Single crystal inelastic neutron scattering is used to study spin-wave excitations in the fully polarized state of the frustrated quantum ferroantiferromagnet BaCdVO (PO4)2. The data analysis is ...based on a Heisenberg spin Hamiltonian that includes as many distinct nearest-neighbor and next-nearest-neighbor interactions as allowed by crystal symmetry. All eight such exchange constants are obtained in a simultaneous fit to over 150 scans across the dispersion manifold. This establishes a definitive quantitative model of this material. It turns out to be substantially different from the one assumed in numerous previous studies based on powder experiments.
Background
Biliary atresia is a rare paediatric biliary obliteration disease with unknown aetiology, and is the most common indication for paediatric liver transplantation (LT). However, no consensus ...for predicting Kasai portoenterostomy (KP) outcomes using liver histological findings exists. Ki67 is a popular biomarker for measuring and monitoring cellular proliferation.
Methods
Ki67 (clone, MIB‐1) liver parenchyma expression was measured by immunohistochemical staining of samples from living donors and patients with biliary atresia to assess its value in predicting outcomes after
KP.
Results
Of 35 children with biliary atresia, 13 were native liver survivors (NLS), 17 were non‐NLS, and five had primary LT. The median proportion of Ki67 immunostained areas in donors and patients with biliary atresia at KP was 0·06 and 0·99 per cent respectively. Univariable analysis identified a high proportion of Ki67 areas, high Ki67 cell numbers and high Ki67‐positive/leucocyte common antigen‐positive cell numbers at KP as significant predictors of poor native liver survival after KP (hazard ratio 9·29, 3·37 and 12·17 respectively). The proportion of Ki67 areas in the non‐NLS group was significantly higher than that in the NLS group (1·29 versus 0·72 per cent respectively; P = 0·001), and then decreased at LT (0·32 per cent versus 1·29 per cent at KP; P < 0·001).
Conclusion
This study has demonstrated the clinical data and time course of Ki67 expression in patients with biliary atresia. High Ki67 expression at KP may be an important predictor of native liver survival following the procedure.
Antecedentes
La atresia biliar (biliary atresia, BA) es una enfermedad pediátrica rara que consiste en una obstrucción biliar de etiología desconocida, y es la indicación pediátrica más frecuente de trasplante hepático (liver transplantation, LT). Sin embargo, no existe consenso para predecir los resultados de la portoenterostomía de Kasai (Kasai portoenterostomy, KP) en base a los hallazgos histológicos hepáticos. El Ki67 es un biomarcador conocido para medir y controlar la proliferación celular.
Métodos
Se midieron los niveles de expresión del parénquima hepático de Ki67 (clon, MIB‐1) por tinción inmunohistoquímica de las muestras de cinco donantes vivos y 35 pacientes con BA, para evaluar su valor predictivo de los resultados de la KP.
Resultados
Los pacientes con BA incluían 13 sobrevivientes con hígado nativo (native liver survivors, NLS), 17 no NLS y 5 pacientes que se sometieron inicialmente a LT. La proporción media de las áreas de expresión de Ki67 en donantes y pacientes con BA en KP fue de 0,06% y 0,99%, respectivamente. El análisis univariado identificó una alta proporción de áreas de Ki67, un alto número de células Ki67, un alto número de células Ki67 positivas (+)/leucocitos (LCA/CD45) + en KP como predictores significativos de una peor supervivencia del hígado nativo después de KP (cociente de riesgos instantáneos, hazard ratio, HR 9,29, 3,37 y 12,17, respectivamente). La proporción de las áreas Ki67 fueron significativamente superiores en los pacientes sin NLS que en los pacientes con NLS (P = 0,001). Entre los pacientes sin hígado nativo, los niveles de Ki67 disminuyeron posteriormente de acuerdo con la presencia de una lesión hepática irreparable, tales como son los hígados con BA en LT (en KP versus en LT = 1,29% versus 0.32%; P < 0,001).
Conclusión
Demostramos los datos clínicos y la evolución temporal de la expresión de Ki67 en los pacientes con BA. El alto nivel de expresión de Ki67 en KP puede ser un predictor importante para la supervivencia del hígado nativo después de KP.
No consensus exists for predicting outcomes after Kasai portoenterostomy (KP) using liver histological findings. Ki67 (clone, MIB‐1) expression in liver parenchyma was measured by means of immunohistochemical staining of samples from five living donors and 35 patients with biliary atresia to assess its value in predicting KP outcomes. Univariable analysis identified high expression of Ki67 at the time of KP as a significant predictor of poor native liver survival after the procedure.
Ki67 a potential marker for liver survival after Kasai portoenterostomy
Little research has been conducted into hypoesthesia, and no studies have elucidated the risk factors for refractory hypoesthesia and compared treatment modalities. The purpose of this multicentre ...retrospective cohort study was to investigate the relationships between various risk factors, treatment modalities, and refractory hypoesthesia. Risk factors for refractory hypoesthesia after oral surgery were evaluated using univariate and multivariate analysis. To minimize the selection bias associated with a retrospective data analysis, a propensity score analysis was performed between the medication and non-medication groups (65 sites in each group). Moderate or severe hypoesthesia (odds ratio 13.42) and no or late administration of ATP/vitamin B12 (odds ratio 2.28) were significantly associated with refractory hypoesthesia. In the propensity score analysis, the incidence rate of refractory hypoesthesia in the medication group was lower than that in the non-medication group (P<0.001). This study demonstrated the multivariate relationships between various risk factors, treatment modalities, and refractory hypoesthesia. Moderate or severe hypoesthesia and no or late administration of ATP/vitamin B12 were significantly associated with refractory hypoesthesia. Therefore, clinicians should consider these risk factors and initiate early oral administration of ATP/vitamin B12 in cases of hypoesthesia.
Magnetic-field-induced phase transitions are investigated in the frustrated gapped quantum paramagnet Rb_{2}Cu_{2}Mo_{3}O_{12} through dielectric and calorimetric measurements on single-crystal ...samples. It is clarified that the previously reported dielectric anomaly at 8 K in powder samples is not due to a chiral spin liquid state as has been suggested, but rather to a tiny amount of a ferroelectric impurity phase. Two field-induced quantum phase transitions between paraelectric and paramagnetic and ferroelectric and magnetically ordered states are clearly observed. It is shown that the electric polarization is a secondary order parameter at the lower-field (gap closure) quantum critical point but a primary one at the saturation transition. Having clearly identified the magnetic Bose-Einstein condensation (BEC) nature of the latter, we use the dielectric channel to directly measure the critical divergence of BEC susceptibility. The observed power-law behavior is in very good agreement with theoretical expectations for three-dimensional BEC. Finally, dielectric data reveal magnetic presaturation phases in this compound that may feature exotic order with unconventional broken symmetries.
We performed inelastic neutron scattering experiments on a multiferroic material NdFe3(BO3)4 to explore the crystal field excitations, where the magnetic anisotropy of the Nd3+ crystal field was ...responsible for the multiferroicity. Flat modes were observed at 8.5 meV and 17.4 meV in the neutron spectrum. The analysis revealed that these excitations were the transitions from the ground state to the first and second excited states of the Nd3+ crystal field.
The isostructural series of S=1 quantum magnets Cs1−xRbxFeCl3 is investigated, using both thermodynamic measurements and inelastic neutron scattering experiments. It is found that with increasing Rb ...content the system evolves from the gapped state at x=0, through a quantum phase transition at x∼0.35, and to the magnetically ordered state at larger x. Inelastic neutron experiments for x=0, x=0.3, and x=1 demonstrate that the magnetic anisotropy and spin interactions are continuously tuned by the chemical composition. For the intermediate concentration all magnetic excitations are substantially broadened suggesting that disorder plays a key role in this species. For the two end compounds, excitations remain sharp.
Systematic analyses of interannual and seasonal variations of tropospheric NO2 vertical column densities (VCDs) based on GOME satellite data and the regional scale chemical transport model (CTM), ...Community Multi-scale Air Quality (CMAQ), are presented for the atmosphere over eastern Asia between 1996 and June 2003. A newly developed year-by-year emission inventory (REAS) was used in CMAQ. The horizontal distribution of annual averaged GOME NO2 VCDs generally agrees well with the CMAQ results. However, CMAQ/REAS results underestimate the GOME retrievals with factors of 2?4 over polluted industrial regions such as Central East China (CEC), a major part of Korea, Hong Kong, and central and western Japan. The most probable reasons for the underestimation typically over the CEC are accuracy of the basic energy statistic data, emission factors, and socio-economic data used for construction of emission inventory. For the Japan region, GOME and CMAQ NO2 data show reasonable agreement with respect to interannual variation and show no clear increasing trend. For CEC, GOME and CMAQ NO2 data indicate a very rapid increasing trend from 2000. Analyses of the seasonal cycle of NO2 VCDs show that GOME data have larger dips than CMAQ NO2 during February?April and September?November. Sensitivity experiments with fixed emission intensity reveal that the detection of emission trends from satellite in fall or winter has a larger error caused by the variability of meteorology. Examination during summer time and annual averaged NO2 VCDs are robust with respect to variability of meteorology and are therefore more suitable for analyses of emission trends. Analysis of recent trends of annual emissions in China shows that the increasing trends of 1996?1998 and 2000?2002 for GOME and CMAQ/REAS show good agreement, but the rate of increase by GOME is approximately 10?11% yr?1 after 2000; it is slightly steeper than CMAQ/REAS (8?9% yr?1). The greatest difference was apparent between the years 1998 and 2000: CMAQ/REAS only shows a few percentage points of increase, whereas GOME gives a greater than 8% yr?1 increase. The exact reason remains unclear, but the most likely explanation is that the emission trend based on the Chinese emission related statistics underestimates the rapid growth of emissions.
A single-crystal sample of the frustrated quasi-one-dimensional quantum magnet Cs2Cu2Mo3O12 is investigated by magnetic and thermodynamic measurements. A combination of specific heat and magnetic ...torque measurements maps out the entire H−T phase diagram for three orientations. Remarkably, a new phase emerges below the saturation field, irrespective of the crystal orientation. It is suggested that the presaturation phase represents spin-nematic order or other multimagnon condensate. The phase diagrams within the long-range-ordered dome are qualitatively different for each geometry. In particular, multiple transitions are identified in the field along the chain direction.
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