隐匿性HBV感染患者HBVS基因突变特点及突变病毒株致瘤性研究

目的 研究肝病人群中隐匿性HBV感染(occult hepatitisB virus infection,OBI)患者HBVS基因主要亲水区(major hydrophilic region,MHR)的突变特点及突变病毒株的致瘤性。方法 回顾性分析2011年9月—2016年3月中国人民解放军总医院第五医学中心血清库中收集的10359例样本及其患者临床资料,分析OBI检出率及其HBVS基因MHR突变特点。通过细胞增殖、平板克隆、细胞划痕、细胞小室迁移和细胞周期等实验方法,分析1株典型的新型突变病毒株的致瘤性。结果 筛查出血清HBsAg阴性及HBVDNA阳性的OBI患者14例,OBI检出率为0.191%(14/7323)。14例患者中检出9种MHR突变类型,其中新发现126-127“RPCMNCTI”插入和F161S2种突变。细胞肿瘤表型实验结果显示,与空载体对照组和野生组细胞相比,突变组细胞的增殖、克隆形成和迁移能力均明显增加(P均<0.05)。结论 本研究显示肝病人群中有较高的OBI检出率,且多数患者可检出文献报道的OBI相关突变。HBVS基因126-127“RPCMNCTI”插入新型突变具有促进肿瘤生长的细胞生物学特点,可能会增加慢性HBV感染患者向肝癌进展的潜在风险。     

丙型肝炎病毒E2蛋白DNA疫苗诱导小鼠产生中和抗体的研究

目的探讨丙型肝炎病毒(HCV)包膜E2蛋白DNA疫苗诱导小鼠产生中和抗体的可行性。方法构建截除疏水性羧基末端的HCV包膜蛋白表达质粒pCI-1b661以及同时截除疏水性羧基末端和高变区1(HVR1)的表达质粒pCI-1b661Δ,转染293T细胞,以Western blot和ELISA检测细胞内和培养上清中的HCVE2蛋白,将两种表达质粒及空载体分别肌注免疫BALB/c小鼠,以ELISA检测小鼠血清中的HVR1抗体,以HCV假病毒颗粒(HCVpp)分析小鼠血清的中和活性。结果 2种表达质粒均能表达分泌性截短型E2蛋白。pCI-1b661免疫的8只小鼠血清中均可检测到HVR1抗体,而pCI-1b661Δ免疫血清中未检测到HVR1抗体。pCI-1b661和pCI-1b661Δ免疫血清对HCVpp的中和率分别为(78.5±13.8)%和(38.7±6.5)%,差异有显著性(P<0.01)。pCI-1b661免疫组小鼠血清的中和率与HVR1抗体水平呈正相关(r=0.967,P<0.01)。结论表达截短型E2蛋白的DNA疫苗能诱导产生HCV中和抗体,其主要成员为HVR1抗体。     

口腔颌面部血管瘤药物治疗研究进展

口腔颌面部血管瘤发病率较高,由于其具体的发病机制不清,是外科临床治疗的一个难点。既往治疗口腔颌面部血管瘤的多种药物取得良好的临床疗效,与传统的外科手术及物理等治疗相比,药物治疗具有操作相对简单、创伤小、不良反应轻等特点,现对硬化剂、抗癌药、干扰素、类固醇激素、有机化合物及免疫调节剂等药物在口腔颌面部血管瘤治疗研究中的进展予以综述。     

Spectral CT Imaging–Based Quantification of Iodized Oil Retention following Chemoembolization: Phantom and Animal Studies

PurposeTo evaluate accuracy of iodine quantification using spectral CT and the potential of quantitative iodized oil analysis as an imaging biomarker of chemoembolization.Materials and MethodsA phantom of an artificial liver with 6 artificial tumors containing different amounts of iodized oil (0–8 vol%) was scanned by spectral CT, and iodized oil density (mg/mL) and Hounsfield unit (HU) values were measured. In addition, VX2 hepatoma was induced in 23 rabbits. After chemoembolization using iodized oil chemoemulsion, the rabbits were scanned by spectral CT. The accumulation of iodized oil in the tumor was quantified in terms of iodized oil density and HUs, and the performances in predicting a pathologic complete response (CR) were evaluated by receiver operating characteristic curve analyses.ResultsThe mean difference between true iodine densities and spectral image–based measurements was 0.5 mg/mL. Mean HU values were highly correlated with mean iodine density (r² = 1.000, P < .001). In the animal study, a pathologic CR was observed in 17 of 23 rabbits (73.9%). The range of area under the curve values of iodine and HU measurements was 0.863–0.882. A tumoral iodine density of 3.57 mg/mL, which corresponds to 0.7 vol% iodized oil in the tumor, predicted a pathologic CR with a sensitivity of 70.6% and a specificity of 100.0%.ConclusionsSpectral CT imaging has a potential to predict tumor responses after chemoembolization by quantitatively assessing iodized oil in targets.     

Synthetic MRI is not yet ready for morphologic and functional assessment of patellar cartilage at 1.5 Tesla

PurposeThe purpose of this study was to compare morphologic assessment and relaxometry of patellar hyaline cartilage between conventional sequences (fast spin-echo [FSE] T2-weighted fat-saturated and T2-mapping) and synthetic T2 short-TI inversion recovery (STIR) and T2 maps at 1.5 T magnetic resonance imaging (MRI).MethodThe MRI examinations of the knee obtained at 1.5 T in 49 consecutive patients were retrospectively studied. There were 21 men and 28 women with a mean age of 45 ± 17.7 (SD) years (range: 18–88 years). Conventional and synthetic acquisitions were performed, including T2-weighted fat-saturated and T2-mapping sequences. Two radiologists independently compared patellar cartilage T2-relaxation time on conventional T2-mapping and synthetic T2-mapping images. A third radiologist evaluated the patellar cartilage morphology on conventional and synthetic T2-weighted images. The presence of artifacts was also assessed. Interobserver agreement for quantitative variables was assessed using intraclass correlation coefficient (ICC).ResultsIn vitro, conventional and synthetic T2 maps yielded similar mean T2 values 58.5 ± 2.3 (SD) ms and 58.8 ± 2.6 (SD) ms, respectively (P = 0.414) and 6% lower than the expected experimental values (P = 0.038). Synthetic images allowed for a 15% reduction in examination time compared to conventional images. On conventional sequences, patellar chondropathy was identified in 35 patients (35/49; 71%) with a mean chondropathy grade of 4.8 ± 4.8 (SD). On synthetic images, 28 patients (28/49; 57%) were diagnosed with patellar chondropathy, with a significant 14% difference (P = 0.009) and lower chondropathy scores (3.7 ± 4.9 [SD]) compared to conventional images. Motion artifacts were more frequently observed on synthetic images (18%) than on conventional ones (6%). The interobserver agreement was excellent for both conventional and synthetic T2 maps (ICC > 0.83). Mean cartilage T2 values were significantly greater on synthetic images (36.2 ± 3.8 [SD] ms; range: 29-46 ms) relative to conventional T2 maps (31.8 ± 4.1 [SD] ms; range: 26-49 ms) (P < 0.0001).ConclusionDespite a decrease in examination duration, synthetic images convey lower diagnostic performance for chondropathy, greater prevalence of motion artifacts, and an overestimation of T2 values compared to conventional MRI sequences.     

Sociodemographic determinants of Malaysian household’s use of and expenditure on alcohol: a regional comparison

Abstract

Aims: Alcohol consumption has become a serious public health concern. The objective of the present study is to investigate sociodemographic factors associated with alcohol consumption across regions of Malaysia.

Methods: Data are obtained from the Malaysian Household Expenditure Survey 2014, which contains 10,665 observations. Double-hurdle model is used to examine the consumption decision and amount decision of alcohol among households. Analyses are stratified by regions (Northern, East coast, Central and Southern).

Findings: Results show that age, household size, gender, ethnicity, marital status, education, employment status, location of residence and tobacco consumption are independently associated with alcohol consumption. Households headed by males and well-educated individuals are more likely to consume alcohol and also spend more compared with households headed by females and less-educated individuals. Being employed, non-Bumiputera and tobacco consumption seem to increase the likelihood of consuming alcohol. Household size is negatively associated with the amount spent on alcohol.

Conclusion: In conclusion, sociodemographic factors play an important role in determining alcohol consumption. It appears that factors associated with alcohol consumption vary across regions. Hence, policies that address regional differences in the sociodemographic factors associated with alcohol consumption are needed.     

New immunosuppressive agents in transplantation

Immunosuppressive agents have enabled the development of allogenic transplantation during the last 40 years, allowing considerable improvement in graft survival. However, several issues remain such as the nephrotoxicity of calcineurin inhibitors, the cornerstone of immunosuppressive regimens and/or the higher risk of opportunistic infections and cancers. Most immunosuppressive agents target T cell activation and may not be efficient enough to prevent allo-immunization in the long term. Finally, antibody mediated rejection due to donor specific antibodies strongly affects allograft survival.Many drugs have been tested in the last decades, but very few have come to clinical use. The most recent one is CTLA4-Ig (belatacept), a costimulation blockade molecule that targets the second signal of T cell activation and is associated with a better long term kidney function than calcineurin inhibitors, despite an increased risk of acute cellular rejection.The research of new maintenance long-term immunosuppressive agents focuses on costimulation blockade. Agents inhibiting CD40-CD40 ligand interaction may enable a good control of both T cells and B cells responses. Anti-CD28 antibodies may promote regulatory T cells. Agents targeting this costimulation pathways are currently evaluated in clinical trials.Immunosuppressive agents for ABMR treatment are scarce since anti-CD20 agent rituximab and proteasome inhibitor bortezomib have failed to demonstrate an interest in ABMR. New drugs focusing on antibodies removal (imlifidase), B cell and plasmablasts (anti-IL-6/IL-6R, anti-CD38…) and complement inhibition are in the pipeline, with the challenge of their evaluation in such a heterogeneous pathology.     

Correlation between magnetic resonance imaging characteristics and BRAF alteration status in individuals with optic pathway/hypothalamic pilocytic astrocytomas

Background and purposeMost individuals with optic pathway/hypothalamic pilocytic astrocytoma (OPHPA) harbor either the BRAF V600E mutation or KIAA1549-BRAF fusion (K-B). This study aimed to investigate the imaging characteristics of OPHPA in relation to BRAF alteration status.Materials and methodsSeven cases of OPHPA harboring either the BRAF V600E mutation or K-B fusion were included in the study. Preoperative magnetic resonance imaging (MRI) was assessed for degree of T2 hyperintensity on T2-weighted images (T2WI) and the ratio of nonenhancing T2 or fluid-attenuated inversion recovery (FLAIR) hyperintense area to the contrast enhanced area (CE) on gadolinium-enhanced-T1 weighted images (T2/FLAIR-CE mismatch). The T2 signal intensity was normalized to cerebrospinal fluid (T2/CSF) for both the V600E and K-B group and compared. T2/FLAIR-CE mismatch was assessed by calculating the proportion of the tumor volume of nonenhancing high T2 signal intensity to the whole lesion (nonenhancing and enhancing components).ResultsFour and three cases of OPHPA harboring the BRAF V600E mutation and K-B, respectively, were analyzed. The T2/CSF value was higher in the K-B group than in the V600E group. Moreover, the V600E group had a larger T2/FLAIR-CE mismatch than the K-B group.ConclusionsThe BRAF alteration status in individuals with OPHPA was associated with preoperative MRI by focusing on T2 signal intensity and T2/FLAIR-CE mismatch. The BRAF V600E mutation was associated with a lower T2/CSF value and larger T2/FLAIR-CE mismatch, whereas K-B fusion was associated with a higher T2/CSF value and smaller T2/FLAIR-CE mismatch.