectrometry with pressed powder sample preparation was developed, and the standard samples were synthesized by high purity reagent. As the contents of strontium in the product of strontium carbonate were very high, the phenomenon of spectrum-peak-saturated occurred and the count rate was overflowed according to the measuring condition which was automatically given by the software system of X-ray fluorescence spectrometry. As a result, the deviation of the measurement is greater. According to analyzing the measuring condition of strontium, a method was given for reducing the count rate by reducing the measuring power of strontium, thus achieving the goal of measurement. When sulfate was measured with pressed powder sample, the results were enhanced with the increase in measuring number. In light of this situation, a method was proposed to solve the problem. As the self-forming characteristic of the product of strontium carbonate was not so well, it was very difficult to press the sample successfully. So, the condition of squash method involving the kinds of the adhesives, the mixing technique with powder sample and the pressing-time technique was discussed. During making the sample, it was found that the effects of pellet formation were better if the time could be delayed by 120 seconds. Matrix effect was corrected by alpha coefficient method, the accuracy of the method was evaluated by analysis of synthetic sample. Detection limits of 0.623-107.6 mg x g(-1) were obtained. The results were in good agreement with certified values with precision of < 2.5% RSD.

We report the self-pumped phase conjugation of an 18 degrees -cut Ce-doped (K(y)Na(1-y))(2m)(Sr(x)Ba(1-x))(1-m) Nb(2)O(6) crystal at a 632.8-nm He-Ne laser wavelength. A maximum phase-conjugation reflectivity of 84.3% has been measured. In addition, its incident angular response and time response are measured.

Gap junctions play important roles in auditory function and skin biology; mutations in the Cx26 gene are the predominant cause of inherited nonsyndromic deafness and cause disfiguring skin disorders. Mass spectrometry was used to identify posttranslational modifications (PTMs) of Cx26 and determine whether they occur at sites of disease-causing mutations. Cx26 was isolated from transfected HeLa cells by sequential immunoaffinity and metal chelate chromatography using a tandem carboxyl-terminal hemagglutinin epitope and hexa(histidine-asparagine) sequence. In-gel and in-solution enzymatic digestions were carried out in parallel with trypsin, chymotrypsin and endoproteinase-GluC. Peptides were fractionated using reversed-phase matrix by stepwise elution with increasing concentrations of organic solvent. To improve detection of low abundance peptides and maximize sequence coverage, MALDI-TOF-MS (MS) and MALDI-TOF/TOF-MS/MS (MS/MS) spectra were acquired from each elution step using an Applied Biosystems 4800 tandem mass spectrometer. Acquisition, processing and interpretation parameters were optimized to improve ionization and fragmentation of hydrophobic peptides. MS and MS/MS coverage of Cx26 was significantly above that reported for other membrane proteins; 71.3% by MS, with 29.9% by MS/MS. MS coverage was 92.6% if peptides resulting from in-source collisions and/or partial enzymatic cleavages were considered. A variety of putative PTMs of Cx26 were identified, including acetylation, hydroxylation, gamma-carboxylation, methylation and phosphorylation, some of which are at sites of deafness-causing mutation. Knowledge of the PTMs of Cx26 will be instrumental in understanding how alterations in cellular mechanisms of Cx26 channel biogenesis and function lead to losses in auditory function and disfiguring skin disorders.

In the present study, we investigate the effect of wall flexibility on the plug propagation and the resulting wall stresses in small airway models with experimental measurements and numerical simulations. Experimentally, a flexible microchannel was fabricated to mimic the flexible small airways using soft lithography. Liquid plugs were generated and propagated through the microchannels. The local wall deformation is observed instantaneously during plug propagation with the maximum increasing with plug speed. The pressure drop across the plug is measured and observed to increase with plug speed, and is slightly smaller in a flexible channel compared to that in a rigid channel. A computational model is then presented to model the steady plug propagation through a flexible channel corresponding to the middle plane in the experimental device. The results show qualitative agreements with experiments on wall shapes and pressure drops and the discrepancies bring up interesting questions on current field of modeling. The flexible wall deforms inward near the plug core region, the deformation and pressure drop across the plug increase with the plug speed. The wall deformation and resulting stresses vary with different longitudinal tensions, i.e., for large wall longitudinal tension, the wall deforms slightly, which causes decreased fluid stress and stress gradients on the flexible wall comparing to that on rigid walls; however, the wall stress gradients are found to be much larger on highly deformable walls with small longitudinal tensions. Therefore, in diseases such as emphysema, with more deformable airways, there is a high possibility of induced injuries on lining cells along the airways because of larger wall stresses and stress gradients.

OBJECTIVE: To investigate the influence factors on survival and outcome of acute myeloid leukemia (AML) patients with t(8;21). METHODS: Eighty seven AML patients with t(8;21) after long-term follow-up were enrolled in the analysis of clinical feature, immunophenotype, chromosome karyotype, treatment regimen, as well as the overall survival (OS) and relapse-free survival (RFS). RESULTS: The overall complete remssion (CR) rate was 95.3%. CR rate after first course therapy was 69.8%, after first course therapy containing medium dose Ara-C was 86.2%, and after first course of therapy containing standard-dose Ara-C was 60.3%. The median OS duration was 16.4 months, median RFS 11.7 months, 3 year OS rate 42%, 5 year OS rate 39%, 3 year RFS rate 55% and 5 year RFS rate 55%. Male gender chromsome 9q(-) had statistical significance for shorter OS and poor outcome, 2 courses of post-remission therapy with intermediate dose Ara-C, induction theray with intermediate-dose Ara-C and post-remission with 4 courses consolidation therapy had statistically longer OS and RFS. CONCLUSION: Sex, chromosome karyotype, induction and consolidation therapy were important influence factors on OS and RFS. Application of intermediate dose Ara-C to induction and consolidation therapy leads to a higher CR rate, prolong OS and RFS.

ABSTRACT: BACKGROUND: Abnormal activation of protease activities during experimental autoimmune encephalomyelitis (EAE) in rats, a rodent model of multiple sclerosis, have been implicated in either the direct destruction of myelin components or the intracellular signal transduction pathways that lead to lymphocyte infiltration, oligodendrocyte destruction, neuronal dysfunctions and axonal degeneration. The identification of changes in regulated proteolytic events during EAE is crucial to uncover activated proteases that may underline the pathological features such as inflammation and demyelination. We looked for either non-tryptic or semi-tryptic peptides from a previous shotgun proteomics study using isobaric tags for relative and absolute quantification (iTRAQ) to compare the proteomes of normal and EAE rat lumbar spinal cords. RESULTS: In doing so, we discovered that several proteins such as alpha1-macroglobulin, a protease inhibitor, alpha1B-glycoprotein, beta2-microglobulin and sulfated glycoprotein 1 had non-tryptic peptide iTRAQ ratios that were significantly larger than the overall protein iTRAQ ratios, suggesting that such peptides may be markers for the proteolytic products generated by the protease(s) activated during EAE. Indeed, subsequent western blot analysis confirmed the dysregulation of specific protein cleavages in EAE tissues. Additional proteolytic changes in important CNS proteins such as neurofilament light polypeptide, phosphoglucomutase-1 were also observed. CONCLUSIONS: The results from this study revealed changes among both neuronal protein processing and endogenous proteolysis modulators in EAE animals. This information may provide a rationale for protease inhibitor-based therapeutic interventions for demyelinating diseases and multiple sclerosis.

OBJECTIVE: To evaluate the impact of the percentage of residual blasts in bone marrow at the end of induction chemotherapy (T1) or during myelosuppression phase (T2) on prognosis of de novo acute myeloid leukemia (AML)(non M(3)) in 105 cases. To refine AML risk-stratification by combining the percentage of residual blast cells (T1 or/and T2) with cytogenetic data based the South West Oncology Group (SWOG) criteria. METHODS: The data of 105 de novo AML (non M(3)) patients hospitalized between January 1st 1999 and February 1st 2008 were retrospectively reviewed. Results were analyzed with SPSS15.0 software. RESULTS:(1) Patients were divided into two subgroups by a cutoff of 5% residual bone marrow blasts at T1 or T2 time point. Patients with percentage of residual bone marrow blast cells < 5% had better complete remission (CR) rate, relapse-free survival (RFS) and overall survival (OS) than the patients with percentage > or = 5% at T1 or T2. The percentage of residual bone marrow blast cells at T1 was correlated with that at T2.(2) The prognosis of patients with intermediate karyotypes with percentage < 5% at T1 or T2 was similar to that of the patients with favorable karyotypes. The patients with intermediate karyotypes and percentage of residual bone marrow blasts > or = 5% at T1 or T2 are defined as a subgroup with prognosis similar to that of patients with unfavorable karyotypes.(3) COX regression analysis showed that the percentage of residual bone marrow blasts at T1 or T2 is an independent prognostic factor of AML. The percentage of residual bone marrow blasts at T1 may be more helpful in prognostication than that at T2. CONCLUSION: AML patients with percentage of residual bone marrow blasts < 5% after induction chemotherapy (T1 or T2) have better CR rate, RFS, OS than the patients with percentage > or = 5% at the same time point. Combination of cytogenetics and percentage of residual bone marrow blasts at T1 or T2 is helpful to divide patients with intermediate karyotypes into two subgroups with different prognosis. Thus, a better decision of treatment strategy can be designed.