Field-induced Bose-Einstein condensation in zigzag spin chain KGaCu(PO4)2

Single crystals of GaKCu(PO4)2were synthesized using the hydrothermal method, and subsequent measurements of specific heat, magnetic susceptibility, and high-field magnetization were performed. A broad peak is observed in the magnetic susceptibility and specific heat curves, with the maximum values appearing at about 11.5 K and 5.29 K, respectively. The highest maximum peak value of susceptibility is observed when the magnetic field is applied along thec-axis, followed by thea-axis,b-axis, and polycrystalline samples. These indicate that the system exhibits one-dimensional magnetism and the magnetic easy axis is thecaxis. The magnetization at 2 K reveals the occurrence of a field-induced Bose-Einstein condensation (BEC) phase within the magnetic field range of approximately 8-12 T. High-field magnetization up to 40 T indicates that the compound reaches magnetization saturation as the field exceedsHs= 12 T. Through systematic measurements, a field-temperature (H-T) phase diagram was constructed, and dome-like phase boundaries were observed. The findings suggest that GaKCu(PO4)2is a spin gap system and a promising candidate for studying BEC of magnons due to its phase transition boundary occurring at low magnetic fields.

[Clinical study on early predictors of concurrent bile duct injury following TACE in patients with liver cancer]

Objective: To explore the predictive factors of concurrent bile duct injury following transcatheter arterial chemoembolization (TACE) in patients with hepatocellular carcinoma (HCC). Methods: A retrospective study was conducted on 483 HCC patients in relation to TACE postoperative complications. A total of 21 cases of bile duct injury were observed following the TACE procedure. Laboratory data, imaging data, and clinically relevant medical histories were recorded before and after one week following the TACE procedure and follow-up. The χ (2) test, or Fisher's exact probability method, was used for categorical variables. The mean of the two samples was compared using a paired t-test or Wilcoxon rank sum test. The comparison of multiple mean values was conducted using an analysis of variance. Results: Twenty-one cases with bile duct injury had intrahepatic bile duct dilatation, bile tumors, hilar biliary duct stenoses, and other manifestations. 14.3% (3/21) of patients showed linear high-density shadows along the bile duct on a plain CT scan, while 76.2% (16/21) of patients had ALP > 200 U/L one week following TACE procedure, and bile duct injury occurred in later follow-up. Alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), and γ-glutamyl transferase (GGT) were significantly increased in all patients following TACE procedure (t = -2.721, P = 0.014; t = -2.674, P = 0.015; t = -3.079, P = 0.006; t = -3.377, P = 0.003, respectively). Conclusion: The deposition of iodized oil around the bile duct on plain CT scan presentation or the continuous increase of ALP (> 200 U/L) one week following TACE procedure has a certain predictive value for the later bile duct injury.

[Impact of sinonasal anatomic changes after endoscopic anterior skull base surgery on nasal airflow and air conditioning: a computational fluid dynamics study]

Objective: To analyze the impact of the sinonasal anatomic changes after endonasal endoscopic anterior skull base surgery on the nasal airflow and heating and humidification by computational fluid dynamics (CFD), and to explore the correlation between the postoperative CFD parameters and the subjective symptoms of the patients. Methods: The clinical data in the Rhinology Department of the First Affiliated Hospital of Zhengzhou University from 2016 to 2021 were retrospectively analyzed. The patients received the endoscopic resection of the anterior skull base tumor were selected as the case group, and the adults whose CT scans had no sinonasal abnormalities were chosen as the control group. The CFD simulation was performed on the sinonasal models after reconstructed from the patients' sinus CT images during the post-surgical follow-up. All the patients were asked to complete the Empty Nose Syndrome 6-Item Questionnaire (ENS6Q) to assess the subjective symptoms. The comparison between two independent groups and the correlation analysis were carried out by using the Mann-Whitney U test and the Spearman correlation test in the SPSS 26.0 software. Results: Nineteen patients (including 8 males and 11 females, from 22 to 67 years old) in the case group and 2 patients (a male of 38 years old and a female of 45 years old) in the control group were enrolled in this study. After the anterior skull base surgery, the high-speed airflow moved to the upper part of the nasal cavity, and the lowest temperature shifted upwards on the choana. Comparing with the control group, the ratio of nasal mucosal surface area to nasal ventilation volume in the case group decreased [0.41 (0.40, 0.41) mm^-1 vs 0.32 (0.30, 0.38) mm^-1; Z=-2.04, P=0.041], the air flow in the upper and middle part of the nasal cavity increased [61.14 (59.78, 62.51)% vs 78.07 (76.22, 94.43)%; Z=-2.28, P=0.023], the nasal resistance decreased [0.024 (0.022, 0.026) Pa·s/ml vs 0.016 (0.009, 0.018) Pa·s/ml; Z=-2.29, P=0.022], the lowest temperature in the middle of the nasal cavity decreased [28.29 (27.23, 29.35)℃ vs 25.06 (24.07, 25.50)℃; Z=-2.28, P=0.023], the nasal heating efficiency decreased [98.74 (97.95, 99.52)% vs 82.16 (80.24, 86.91)%; Z=-2.28, P=0.023], the lowest relative humidity decreased [(79.62 (76.55, 82.69)% vs 73.28 (71.27, 75.05)%; Z=-2.28, P=0.023], and the nasal humidification efficiency decreased [99.50 (97.69, 101.30)% vs 86.09 (79.33, 87.16)%; Z=-2.28, P=0.023]. The ENS6Q total scores of all patients in the case group were less than 11 points. There was a moderate negative correlation between the proportion of the inferior airflow in the post-surgical nasal cavity negatively and the ENS6Q total scores (r_s=-0.50, P=0.029). Conclusions: The sinonasal anatomic changes after the endoscopic anterior skull base surgery alter the nasal airflow patterns, reducing the efficiency of nasal heating and humidification. However, the post-surgical occurrence tendency of the empty nose syndrome is weak.

High-field magnetization and electronic spin resonance study in the twisted honeycomb latticeα-Mn2V2O7

We report the single-crystal growth of Mn₂V₂O₇and the results of magnetic susceptibility, high-field magnetization up to 55 T and high-frequency electric spin resonance (ESR) measurements for its low-temperatureαphase. Two antiferromagnetic (AFM) ordering at 17.5 K and 3 K and obvious magnetic anisotropy are observed inα-Mn₂V₂O₇upon cooling. In pulsed high magnetic fields, the compound reaches the saturation magnetic moment of ∼10.5μ_Bfor each molecular formula at around 45 T after two undergoing AFM phase transitions atH_c1≈ 16 T,H_c2≈ 34.5 T forH//[11-0] andH_sf1= 2.5 T,H_sf2= 7 T forH//[001]. In these two directions, two and seven resonance modes are detected by ESR spectroscopy, respectively. Theω₁andω₂modes ofH//[11-0] can be well described by two-sublattice AFM resonance mode with two zero-field gaps at 94.51 GHz and 169.28 GHz, indicating a hard-axis feature. The seven modes forH//[001] are partially separated by the critical fields ofH_sf1andH_sf2, displaying the two signs of spin-flop transition. The fittings ofω_c1andω_c2modes yield zero-field gaps at 69.50 GHz and 84.73 GHz forH//[001], confirming the axis-type anisotropy. The saturated moment and gyromagnetic ratio indicate the Mn²⁺ion inα-Mn₂V₂O₇is in a high spin state with orbital moment completely quenched. A quasi-one-dimensional magnetism with a zig-zag-chain spin configuration is suggested inα-Mn₂V₂O₇, due to the special neighbor interactions caused by a distorted network structure with honeycomb layer.

Interface effects of Schottky devices built from MoS2and high work function metals

Schottky junctions, formed by high work function metals and semiconductors, are important devices in electronics and optoelectronics. The metal deposition in traditional Schottky interfaces usually damages the semiconductor surface and causes defect states, which reduces the Schottky barrier height and device performance. This can be avoided in the atomically smooth interface formed by two-dimensional (2D) metals and semiconductors. For better interface tailoring engineering, it is particularly important to understand various interface effects in such 2D Schottky devices under critical or boundary conditions. Here we report the fabrication and testing of three types of MoS₂devices, i.e., using PtTe₂, Cr and Au as contact materials. While the Cr/MoS₂contact is an ohmic contact, the other two are Schottky contacts. The van-der-Waals interface of PtTe₂-MoS₂results in a well-defined OFF state and a significant rectification ratio of 10⁴. This parameter, together with an ideality factor 2.1, outperforms the device based on evaporated Au. Moreover, a device in the intermediate condition is also presented. An abrupt increase in the reverse current is observed and understood based on the enhanced tunneling current. Our work manifests the essential role of doping concentration and provides another example for 2D Schottky interface design.

[Multi-level scanning of environmental factors of body mass index of children and adolescents aged 7-17 years in China]

Objective: To investigate the influence of environmental factors on body mass index of children and adolescents in China. Methods: Using data from the China Health and Nutrition Survey, the research object to 7 - 17 years old children and adolescents who participated in 2000, 2006, 2011, and 2015 round of survey with complete data, a total of 6 626 children and adolescents (male 3 473, female 3 153) were investigated under univariate analysis for each environmental factor variable before using Partial Least Square Regression fitting a linear model for further screening. Finally, we fitted a three-level linear mixed-effects model distinct by urban and rural area for analysis. Results: The three-level null model, log likelihood=-17 034.68, χ²=483.06, P<0.001. Intern-class correlation coefficient (ICC) showed that community-level was 9.97%, and both community and individual were 39.38%. The three-level model also showed that urban model's urbanization index (β=-0.05, 95%CI: -0.09--0.01, P<0.05), the park location (β=-0.88, 95%CI: -1.72 - -0.04, P<0.05), 15 - 17 age group (β=-1.04, 95%CI:-1.78 - -0.30, P<0.05) were negatively correlated with BMI. The distance to the gym (β=0.12, 95%CI: 0.02 - 0.22, P<0.05), the number of home TV sets (β=0.50, 95%CI: 0.08 - 0.92, P<0.05) and the frequency of parents' alarm of fiction TV program contents (β=1.85, 95%CI: 0.70 - 3.00, P<0.05) were correlated with BMI. Rural urbanization index (β=-0.04, 95%CI:-0.07 - -0.01, P<0.05). Rural per capita income (β=-7.29e^-4, 95%CI:-1.00e^-3 - -6.77e^-5, P<0.05), parents' restricted frequency of watching TV (β=-1.29, 95%CI:-2.36 - -0.21, P<0.05), adipo-energy ratio (β=-0.03, 95%CI:-0.06 - -1.00e^-3, P<0.05) were negatively correlated with the BMI. Factors as the frequency of parents' alarm of fiction TV program contents (β=3.01, 95%CI: 0.03 - 6.00, P<0.05), the survey time was 2015 (β=4.83, 95%CI: 1.96 - 7.69, P<0.05) were correlated with BMI. Conclusions: Environmental factors could indirectly influence the change of BMI of children and adolescents to different degrees and various aspects. Urbanization index and rural per capita income had a slight protective effect on increasing BMI of children and adolescents. At the community level, attention should be paid to the setting of activity places around the living environment of children and adolescents. Family members should also guide their children and adolescents to develop nice behavior in watching TV.

Wide-spectrum photodetector constructed on a centimeter-scale flexible SnSe2film using a new one-step strategy

Two-dimensional (2D) materials attached with flexible substrates enable possibilities to apply their superior properties to the rapidly increasing demand for foldable displays and wearable biosensors in the internet-of-things technology. However, previous two-step strategy to construct the flexible devices, namely first obtaining 2D materials elsewhere and then transferring them onto flexible substrates, can cause huge problems, including irreversibly undermining the device performance and limiting the material size. Here we propose a new one-step strategy (other than the liquid phase processing and low temperature synthesis methods), namely directly depositing appropriate 2D materials onto flexible substrates, which involves no transferring and can maintain the crystal quality and properties to the greatest extent. More importantly, this strategy in principle has no limit in the film size, hence removing a main obstacle for the practical use of flexible films, such as complex logic operations and large-area optoelectronic applications. Using this strategy, a centimeter-scale SnSe₂film is directly grown on polydimethylsiloxane, which is characterized as a uniform, out-of-plane oriented and semiconducting film that is robust to deformations. Based on the film, a flexible photodetector is fabricated and distinct photoresponse to a broad spectrum of light (405-830 nm) is observed, with remarkable technical parameters.

MicroRNA-20a suppresses RANKL-modulated osteoclastogenesis and prevents bone erosion in mice with rheumatoid arthritis through the TLR4/p38 pathway

Abnormal osteoclast formation plays a significant part in rheumatoid arthritis (RA). As potent therapeutic biomarkers, microRNAs (miRNAs) have obtained increasing attention. Recently, treatment regimens regarding miRNAs have been implicated in skeletal diseases. The aim of this study is to assess the expression and function of miR-20a during osteoclast proliferation and differentiation and its correlation with bone erosion in RA mice. The expression of miR-20a was observed to be diminished in the ankle tissues of RA mice relative to that in normal controls evaluated by RT-qPCR. Hematoxylin and eosin staining, Safranin O-fast green staining, and tartrateresistant acid phosphatase staining were used to evaluate the effects of miR-20a on RA symptoms. The proliferation and differentiation of osteoclasts, and bone erosion were repressed by agomiR-20a injection. 3'UTR luciferase reporter assays were conducted to validate the putative binding between miR-20a and receptor activation of nuclear factor-κB ligand (RANKL). The protein expression and phosphorylation level of toll-like receptor4 (TLR4)/p38 pathway-related factors were detected by Western blot. miR-20a inhibited proliferation and differentiation potentials to osteoclasts partly through the TLR4/p38 pathway. The current work provides evidence that miR-20a hinders proliferation and differentiation of osteoclasts by targeting RANKL through the TLR4/p38 pathway.

[Level of serum uric acid and prevalence of hyperuricemia among Chinese adults aged 18-59 years old in 15 provinces, 2015]

Objective: To investigate the level of serum uric acid and the prevalence of hyperuricemia among adult residents in China. Methods: Data were derived from the China Nutritional Transition Cohort Study (CNTCS) in 2015. A total of 8 217 adult residents, aged 18-59 years old, who had completed survey data were selected as the subjects of the study. The demographic data was collected by questionnaire, and the fasting serum uric acid was detected by enzymatic method on the automatic biochemical analyzer (German Roche C701/702) by using German Roche uric acid reagent test kit. The levels of serum uric acid and the prevalence of hyperuricemia were analyzed under different demographic characteristics. Results: The results showed that, in 2015, the average level of serum uric acid in Chinese adults aged 18-59 years old was 288.0 μmol/L, and the prevalence rate of hyperuricemia was 9.8% (weighted value). Among them, the average level of serum uric acid and weighted prevalence of hyperuricemia was 329.7 μmol/L and 15.1% in men and 254.3 μmol/L and 5.8% in women. The average level of serum uric acid and weighted prevalence of hyperuricemia was 298.5 μmol/L and 10.9% in urban residents and 281.9 μmol/L and 9.1% in rural residents. The level of serum uric acid and the prevalence rate of hyperuricemia decreased when age increased in men, but increased with age increased in women. Conclusions: There are some differences in the level of serum uric acid and the prevalence rate of hyperuricemia among adult residents of different regions, gender, ages, household income and educational level. It is suggested that accurate prevention and control measures should be taken according to different demographic characteristics.

[Analysis of magnetic resonance imaging findings of fungal spondylitis]

The clinical and magnetic resonance imaging(MRI) data of 8 cases of fungal spondylitis were retrospectively enrolled in the study, and the typical MRI findings were mainly discussed. The results released that fungal spondylitis should be suspected when the infection spreads along paraspinal ligament, and vertebral lesions show jumping discontinuous distribution. A blurred and incomplete outline of endplate on T1 weighted imaging sequence, loss of hyperintensity of the vertebral body, and banded like hypointensity under endplate on T₂ weighted imaging sequence, indicate fungal spondylitis. These features contribute to the diagnosis and differential diagnosis of fungal spondylitis.

Effects of posthatch feed deprivation on residual yolk absorption, macronutrients synthesis, and organ development in broiler chicks

The aim of the research was to evaluate the dynamic changes of early posthatch starvation on residual yolk absorption, synthesis of macronutrients (protein, lipid, and glycogen), and organ development in broiler chicks. A total of 720 1-day-old chicks (Lingnan Yellow) were randomly assigned to 3 treatments: group A (nonfasted), group B (fasting for 24 h after placement), and group C (fasting for 48 h after placement). The trial lasted for 168 h, and water was provided ad libitum all the time. Sampling was performed at 0, 24, 48, 72, 120, and 168 h. Nonfasting (group A) promoted (P < 0.05) the absorption of amino acids, fatty acids, mineral elements, protein, and maternal antibody in the residual yolk of broiler chicks. The concentration of insulin-like growth factor 1 in plasma and the liver was higher (P < 0.05) in group A. Nonfasting enhanced (P < 0.05) the synthesis of protein and glycogen in the breast muscle and liver; the relative weights of the liver, pancreas, and spleen; and body weight, but retarded (P < 0.05) the synthesis of triglyceride in the liver. The results indicated that nonfasting (group A) after placement promoted the absorption of residual yolk and synthesis of protein and glycogen in the breast muscle and liver, whereas early feed deprivation promoted the synthesis of lipid in the liver. Thereby, nonfasting after placement promoted organ development and body growth of broiler chicks.

Inhibition of protein kinase C activity inhibits osteosarcoma metastasis

INTRODUCTION

For some cancers bone is the preferred site for metastasis and involves a cascade involving transition of epithelial cells to mesenchymal cells and subsequent intravasation to the blood and lymph vessels, and finally hematogenous dissemination to perivascular niches of the bone marrow sinusoids. It has been shown that protein kinase C can aid metastasis to bone. Hence, pharmacological inhibition of protein kinase C (PKC) activity is thought of as a potential therapeutic option in bone metastatic lesions. The objective of the current study was to investigate how PKCs exert their effect on bone cancer metastasis and to test the efficacy of pharmacological inhibition of PKC on bone metastasis.

MATERIAL AND METHODS

The effect of the PKC inhibitor Go6983 on epithelial and mesenchymal cell marker expression in the osteosarcoma cell line DAN was determined by immunoblot and immunofluorescence analysis. The in vivo effect of Go6983 was evaluated with a xenograft model using DAN cells.

RESULTS

Treatment with transforming growth factor β (TGF-β) led to loss of the epithelial cell marker and gain of mesenchymal cell markers in the osteosarcoma cell line, DAN. This transition occurred concomitantly with PKC activation. TGF-β-mediated PKC activation resulted in activation of ribosomal protein 6 (S6), but not S6K1. Pharmacological inhibition of PKC activation attenuated these effects. In a xenograft model of experimental metastasis, pharmacological inhibition of PKC activation over a period of 4 weeks reduced both tumor burden and metastasis to lungs.

CONCLUSIONS

Our results indicate that PKC potentiates tumor metastasis to the bone by potentiating translation increase and can be putatively inhibited by pharmacological inhibition.

[A new prognostic score system of hepatocellular carcinoma following hepatectomy]

Objective: To establish a new scoring system based on the clinicopathological features of hepatocellular carcinoma (HCC) to predict prognosis of patients who received hepatectomy. Methods: A total of 845 HCC patients who underwent hepatectomy from 1999 to 2010 at Cancer Hospital, Chinese Academy of Medical Sciences were retrospectively analyzed. 21 common clinical factors were selected in this analysis. Among these factors, the cut-off values of alpha-fetoprotein (AFP), alkaline phosphatase (ALP) and intraoperative blood loss were evaluated by using a receiver operating characteristic (ROC) curve analysis.The Kaplan-Meier method and Cox regression model were used to evaluate the independent risk factors associated with the prognosis of HCC patients after hepatectomy. HCC postoperatively prognostic scoring system was established according to the minimum weighted method of these independent risk factors, and divided the patients into 3 risk groups, including low-risk, intermediate-risk and high-risk group. The relapse-free survival (RFS) and overall survival (OS) were compared among these groups. Results: The univariate analysis showed that clinical symptoms, preoperative α-fetoprotein (AFP) level, serum alkaline phosphatase (ALP) level, tumor size, tumor number, abdominal lymph node metastasis, macrovascular invasion or tumor thrombus, extrahepatic invasion or serosa perforation, the severity of hepatic cirrhosis, intraoperative blood loss, the liver operative method, pathological tumor thrombus, intraoperative blood transfusion, perioperative blood transfusion were significantly associated with median RFS of these HCC patients (P<0.05). Alternatively, clinical symptoms, preoperative AFP level, serum ALP level, tumor size, tumor number, abdominal lymph node metastasis, macrovascular invasion or tumor thrombus, extrahepatic invasion or serosa perforation, the severity of hepatic cirrhosis, intraoperative blood loss, the liver operative method, pathological lymphocyte invasion, pathological tumor thrombus, intraoperative blood transfusion, perioperative blood transfusion were significantly associated with the median OS of these HCC patients (P<0.05). The multivariate analysis showed that AFP ≥20 ng/ml, clinical symptoms, tumor diameter ≥5 cm, multiple tumors, macrovascular invasion or tumor thrombus, extrahepatic invasion or serosa perforation, moderate and severe liver cirrhosis, non- anatomic resection were the independent risk factors of RFS and OS (P<0.05). The independent risk factor of RFS was intraoperative bleeding loss ≥325 ml (P<0.05); The independent risk factors of OS were abdominal lymph node metastasis and pathological tumors thrombus (P<0.05). The respective weight of 11 independent factors was used to establish the scoring system (scores range from 0 to 26). In the score system, 0 to 5 points were defined as the low-risk group (286 cases), 6 to 12 points were determined as the intermediate-risk group (503 cases), more than 13 points were classified as the high-risk group (56 cases). The median RFS of the low-risk, intermediate-risk and high-risk group were 80, 27 and 6 months, respectively. The differences were statistically significant (P<0.001). The median OS of the three groups were 134, 51 and 15 months, respectively, and the differences were statistically significant (P<0.001). Conclusion: This new score system provides effective prediction of postoperative prognosis for HCC patients.

[Analysis of clinical prognosis and the correlation between bile duct injury after transcatheter arterial chemoembolization and the level of hepatic arterial embolization in patients with hepatocellular carcinoma]

Objective: To evaluate the correlation between bile duct injury after transcatheter arterial chemoembolization and the level of hepatic arterial embolization, and to analyze the clinical prognosis of hepatocellular carcinoma patients. Methods: From January18, 2012 to December18, 2014, 21 patients underwent TACE for HCC were retrospectively reviewed, including patients' clinical and pathological data. The clinical outcome and relevant factors for bile duct injury were analyzed. Results: A total of 21 patients were identified with bile duct injury at our single institution. All patients received 48 TACE treatments, including proper hepatic artery (14), left hepatic artery (3), the right hepatic artery (10), left and right hepatic artery (9) and tumor artery branches (12). Thirty-five bile duct injury occurred in 21 patients: 7 cases was close to the tumor, 2 distant to the tumor, 7 at right liver, 2 left liver, 11 both lobes of liver and 6 hepatic hilar. After medical conservative treatment and biliary tract inside and outside drainage, liver function of 10 cases were improved. In four patients with hepatic bile duct stricture and biloma, the effect of drainage was not obvious, which subsequently caused biliary complications such as infection, gallbladder and common bile duct stones. Three patients with liver cirrhosis at decompensation stage developed complications, and one of them died of hepatic encephalopathy. Four patients experienced tumor recurrence during the follow-up period. Conclusions: The location of bile duct injury after transcatheter arterial chemoembolization is quite consistent with the level of hepatic arterial embolization. There may be some blood vessels mainly involved in blood supply of biliary duct. Complete embolism of these vessels may lead to bile duct injuries. Biliary drainage is ineffective in patients with hilar bile duct stricture, and can lead to complications of biliary tract later on.

[Application on the quantitative perfusion parameters of dynamic contrast-enhanced MRI in the pathological subtype of uterine leiomyoma]

Objective: To analyze the value of the quantitative perfusion parameters of dynamic contrast-enhanced MRI(DCE-MRI) in the pathological subtype of uterine leiomyoma. Methods: A total of 35 cases of uterine leiomyoma confirmed by surgery and pathology were retrospectively analyzed in Shaoxing People's Hospital from October 2015 to May 2016.All cases underwent DCE-MRI. Quantitative perfusion parameters were prospectively measured and analyzed, including transfer constant (K(trans)) , efflux rate constant (K(ep)), extravascular extracellular space volume ratio (V(e)), blood plasma volume ratio (V(p)), permeability surface area product (PS) and plasma flow (F(p)) , using signal-input two-compartment tracer kinetic models (Extended Tofts model and Exchange model) in 35 leiomyoma cases.After the operation, the 35 cases were divided into three groups according to the pathological classfication , the ordinary, the cellular and the degeneration type.To analyze the differences among the three groups about the quantitative perfusion parameters of uterine leiomyoma. Compared with the gold standard of pathological findings, the ROC curves were drawn to evaluate the diagnostic efficacy of different quantitative perfusion parameters. Results: In the ordinary, cellular and degeneration type of uterine leiomyoma, K(trans) value were respectively(0.684±0.341), (1.897±0.458), (0.554±0.514)/min; K(ep) were respectively(1.004±0.685), (2.362±1.001), (1.274±1.093)/min; V(e) were respectively 0.789%±0.186%, 0.806%±0.203%, 0.537%±0.314%; V(p) were respectively 0.145%±0.196%, 0.502%±0.338%, 0.062%±0.106% and F(p) were respectively(0.792±0.461), (2.426±0.509), (0.628±0.551)ml/min.Among three groups, the value of K(trans), K(ep), V(e), V(p) and F(p) had statistical difference(all P<0.05), the value of PS didn't have statistical difference. The value of K(trans), K(ep), V(p) and F(p) in cellular type were higher than the ordinary type(all P<0.01); the value of K(trans), V(p) and F(p) in cellular type were higher than the degeneration type(all P<0.01); the value of V(e) in ordinary type was higher than the degeneration type(P<0.05). The area under ROC curve was 0.981 for K(trans), 0.904 for K(ep), 0.622 for V(e), 0.840 for V(p) and 0.994 for F(p). Conclusion: The quantitative perfusion parameters of DCE-MRI , especially the value of K(trans), K(ep), V(p) and F(p) have a great diagnostic efficacy in the pathological classfication of uterine leiomyoma which will become a predictive factor of pathological classfication in uterine leiomyoma.

[Correlation between the CT features and malignancy risk of small (≤5 cm) gastric stromal tumors]

Objective: To evaluate the correlation between computed tomography (CT) features and malignancy risk category of small (≤5 cm) gastric stromal tumors (GST), in order to provide an image reference for preoperative assessment and intraoperative pathological diagnosis. Methods: Eighty-three patients with surgically and pathologically proven GST (≤5 cm) between January 2011 and November 2015 were recruited, and their clinical, pathological and CT data were retrospectively analyzed. According to the pathological results and malignancy risk category, the patients were divided into 2 groups, the benign biological behavior group (very low and low risk) and malignant biological behavior group (intermediate and high risk). The clinical, pathological and CT imaging findings of the two groups were analyzed. Based on the tumor diameter, the receiver operating characteristic curve (ROC) was applied to evaluate the sensitivity, specificity and the best cut-off point for distinguishing the malignancy risk between the two groups. Results: The lobulation and ulceration of the tumors presented statistically significant difference for the malignancy risk between the two groups (χ(2)=6.273 and 4.163, respectively; all P<0.05), but there was no significant difference in the sex, clinical symptoms, serum ferritin, tumor site, growth pattern, cystis degeneration and calcification (all P>0.05). No statistically significant differences were detected for the tumor CT value, arterial CT value, venous CT value, degrees of enhancement in arterial phase (DEAP), enhancement in portal venous phase (DEPP), and patient's age for distinguishing the malignancy risk between the two groups (all P>0.05). On the other hand, significant differences were found in the maximum diameter (Dmax) of tumor and the minimum diameter (Dmin) of tumor (t=-3.256 and -3.466, respectively; all P<0.05). When the cut-off point of Dmax was 1.6 cm, the area under the ROC curve, sensitivity and specificity were 0.704, 92.3% and 75.4%, respectively. When the cut-off point of Dmin was 1.5 cm, the area under the ROC curve, sensitivity and specificity were 0.713, 88.5% and 71.9%, respectively. Conclusion: CT features of the GST (≤5 cm) may predict, before surgery, the malignancy risk of small gastric stromal tumors, and provide the an image reference for preoperative assessment and intraoperative pathological diagnosis of the disease.

[Value of CT imaging in the differentiation of gastric leiomyomas from gastric stromal tumors]

Objective: To explore the application value of CT imaging in differentiating gastric stromal tumors (GST) from gastric leiomyomas (GLMs). Methods: CT images of patients with GST (n=65) or GLMs (n=13, maximum diameter of tumor ≤5 cm) proved by surgery and pathology were retrospectively analyzed. The tumor size, location, contour, growth pattern, degree and pattern of enhancement, calcification, necrosis, surface ulceration, lymph nodes, and patient clinical data were evaluated by two independent reviewers. Receiver operating characteristic (ROC) curves were employed to assess the measurement and calculation parameters in the differentiation of GST and GLMs. Results: Between the GST and GLMs groups, there was no statistically significant difference in the contour, growth pattern, calcification, surface ulceration, and patient's sex (P>0.05). CT values of in plain scans, degree of enhancement in arterial phase (DE1), size, location and pattern of enhancement were found to be different between GST and GLMs (P<0.05). When the cutoff value of the maximum tumor diameter was 3.2 cm, the area under ROC curve, sensitivity and specificity were 0.707, 92.3%(12/13) and 60.6%(40/66), respectively. When the cutoff value of age was 59 years, the area under ROC curve, sensitivity and specificity were 0.773, 92.3% (12/13) and 46.2% (30/65), respectively. Taking the cutoff value of 10.9 HU as the degree of enhancement in arterial phase (DE1), the area under ROC curve, sensitivity and specificity were 0.774, 84.6% (11/13) and 77.3% (51/66), respectively. Using a cutoff value of 30.3 HU, the sensitivity, specificity, and the area under ROC curve were 84.6% (11/13), 65.2% (43/66), and 0.731, respectively. Conclusions: CT examination in addition to clinical data can be very helpful for the differential diagnosis of GLMs from GSTs in maximum diameter ≤5 cm.

T-type Ca(2+) channels mediate neurotransmitter release in retinal bipolar cells

Transmitter release in neurons is thought to be mediated exclusively by high-voltage-activated (HVA) Ca(2+) channels. However, we now report that, in retinal bipolar cells, low-voltage-activated (LVA) Ca(2+) channels also mediate neurotransmitter release. Bipolar cells are specialized neurons that release neurotransmitter in response to graded depolarizations. Here we show that these cells express T-type Ca(2+) channel subunits and functional LVA Ca(2+) currents sensitive to mibefradil. Activation of these currents results in Ca(2+) influx into presynaptic terminals and exocytosis, which we detected as a capacitance increase in isolated terminals and the appearance of reciprocal currents in retinal slices. The involvement of T-type Ca(2+) channels in bipolar cell transmitter release may contribute to retinal information processing.

[Cloning and expression of nisZ gene in Lactococcus lactis]

The gene encoding the precursor of nisin was amplified by PCR using the lambda HJ-3 DNA as the template, which contained the entire nisin biosynthesis gene cluster from Lactococcus lactis AL2 with high yield of nisin, and was cloned into pMG36e. The recombinant plasmid pHJ201 was introduced into Lactococcus lactis NZ9800 by electroporation. pHJ201 is very stable in L. lactis NZ9800. Antimicrobial activity test and Tricine-SDS-PAGE analysis revealed that L. lactis NZ9800 harbouring pHJ201 restored ability of nisin production, but the production level was markedly lower than L. lactis AL2. The result of DNA sequence analysis indicated that Nisin Z is produced by L. lactis AL2.

Voltage-dependent Na(+) currents in mammalian retinal cone bipolar cells

Voltage-dependent Na(+) channels are usually expressed in neurons that use spikes as a means of signal coding. Retinal bipolar cells are commonly thought to be nonspiking neurons, a category of neurons in the CNS that uses graded potential for signal transmission. Here we report for the first time voltage-dependent Na(+) currents in acutely isolated mammalian retinal bipolar cells with whole cell patch-clamp recordings. Na(+) currents were observed in approximately 45% of recorded cone bipolar cells but not in rod bipolar cells. Both ON and OFF cone bipolar cells were found to express Na(+) channels. The Na(+) currents were activated at membrane potentials around -50 to -40 mV and reached their peak around -20 to 0 mV. The half-maximal activation and steady-state inactivation potentials were -24.7 and -68.0 mV, respectively. The time course of recovery from inactivation could be fitted by two time constants of 6.2 and 81 ms. The amplitude of the Na(+) currents ranged from a few to >300 pA with the current density in some cells close or comparable to that of retinal third neurons. In current-clamp recordings, Na(+)-dependent action potentials were evoked in Na(+)-current-bearing bipolar cells by current injections. These findings raise the possibility that voltage-dependent Na(+) currents may play a role in bipolar cell function.

Chronic levothyroxin treatment is associated with ion channel abnormalities in cardiac and neuronal cells

1. We investigated the ion currents responsible for repolarization of guinea-pig isolated myocytes (ICa) and rat hippocampal CA1 neurons (IA and IK) by means of the whole-cell holding technique. 2. The rat hypertrophied heart, induced by levothyroxin, caused exaggerated cardiac arrhythmias after coronary ischaemia-reperfusion. 3. We found an enhanced ICa in guinea-pig isolated myocytes and decreased IA and IK in rat hippocampal CA1 neurons following levothyroxin treatment. Blockade of the outward K+ current and an increment in inward Ca2+ current by chronic levothyroxin treatment contributed to the delayed repolarization and aggravated cardiac arrhythmias. 4. Animals treated with chronic levothyroxin may serve as pathological models for the investigation of the pattern of ion channel disorders with regard to impaired repolarization and aggravated cardiac arrhythmias.

Bepridil inhibition of sodium current in rat hippocampal CA1 neurons

AIM

To study the effects of bepridil on sodium current in rat hippocampal neurons.

METHODS

All experiments were performed on acutely isolated hippocampal pyramidal neurons by means of whole-cell patch-clamp techniques. Recording media contained ion channel blockers to allow the selective activation of voltage-dependent sodium currents.

RESULTS

Bepridil reduced the amplitudes of sodium current in time- and concentration-dependent manners. The half-blocking time was about 10 min in bepridil 10 micromol.L-1, and IC50 was 2.6 (2.3-2.9) micromol.L-1. Bepridil 10 micromol.L-1 shifted the maximal activation of sodium current from -50 mV to -40 mV, and the characteristic voltage of inactivation from -71 mV to -89 mV without changing the slope factor.

CONCLUSION

Bepridil blocked voltage-dependent sodium current of hippocampal CA1 neurons and might have therapeutic actions for ischemia-induced brain damage.

Histamine aggravated levothyroxine-induced cardiomyopathy in guinea pigs

AIM

To study effects of histamine on cardiomyopathy.

METHODS

Cardiomyopathy model was developed in guinea pig by i.p. levothyroxine 0.5 mg.kg-1.d-1 for 10 d. Langendroff's hearts were perfused. ECG and contractile force were recorded. Histamine (5 micrograms) was given by intra-aortic injection. Histamine content of coronary venous effluent was determined fluorometrically.

RESULTS

Attack of histamine on cardiomyopathy was severer than that in normal hearts. Tachycardia was more prominent; atrioventricular conduction block occurred earlier; decrease in coronary flow was more marked. Uptakes of histamine were 37% in the model and 19% in the normal hearts (P < 0.01).

CONCLUSION

Histamine aggravated levothyroxine-cardiomyopathy.

[Effects of ferulic acid on allergic reaction]

Ferulic acid (FA) 70, 140 mg.kg-1 ip clearly inhibited homologous passive cutaneous anaphylaxis (PCA) and degranulation of mast cells of calvarial periosteum, active and passive Arthus reactions in rats. Reversed cutaneous anaphylaxis in rats and Forssman cutaneous vasculitis in guinea pigs were suppressed by FA 140 mg.kg-1. The delayed hypersensitivity reaction induced by sheep red blood cell (SRBC) or dinitrochlorbenzene (DNCB) in mice were also dramaticaly inhibited by FA 100, 200 mg.kg-1. FA 200, 400 mg.kg-1 ig significantly enhanced phagocytic function of mononuclear phagocyte. These results suggest that FA has extensive inhibitory effects on type I, II, III, and IV allergic reactions.