[Chronic hepatitis B virus infection-related osteoporosis]

Clinically, osteoporosis is often observed in combination with different disease states in patients with hepatitis B virus infection, but because of its complex pathogenesis, non-specific early clinical manifestations, and inadequate clinical attention, the patient's prognosis is frequently affected. This review summarizes the pathogenesis, diagnosis, and treatment of chronic hepatitis B virus infection-related osteoporosis in order to raise awareness of the disease.

[Roles of the CXCR1/CXCL8 axis in abnormal proliferation of bile duct epithelial cells in primary biliary cholangitis]

Objective: To investigate the role of the CXC chemokine receptor 1 (CXCR1)/CXC chemokine ligand 8 (CXCL8) axis in the abnormal proliferation of bile duct epithelial cells in primary biliary cholangitis (PBC). Methods: 30 female C57BL/6 mice were randomly divided into the PBC model group (PBC group), reparixin intervention group (Rep group), and blank control group (Con group) in an in vivo experiment. PBC animal models were established after 12 weeks of intraperitoneal injection of 2-octanoic acid coupled to bovine serum albumin (2OA-BSA) combined with polyinosinic acid polycytidylic acid (polyI:C). After successful modelling, reparixin was injected subcutaneously into the Rep group (2.5 mg · kg(-1) · d(-1), 3 weeks). Hematoxylin-eosin staining was used to detect histological changes in the liver. An immunohistochemical method was used to detect the expression of cytokeratin 19 (CK-19). Tumor necrosis factor-α (TNF-α), γ-interferon (IFN-γ) and interleukin (IL)-6 mRNA expression were detected by qRT-PCR. Western blot was used to detect nuclear transcription factor-κB p65 (NF-κB p65), extracellularly regulated protein kinase 1/2 (ERK1/2), phosphorylated extracellularly regulated protein kinase 1/2 (p-ERK1/2), Bcl-2-related X protein (Bax), B lymphoma-2 (Bcl-2), and cysteine proteinase-3 (Caspase- 3) expression. Human intrahepatic bile duct epithelial cells were divided into an IL-8 intervention group (IL-8 group), an IL-8+Reparicin intervention group (Rep group), and a blank control group (Con group) in an in vitro experiment. The IL-8 group was cultured with 10 ng/ml human recombinant IL-8 protein, and the Rep group was cultured with 10 ng/ml human recombinant IL-8 protein, followed by 100 nmol/L Reparicin. Cell proliferation was detected by the EdU method. The expression of TNF-α, IFN-γ and IL-6 was detected by an enzyme-linked immunosorbent assay. The expression of CXCR1 mRNA was detected by qRT-PCR. The expression of NF-κB p65, ERK1/2 and p-ERK1/2 was detected by western blot. A one-way ANOVA was used for comparisons between data sets. Results: The results of in vivo experiments revealed that the proliferation of cholangiocytes, the expression of NF-κB and ERK pathway-related proteins, and the expression of inflammatory cytokines were increased in the Con group compared with the PBC group. However, reparixin intervention reversed the aforementioned outcomes (P<0.05). In vitro experiments showed that the proliferation of human intrahepatic cholangiocyte epithelial cells, the expression of CXCR1 mRNA, the expression of NF-κB and ERK pathway-related proteins, and the expression of inflammatory cytokines were increased in the IL-8 group compared with the Con group. Compared with the IL-8 group, the proliferation of human intrahepatic cholangiocyte epithelial cells, NF-κB and ERK pathway-related proteins, and inflammatory indicators were significantly reduced in the Rep group (P < 0.05). Conclusion: The CXCR1/CXCL8 axis can regulate the abnormal proliferation of bile duct epithelial cells in PBC, and its mechanism of action may be related to NF-κB and ERK pathways.

[Associations between different levels of blood pressure and risk of prediabetes]

Objective: To explore sex and rural-urban differences in the associations of different blood pressure levels with the risk of prediabetes. Methods: We used a multi-stage stratified cluster random sampling method to investigate 21 637 residents aged ≥18 years from 10 survey areas in Hubei province in 2020. The data on questionnaire, physical measurements, and laboratory indicators of the participants were collected. The associations of different blood pressure levels with risk of prediabetes by sex and regions were analyzed using multivariate logistic regressions after complex weighting. Results: A total of 16 111 subjects were included. The prevalence (95%CI) of prediabetes, impaired fasting glucose (IFG), impaired glucose tolerance (IGT), and IFG complicated with IGT were 25.1% (14.4%-35.9%), 12.7% (3.2%-22.1%), 8.1% (6.3%-9.8%), and 4.4% (2.3%-6.5%), respectively. After multivariate adjustment, the risk of prediabetes, IFG, IGT, and IFG complicated with IGT increased with the increment of blood pressure (both P for trend <0.05). The positive dose-response relationships between blood pressure levels and risk of prediabetes were also significant among male, urban, and rural residents (both P for trend <0.05), and the interactions between sex and blood pressure showed significant associations for risk of prediabetes and IGT (both P for interaction <0.05). Conclusions: Higher blood pressure levels were associated with an increased risk of prediabetes. The association with prediabetes was stronger in males, but no significant difference was found between urban and rural residents. More distinctive and effective prevention and control strategies should be developed for different populations.

[Precise diagnosis and treatment of hemophagocytic lymphohistiocytosis guided by cytokine patterns]

Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening entity which presents as multi-organ dysfunction caused by overactivated T cell and macrophage and overwhelming hyperinflammation. Cytokine storm is the key pathophysiology of HLH. Due to the diversity of the underlying diseases, the difference of disease severity and the non-specific clinical manifestation, the early diagnosis and standardized treatment is a great challenge for clinicians. According to previous clinical studies, serum cytokine measurement is helpful for rapid diagnosis of HLH and the differentiation of HLH from other diseases caused by hypercytokinemia, and it perfoms well to clarify subtypes of HLH, to stratify patients with different risks and to predict the prognosis and outcome. Thus, serum cytokine measurement could be a useful tool for the precise diagnosis and treatment of HLH.

Immersive Learning Design for Technology Education: A Soft Systems Methodology

Science, technology, engineering and mathematics (STEM) education is a globalized trend of equipping students to facilitate technological and scientific developments. Among STEM education, technology education (TE) plays a significant role in teaching applied knowledge and skills to create and add value to systems and products. In higher education, the learning effectiveness of the TE assisted by the immersive technologies is an active research area to enhance the teaching quality and learning performance. In this study, a taught subject of radio frequency identification (RFID) assisted by using mixed reality technologies in a higher education institution was examined, while the soft systems methodology (SSM) was incorporated to evaluate the changes in learning performance. Under the framework of SSM, stakeholders’ perceptions toward immersive learning and RFID education are structured. Thus, a rich picture for teaching activities is established for subject control, monitoring, and evaluation. Subsequently, the design of TE does not only satisfy the students’ needs but also requirements from teachers, industries, and market trends. Finally, it is found that SSM is an effective approach in designing courses regarding hands-on technologies, and the use of immersive technologies improves the learning performance for acquiring fundamental knowledge and application know-how.

Survey data on the impact of COVID-19 on parental engagement across 23 countries

This data article describes the dataset of the International COVID-19 Impact on Parental Engagement Study (ICIPES). ICIPES is a collaborative effort of more than 20 institutions to investigate the ways in which, parents and caregivers built capacity engaged with children's learning during the period of social distancing arising from global COVID-19 pandemic. A series of data were collected using an online survey conducted in 23 countries and had a total sample of 4,658 parents/caregivers. The description of the data contained in this article is divided into two main parts. The first part is a descriptive analysis of all the items included in the survey and was performed using tables and figures. The second part refers to the construction of scales. Three scales were constructed and included in the dataset: 'parental acceptance and confidence in the use of technology', 'parental engagement in children's learning' and 'socioeconomic status'. The scales were created using Confirmatory Factor Analysis (CFA) and Multi-Group Confirmatory Analysis (MG-CFA) and were adopted to evaluate their cross-cultural comparability (i.e., measurement invariance) across countries and within sub-groups. This dataset will be relevant for researchers in different fields, particularly for those interested in international comparative education.

Gout in China, 1990-2017: the Global Burden of Disease Study 2017

OBJECTIVE

The aim of the study was to estimate the gout burden and risk factors in China from 1990 to 2017.

STUDY DESIGN

The Global Burden of Disease (GBD) Study uses various analytical tools and a diverse set of data sources to generate comparable estimates of deaths and mortality rates broken down by age, sex, cause, year, and geography.

METHODS

We used the results from the GBD Study 2017 to compare disability-adjusted life years (DALYs), prevalence, incidence, and risk factors of gout in China. The median of the percentage change and 95% uncertainty intervals were determined for the period between 1990 and 2017.

RESULTS

The age-standardized DALY rate, prevalence, and incidence increased 6.92%, 6.88%, and 6.16%, respectively, in China from 1990 to 2017. Although the rates of gout both globally and in China were increasing, the range of change for males in China was larger than that of the global level. All risk factors combined accounted for 30.04% of gout DALYs in 2017. The leading risk factors for gout DALYs were high body mass index and impaired kidney function, and the proportion of high body mass index increased significantly from 10.67% to 24.31%, whereas the proportion of impaired kidney function remained basically unchanged.

CONCLUSIONS

The age-standardized DALY rate, prevalence, and incidence in China have increased progressively since 1990. Increasing attention on body weight management should be prioritized for controlling the rising prevalence of gout in the young and middle-aged population.

[Long-term outcome of childhood T-cell acute lymphoblastic leukemia treated with modified national protocol of childhood leukemia in China-acute lymphoblastic leukemia 2008]

Objective: To analyse the long-term efficacy in childhood T-cell acute lymphoblastic leukemia (T-ALL) cases enrolled in the national protocol of childhood leukemia in China-acute lymphoblastic leukemia (NPCLC-ALL) 2008. Methods: Clinical data of 96 patients diagnosed as T-ALL and treated with NPCLC-ALL2008 protocol between January 2009 and December 2017 in the Department of Hematology-Oncology, the Children's Hospital, Zhejiang University School of Medicine were analyzed retrospectively. Predictive value of minimal residual disease (MRD) monitored by flow cytometry was analyzed. Kaplan-Meier method was used for long-term survival analysis. Results: A total of 96 evaluable patients with newly diagnosed T-ALL were analysed, including 72 males and 24 females. The age was 9.5 (ranged from 1.0 to 16.0) years. The follow-up time was 5.7 (ranged from 1.0 to 9.7) years. Among 96 patients, 92 (96%) achieved complete remission. The 5-year event free survival (EFS) and overall survival (OS) rates were (61±6) % and (70±5) %, respectively. Relapse occurred in 18 cases and the 5-year cumulative incidence of relapse was (27±6) %. Twenty-four patients died. The 5-year OS rates of patients with MRD>5% on day 15 of induction therapy was significantly worse than those with MRD≤5% ((60±12) % vs. (72±6) %, χ(2)=3.904, P=0.048) . The 5-year EFS and OS rates were obviously lower in patients with MRD>10% before the consolidation therapy ((50±35) %). The 5-year OS rates of patients with relapsed disease was significantly worse than those without ((26±13) % vs. (81±5) %, χ(2)=18.411, P<0.01). The earlier the relapse, the worse the prognosis. The 5-year OS rates for patients relapsed within 6 months, within 3 years and more than 3 years, were (25±22) %, (30±14) % and (50±35) % respectively (χ(2)=13.207, P<0.01). Conclusions: NPCLC-ALL2008 protocol is effective for childhood T-ALL. The MRD guided accurate risk stratification and individualized treatment can reduce the relapse and improve the survival rate of pediatric T-ALL.

Deployment of Virtual Reality (VR) to Promote Green Burial

Population projections for Hong Kong suggest that the city will accommodate 8.22 million people in 2043. One in every three people are expected to be older than 65 in 2066. The long-held Chinese traditions for burial of deceased with reverence and honour, coupled with the chronic land shortage have presented an excessive demand for cemetery space. Niches are seldom recycled and the inadequate supply of new columbarium niche requires the family of the deceased to consider alternative way for keeping cremated ashes. To ease the demand, “green burial” has been launched and promoted by the HKSAR government through different print and social media. Currently, scattering of cremains in Gardens of Remembrance or at sea are the two common ways to perform green burial. The public acceptance of green burial is still a questionable and is under-researched. This study is going to deploy innovative technology, virtual reality (VR) to increase physical and psychological fidelity in highly resembled scenarios for the people. On one hand, VR gives immeasurable value to people when they are enabled to navigate different circumstances (physical fidelity) before considering the use of green burial. On the other hand, VR enables the people to engage in different mental processes (psychological fidelity) replicated from an array of cognitive reaction and sentiments with the choice of green burial. In order to optimize the configuration of the VR settings, we will conduct a face-to-face, semi-structured and in-depth interview with different practitioners. In the study, we explore: (1) To what extent the enhancement of physical fidelity of innovative technologies debunk public’s misconception of green burial? (2) To what extent the enhancement of psychological fidelity of innovative technologies debunk public’s misconception of green burial? (3) To what extent the simulated experience derived from innovation technologies change the public acceptance of green burial?

[Predictive value of cytokines and procalcitonin on infection in children with hematological malignancies]

Objective: To explore the value of cytokines and procalcitonin (PCT) in predicting the potential pathogen and the severity of infection in children with hematological malignancies. Methods: This was a prospective cohort study. A total of 1 543 children (3 912 episodes) with hematological malignancies admitted to the Department of Hematology/Oncology in Children's Hospital of Zhejiang University School of Medicine from November 2010 to June 2018 were prospectively enrolled in this study. According to the pathogen, the patients were divided into sepsis group with positive blood culture (380 patients/608 episodes), sepsis group with negative blood culture (539/1 484), non-septic infection group (549/1 709), viral infection group (18/21) and fungal infection group (57/90). The patients were also divided into two groups in either shock group (171/187) or non-shock group (1 372/3 725). Meanwhile, 89 children (112 episodes) with matched hematological malignancies without fever were enrolled as the control group. The levels of PCT and cytokines were measured for detecting the potential relationship between these markers and infection severity. Mann-Whitney U test or Kruskal-Wallis H test was used to compare the differences between groups. The Receiver Operator Characteristic curve analysis was used to explore the predictive value. Results: (1) There were significantly higher levels of interleukin (IL) 6 (H=210.002, P<0.01), IL-10 (H=223.045, P<0.01), and PCT (H=76.799, P<0.01) in the infection group, with area under curre (AUC) of 0.67 (95%CI 0.64-0.69), 0.69 (95%CI 0.66-0.71) and 0.59 (95%CI 0.56-0.61), respectively. (2) Among the patients in the shock group, IL-6 (Z=11.460, P<0.01), IL-10 (Z=14.242, P<0.01) and PCT (Z=10.813, P<0.01) were significantly higher than those in the non-shock group, with the AUC of 0.75 (95%CI 0.70-0.79), 0.81 (95%CI 0.77-0.84) and 0.73 (95%CI 0.69-0.77), respectively. (3) In patients with septic shock, the incidence of Gram negative bacteria (GNB) infection (60 episodes) was significantly higher than Gram positive bacteria (GPB) infection (22 episodes) (χ(2)=29.665, P<0.01). The AUC of IL-6, IL-10 and PCT for predicting GNB infection were 0.75 (95%CI 0.72-0.78), 0.82 (95%CI 0.79-0.85) and 0.67 (95%CI 0.63-0.70), respectively. (4) The predictive power of IL-6, IL-10 and PCT combination (AUC=0.994) was superior to IL-10 alone (AUC=0.810) in predicting septic shock (Z=10.211, P<0.01). Conclusions: IL-6 and IL-10 are better predictors of GNB infection than PCT in hematology-oncology children. Furthermore, the combination of these two cytokines and PCT is more valuable in predicting the severity of infection.

Prognostic significance of the Musashi-2 (MSI2) gene in childhood acute lymphoblastic leukemia

The prognostic value of the Musashi-2 (MSI2) gene has not yet been studied in childhood acute lymphoblastic leukemia (ALL). In our study, MSI2 mRNA levels of 119 childhood patients with newly-diagnosed ALL were examined and analyzed with regard to clinical characteristics and outcomes. ALL patients demonstrated significantly higher MSI2 mRNA levels than healthy controls. In addition, MSI2 mRNA levels were correlated with the disease status and IK6 mutation status. Survival analyses showed that higher MSI2 mRNA levels predicted worse outcomes in patients with childhood ALL. Moreover, in multivariate analyses, MSI2 mRNA overexpression retained its value as an independent risk factor for overall survival (OS), but not for event free survival (EFS). We conclude that high MSI2 mRNA level predicts adverse prognosis and seems to be useful as a novel prognostic factor for patients with childhood ALL.

[Facial symmetry after conservative treatment of unilateral condylar fracture in children: a three-dimensional study]

Objective: To investigate the influence of condylar fractures on the growth of condylars after conservative treatments by three-dimensional measurement. Methods: Twenty three children with unilateral condylar fracture followed-up for at least 1 year in Shanghai Ninth People's Hospital were included from June 2016 to March 2017. CT scans were performed for each patient. Three-dimensional virtual skulls were reconstructed and measuring points were defined with Simplant 11.04 software. The depth of glenoid fossa, height of articular eminence, width, height and depth of condylar, deviation of pogonion were measured. Statistical analyses were conducted to assess difference between the bifid group and the normal group. Results: No difference was observed in the vertical position of crest of the articular eminence between two groups (P=0.110). The vertical position of roof of the glenoid fossa in bifid side was significantly superior than the one in normal side (P=0.010). Bifid side had a shorter (P=0.002) and wider(P=0.002) condylar than normal side did. No difference was observed in the depth of condylar between two groups (P=0.071). The average deviation of pogonion was (0.69±1.75) mm (P=0.072) from sagittal plan. Conclusions: This short-termed study indicates that children's growth potential of condylar is under average after conservative treatments. Because the bone hyperosteogeny of glenoid fossa compensates the hypotrophy of condylar, no deviation of pogonion is detected.

Identification of serum metabolites associated with obesity and traditional risk factors for metabolic disease in Chinese adults

BACKGROUND AND AIMS

Obesity is a major worldwide health problem and is often associated with many metabolic diseases. Levels of several serum-specific metabolites may be altered in patients with these metabolic diseases. We aimed to investigate the associations of serum metabolite levels with obesity and traditional risk factors for metabolic disease in Chinese individuals.

METHODS AND RESULTS

Six-hundred Chinese individuals undergoing annual physical exams were recruited and categorized into overweight/obese and control groups (1:1 ratio). We simultaneously quantified the serum lysophosphatidylcholine (LPC), branched-chain amino acids (BCAA), aromatic amino acids (AAA), 25-hydroxyvitamin D, glutamine (Gln), glutamic acid (Glu), and Gln/Glu ratio levels using our previously established targeted serum metabolomic method. The overweight/obesity group had significantly higher levels of BCAA, AAA, and Glu, as well as lower levels of unsaturated LPC, Gln, and Gln/Glu, than the control group. Correlation analyses revealed significant and positive relationships of saturated LPC, BCAA, AAA, and Glu with blood pressure, glucose, triglycerides, apolipoprotein B, and high-sensitivity C-reactive protein, while unsaturated LPC, Gln, Gln/Glu, and 25-hydroxyvitamin D exhibited an opposite trend. In the multifactor logistic regression model, low unsaturated LPC and Gln/Glu, as well as high BCAA and AAA levels, were found to be independent risk factors for obesity; the odds ratios (95% confidence interval) of the highest quartile compared to the lowest quartile were 0.241 (0.139-0.417), 0.436 (0.252-0.755), 3.944 (2.094-7.430), and 2.357 (1.274-4.361) (P < 0.01), respectively.

CONCLUSION

LPC, BCAA, AAA, and Gln/Glu are significantly related to obesity development and risk factors of some metabolic diseases.

Glucagon-Like Peptide-1 (GLP-1) Treatment Ameliorates Cognitive Impairment by Attenuating Arc Expression in Type 2 Diabetic Rats

Background

Glucagon-like peptide-1 (GLP-1) has been reported to exert some beneficial effects on the central nervous system (CNS). However, the effect of GLP-1 on cognitive impairment associated with type 2 diabetes is not well known. This study investigated the effect of GLP-1 on ameliorating memory deficits in type 2 diabetic rats.

Material/Methods

Type 2 diabetic rats were induced by a high-sugar, high-fat diet, followed by streptozotocin (STZ) injection and then tested in the Morris Water Maze (MWM) 1 week after the induction of diabetes. The mRNA expression of Arc, APP, BACE1, and PS1 were determined by real-time quantitative PCR, and the Arc protein was analyzed by immunoblotting and immunohistochemistry.

Results

Type 2 diabetic rats exhibited a significant decline in learning and memory in the MWM tests, but GLP-1 treatment was able to protect this decline and significantly improved learning ability and memory. The mRNA expression assays showed that GLP-1 treatment markedly reduced Arc, APP, BACE1, and PS1 expressions, which were elevated in the diabetic rats. Immunoblotting and immunohistochemistry results also confirmed that Arc protein increased in the hippocampus of diabetic rats, but was reduced after GLP-1 treatment.

Conclusions

Our findings suggest that GLP-1 treatment improves learning and memory deficits in type 2 diabetic rats, and this effect is likely through the reduction of Arc expression in the hippocampus.

Effectiveness of bacterial infection-related cytokine profile (BIRCP) determination for monitoring pathogen infections in children with hemopathy in the bone marrow inhibition phase

Serum cytokine profiles were analyzed before and after infection in children with hemopathy in the bone marrow inhibition phase to explore the utility of cytokine variations for detecting infections. Serum Th1/Th2 cytokine levels, including tumor necrosis factor, interleukin (IL)-2, IL-4, IL-6, IL-10, and interferon, were quantitatively determined by cytometric bead array technology in 480 cases (230 children) of children with hemopathy in the bone marrow inhibition phase with signs of infection, such as fever, and without, to establish baseline and affected levels for comparison with healthy control children. We used the cytokine profile of infected, blood culture-positive children to establish a bacterial infection-related cytokine profile (BIRCP) for predicting infections by pathogens in blood culture-negative children. Overall, 82.9% of children with Gram-negative bacterial infections were accompanied by marked increases of IL-6 and IL-10 levels [>10 times (means ± SD)], whereas only a mild increase of IL-6 levels occurred in Gram-positive bacteria-infected children [>2 times (means ± SD)] and only a mild increase of IFN-γ levels occurred in fungal culture-positive children [>2 times (means ± SD)]. Gram-positive bacterial and fungal infections did not cause a marked increase in IL-6 or IL- 10 levels. The effective rate (86.05%, N = 43) of infectious cases predicted by BIRCP was significantly higher than that obtained using traditional methods for selecting antibiotics based on clinical indications (65.45%, N = 55, P < 0.05). In summary, BIRCP can be used to predict the infections by pathogens in children with hemopathy and to select appropriate antibiotics.

Voxel-based approach to generate entire human metacarpal bone with microscopic architecture for finite element analysis

With the development of micro-computed tomography (micro-CT) technology, it is possible to construct three-dimensional (3D) models of human bone without destruction of samples and predict mechanical behavior of bone using finite element analysis (FEA). However, due to large number of elements required for constructing the FE models of entire bone, this demands a substantial computational effort and the analysis usually needs a high level of computer. In this article, a voxel-based approach for generation of FE models of entire bone with microscopic architecture from micro-CT image data is proposed. To enable the FE analyses of entire bone to be run even on a general personal computer, grayscale intensity thresholds were adopted to reduce the amount of elements. Human metacarpal bone (MCP) bone was used as an example for demonstrating the applicability of the proposed method. The micro-CT images of the MCP bone were combined and converted into 3D array of pixels. Dual grayscale intensity threshold parameters were used to distinguish the pixels of bone tissues from those of surrounding soft tissues and improve predictive accuracy for the FE analyses with different sizes of elements. The method of selecting an appropriate value of the second grayscale intensity threshold was also suggested to minimize the area error for the reconstructed cross-sections of a FE structure. Experimental results showed that the entire FE MCP bone with microscopic architecture could be modeled and analyzed on a personal computer with reasonable accuracy.

Versatile computer-controlled system for characterization of gas sensing materials

Design of a system used for characterizing gas sensing materials is described. It is distinctive of being able to measure electrical and optical responses of a sample simultaneously, control a number of measurement parameters, perform fast exchange of gaseous environment, and be fully controlled automatically. These features make the system to be versatile in determining most concerned performance indexes of a gas sensing material (e.g., sensitivity, stability, selectivity, response/recovery times, etc.) as functions of various combinations of measurement conditions (e.g., gas concentrations, temperature, total pressure, content of interferants, photo assist, relative humidity, soaking time in a fixed gas concentration, and number of switching cycles in a dynamic test, etc.). Rationales of the designs associated with general gas sensing mechanics are discussed.

Myxovirus-1 and protein kinase haplotypes and fibrosis in chronic hepatitis C virus

Candidate genes, including myxovirus resistance-1 (Mx1), protein kinase (PKR), transforming growth factor-beta1 (TGF-beta), interleukin-10 (IL-10), and interferon-gamma (IFN-gamma), were evaluated for associations with liver fibrosis in 374 treatment-naive patients with genotype-1 chronic HCV infection [194 Caucasian Americans (CAs) and 180 African Americans (AAs)], using a genetic haplotype approach. Among the 18 haplotypes that occurred with a frequency >or=5% in the cohort overall, the Mx1-(-123C)-(+6886A)-(+19820G(379V))-(+38645T) (abbreviated Mx1-CAGT), and PKR-(+110T)-(+7949G)-(+13846A)-(+22937T)-(+40342T) (abbreviated PKR-TGATT) haplotypes were independently associated with less severe hepatic fibrosis (Ishak >or= 3 versus <3). These associations persisted after adjustment for potential confounders such as alcohol use, sex, age (which is strongly correlated with the estimated duration of HCV infection [Spearman's correlation coefficient (r(s)) = 0.6)], and race (for Mx1-CAGT: OR = 0.33; 95% CI: 0.16-0.68; P = 0.0027; and for PKR-TGATT: OR = 0.56; 95% CI: 0.32-0.98; P = 0.0405). Population structure was evaluated using the structured association method using data from 161 ancestry-informative markers and did not affect our findings. We used an independent cohort of 34 AA and 160 CA in an attempt to validate our findings, although notable differences were found in the characteristics of the two patient groups. Although we observed a similar protective trend for the Mx1-CAGT haplotype in the validation set, the association was not statistically significant.

CONCLUSION

In addition to other factors, polymorphisms in cytokine genes may play a role in the progression of HCV-related fibrosis; however, further studies are needed.

Hyperintensity of the precentral gyral subcortical white matter and hypointensity of the precentral gyrus on fluid-attenuated inversion recovery: variation with age and implications for the diagnosis of amyotrophic lateral sclerosis

BACKGROUND AND PURPOSE

Hyperintensity of the subcortical white matter (SWM) of the precentral gyrus and hypointensity of the precentral gyrus gray matter (PGGM) on fluid-attenuated inversion recovery (FLAIR) are described as potentially useful diagnostic findings in amyotrophic lateral sclerosis (ALS). A detailed study of the prevalence of these findings in various age groups has not been described.

METHODS

One hundred twenty-two patients underwent axial FLAIR brain examinations as part of either hearing loss or tinnitus evaluation. Examinations were randomly selected to reflect an even spread through the decades from ages 15 to 78 years and were reviewed by 2 readers, blinded to patient's age and sex, for the presence/absence of the above 2 signs. If SWM hyperintensity was present, it was graded as intense as caudate nucleus (grade 1) or insula (grade 2).

RESULTS

We identified 32 cases of grade 1 and 5 cases of grade 2 SWM hyperintensity, and 28 cases of PGGM hypointensity. Both signs showed significant Spearman correlation with increasing age (r = 0.55, P < .001 for grade 1, r = 0.45, P < .001 for grade 2 SWM hyperintensity, r = 0.45, P < .001 for PGGM hypointensity). Analysis of variance showed there was a significant difference between the different age groups (P < .001) for both signs. Grading of the SWM and PGGM signals were highly reproducible with very good interobserver agreement (r = 0.88, P < .001, and r = 0.97, P < .001, respectively).

CONCLUSION

This study suggests a statistically significant relationship between increasing age and the frequency of precentral gyrus SWM hyperintensity and PGGM hypointensity on FLAIR, and reinforces previous reports that these signs can be seen in patients who do not have ALS.

Association between angiotensinogen, angiotensin II receptor genes, and blood pressure response to an angiotensin-converting enzyme inhibitor

BACKGROUND

To identify the genetic contribution to the variation in blood pressure (BP) response to angiotensin-converting enzyme inhibitors (ACEIs), single-nucleotide polymorphisms (SNPs) in the angiotensinogen (AGT), angiotensin receptor 1 (AGTR1), and angiotensin receptor 2 (AGTR2) genes were evaluated for their association with BP response to ACEI in Chinese patients with hypertension in a 2-stage design.

METHODS AND RESULTS

We selected 1447 hypertensive patients from a 3-year benazepril postmarket surveillance trial and genotyped them for 14 SNPs in the AGT, AGTR1, and AGTR2 genes. The AGT rs7079 (C/T) SNP (3'-untranslated region) was significantly associated with the response of diastolic BP to benazepril (diastolic BP response: -7.4 mm Hg for subjects with the CC genotype, -8.9 mm Hg for CA, and -10.1 mm Hg for AA; P=0.001). Although there was no association of individual SNPs in the AGTR1 gene, there was a graded response between common haplotypes and systolic BP reduction in the order of haplotype 2 (H2)/lack of haplotype 3 (non-H3) (-13.6 mm Hg) > non-H2/non-H3 (-10.9 mm Hg) > H3/non-H2 (-6.6 mm Hg) (P=0.004). The total variations in response to ACEI therapy that were explained by the AGT SNP and AGTR1 haplotype groups were 13% for systolic and 9% to 9.6% for diastolic BP, respectively.

CONCLUSIONS

AGT SNP rs7079 and AGTR1 haplotypes were associated with BP reduction in response to ACEI therapy in hypertensive Chinese patients. This will be useful in future studies, providing genetic markers to predict the hypertensive response to ACEI therapy.

Hyperintensity of the middle cerebellar peduncles on fluid-attenuated inversion recovery imaging: variation with age and implications for the diagnosis of multiple system atrophy

BACKGROUND AND PURPOSE

T2 hyperintensity of the middle cerebellar peduncle (MCP) is described in a number of diseases, including multiple system atrophy (MSA). We hypothesize that mild MCP hyperintensity on fluid-attenuated inversion recovery (FLAIR) imaging can be a normal finding. To our knowledge, a detailed study of the prevalence of this finding in various age groups with the FLAIR sequence has not been described.

METHODS

One hundred twenty-two patients underwent an axial FLAIR examination of the brain as part of either a hearing loss or tinnitus work-up (ie, to exclude an acoustic neuroma or a retrocochlear cause). Subjects aged 15-78 years were included to reflect an even spread through the decades and were divided into 6 age groups. A radiologist and an MR imaging fellow graded the examinations subjectively, blinded to age: 0 for normal or 1 for the presence of MCP hyperintensity if the increased signal intensity was greater than that of adjacent pons and cerebellar white matter. Spearman rank correlation test of MCP hyperintensity with age and analysis of variance (ANOVA) were performed.

RESULTS

Of 122 patients, we identified 17 with MCP FLAIR hyperintensity. None of these patients had a clinical condition that could cause MCP hyperintensity. MCP hyperintensity did not show a statistically significant correlation with age (r = 0.05, P = .62). Patients were divided into 6 age groups, and ANOVA showed no statistically significant difference in the incidence of MCP hyperintensity between different age groups (P = .95). However, results were highly reproducible with excellent interobserver correlation (r = 0.97, P < .001).

CONCLUSIONS

Mild MCP FLAIR hyperintensity can occur normally, and this finding shows no relationship with age.

Metastatic choriocarcinoma: A rare cause of stroke in the young adult

A 20-year old woman presented with acute right hemiplegia 10 weeks after intrauterine fetal death at 34-weeks gestation (G1P0). A brain MRI showed a typical acute infarct in the left middle cerebral artery territory. A CT pulmonary angiography carried out 1 week later for sudden cardiopulmonary deterioration showed disseminated pulmonary metastases. The CT was extended to the abdomen and pelvis, which showed a uterine mass with bilateral theca lutein cysts. The radiological diagnosis of metastatic choriocarcinoma was made and was subsequently confirmed with the markedly increased serum beta-human chorionic gonadotrophin. A serum beta-human chorionic gonadotrophin is therefore considered worthwhile in any young female adult who presents with stroke.

Macroscopic vascular invasion in synovial sarcoma evident on MRI

We present a case of recurrent synovial sarcoma in the soft tissues of the calf, where MR imaging not only confirmed the diagnosis of tumour recurrence, but also demonstrated direct venous invasion and tumour thrombus within the popliteal vein and its tributaries. Venous invasion has particular relevance to synovial sarcoma prognostication and should be actively sought on MR imaging. To our knowledge this is the first reported case in the English literature of histologically proven macroscopic popliteal vein invasion from a synovial sarcoma demonstrated on MR imaging.

Acute subarachnoid haemorrhage: a rare presentation of cerebral dural sinus thrombosis

We report a case of cerebral dural sinus thrombosis presenting as acute subarachnoid haemorrhage and clinically mimicking an aneurysmal bleed. Awareness of this rare initial presentation of cerebral venous thrombosis is important and should be considered in the diagnostic work-up of acute subarachnoid haemorrhage. The radiologist plays a crucial role in making this often unsuspected but important diagnosis to enable prompt appropriate treatment.

The solitary enhancing cerebral lesion: can FLAIR aid the differentiation between glioma and metastasis?

BACKGROUND AND PURPOSE

The purpose of this study is to investigate the diagnostic utility of fluid-attenuated inversion recovery (FLAIR) in differentiating between glioma and metastasis by assessing for nonenhancing adjacent cortical signal intensity abnormality in patients who present with a solitary enhancing cerebral lesion.

METHODS

After approval from the institutional ethics committee was obtained, the MR imaging studies of 70 patients with a solitary enhancing lesion, without previous surgery or treatment, were reviewed. The axial FLAIR studies were initially reviewed for cortical involvement. If cortex involvement was detected, comparison with the axial T1, with and without gadolinium enhancement, was made to determine whether the cortex involvement was in an area without enhancement. If this was the case, the study was considered positive for glioma. Statistical analysis consisted of binary logistic regression and a 2 x 2 contingency table.

RESULTS

Involvement of the adjacent cortex with FLAIR signal intensity abnormality but without enhancement was seen in 19 of 70 patients; 16 were gliomas and 3 were solitary metastasis. The sensitivity and specificity of this finding were 44% and 91%, respectively. The positive predictive value for glioma was 84%.

CONCLUSION

FLAIR, when interpreted in concert with pre- and postgadolinium T1-weighted images, may be useful in differentiating glioma from metastasis when a solitary enhancing cerebral lesion is present. The presence of nonenhancing adjacent cortical involvement in a solitary enhancing lesion is a frequent and relatively specific sign.

A novel NOD2/CARD15 haplotype conferring risk for Crohn disease in Ashkenazi Jews

Crohn disease (CD) exhibits a 2-4-fold increased frequency in Jews as compared with other ethnic/racial groups. Three coding variants of the NOD2/CARD15 have been reported as independent disease-predisposing mutations (DPMs), but these were found in only 30%-40% of patients with CD and could not account for all the linkage between CD and the IBD1 locus. The aim of the present study was to explore whether additional DPMs at the IBD1 locus exist in the high-risk Jewish group. Sixty-four Ashkenazi Jewish and 147 non-Jewish white families were studied. Six microsatellite markers spanning IBD1 were genotyped for linkage analysis in subgroups stratified on NOD2/CARD15 DPM status. SNPs in NOD2/CARD15 (R702W, G908R, 1007fs, and S268P) were then genotyped in family and independent case-control samples. On the basis of initial results, sequencing was done on NOD2/CARD15-translated regions in 12 Jewish individuals. Subsequently, a new NOD2/CARD15 variant was genotyped and analyzed. After excluding the influence of the three DPMs, significant linkage of IBD1 to CD in Jews remained with two peaks at D16S403 (mean allele sharing [MAS] = 0.70] and D16S411 (MAS = 0.59). Further, we observed an increased frequency of a haplotype carrying only the 268S variant in Jewish patients (OR = 3.13, P=.0023) but not in non-Jews, suggesting the existence of a Jewish-specific additional disease-predisposing factor on this haplotype. Sequencing of this haplotype revealed a new variant (IVS8+158; JW1). The 268S-JW1 combination exhibited a further increased risk (OR = 5.75, P=.0005) and the highest population-attributable risk (15.1%) for CD among reported DPMs in Jews. In Ashkenazi Jews, unrecognized population-specific predisposing factor(s) exist on the 268S-JW1 haplotype at the IBD1 locus. This factor may contribute to the higher risk for CD in Ashkenazi Jews as compared with non-Jews.

Association of cytokine responses with disease severity in infants with respiratory syncytial virus infection

AIM

To explore the relationship between cytokine responses and severity of respiratory syncytial virus (RSV) infection in infants.

METHODS

Intracellular interleukin-4 (IL-4) and interferon-gamma (IFN-gamma) expression in peripheral blood CD3+ and CD8+ lymphocytes was measured by four-colour flow cytometry. Serum IL-12, IL-4 and IFN-gamma levels were also determined by enzyme-linked immunosorbent assay.

RESULTS

The frequency of IL-4 and IFN-gamma expression in CD3+CD8- cells was the same in RSV-infected, non-RSV-infected and control infants and in those with RSV bronchiolitis or RSV pneumonia, indicating that no Th2 predominance exists in the acute phase of RSV infection and RSV bronchiolitis. Furthermore, RSV-infected infants had a more frequent IFN-gamma expression in CD3+CD8+ cells than controls, and they also showed a much lower serum IL-4/ IFN-gamma ratio because of decreased IL-4 and elevated IFN-gamma, the latter being most prominent in RSV bronchiolitis. The serum IL-12 level in RSV-infected infants was the same as in control infants, while those with non-RSV infections had a much higher level. Serum IL-12, IFN-gamma and frequency of IFN-gamma expression in CD3+CD8+ cells in mild RSV infection were much higher than in controls, while no difference existed between severe cases and controls.

CONCLUSION

Type 2 cytokine predominance was not found in the acute phase of RSV infection and RSV bronchiolitis, but both were accompanied by enhanced production of IFN-gamma and a much higher serum IFN-gamma level than in healthy controls, especially in those with RSV bronchiolitis, suggesting a role in causing airway obstruction. IFN-gamma and IL-12 may also play a protective role in RSV infections by diminishing viral replication, and high levels of IL-12 and IFN-gamma may be associated with lessening of the severity of infection.

Human CYP1B1 Leu432Val gene polymorphism: ethnic distribution in African-Americans, Caucasians and Chinese; oestradiol hydroxylase activity; and distribution in prostate cancer cases and controls

Cytochrome P4501B1 (CYP1B1) is involved in the activation of many carcinogens and in the metabolism of steroid hormones, including 17beta-oestradiol (E2) and testosterone. We report a significant difference in the allele frequencies of two point mutations in the coding region of the CYP1B1 gene among Caucasian (n = 189), African-American (n = 52) and Chinese (Linxian) (n = 109) populations. A (C to G) transversion at position 1666 in exon 3, which results in an amino acid substitution of Leu432 to Val, was present in African-Americans with an allele frequency for Va1432 of 0.75, in Caucasians of 0.43, and in Chinese of 0.17. A (C to T) transition at position 1719 in exon 3, with no amino acid change (Asp449), appeared to be closely linked with the Val432 variant. Results using human lung microsomal preparations from individuals with the CYP1B1Val/Val and CYP1B1Leu/Leu genotypes indicate that Val432 variant may be a high activity allele and thus may contribute to the interindividual differences in CYP1B1 activity. Because CYP1B1 is involved in hormone and carcinogen metabolism, and given the disparate rates of prostate cancer among ethnic groups, we also evaluated the association of the CYP1B1 Leu432Val polymorphism with prostate cancer risk in a pilot case-control study. Among Caucasians, 34% of men with cancer (n = 50) were homozygous for the Val432 polymorphism, while only 12% of matched control subjects (n = 50) had this genotype. These preliminary data indicate that genetic polymorphisms in CYP1B1 might play an important role in human prostate carcinogenesis.

Sodium-calcium exchange affects local calcium signal decay and the rate of exocytotic secretion in single chromaffin cells

The effects of Na+ deprivation on local calcium signal decay and the rate of exocytotic secretion were measured in single bovine chromaffin cells to determine whether Na-Ca exchange influences the local cytosolic Ca2+ signal for neurohormone release. Na+ replacement with N-methylglucamine caused a marked slowing of the decay of the local Ca2+ signal near points of its initiation, as measured by high-resolution fluorescent Ca2+ imaging in the confocal laser scanning microscope. Na+ replacement also resulted in a doubling of the rate and magnitude of exocytotic secretion measured in single cells by high-resolution microamperometry. Release rates provide an independent measure of local active zone Ca2+. Five repetitive stimulations of the same cell in Na+-free, but not in Na+-containing, medium resulted in a progressively increasing rate of catecholamine release, suggesting an increasing level of active zone Ca2+ and a role of Na-Ca exchange activity in Ca2+ clearance between stimulations. As secretory activity and its triggering Ca2+ signals are known to be co-localized in active zones along the plasma membrane, the results suggest that Na-Ca exchange may influence the decay of the local Ca2+ signal for exocytotic secretion. This would be consistent with a contribution to local Ca2+ clearance by a novel mechanism utilizing the insertion of secretory vesicle Na-Ca exchangers into the plasma membrane during exocytosis.

Sulfating-activity and stability of cDNA-expressed allozymes of human phenol sulfotransferase, ST1A3*1 ((213)Arg) and ST1A3*2 ((213)His), both of which exist in Japanese as well as Caucasians

We recently found single amino acid substitutions ((213)Arg/His and (223)Met/Val) in polymorphic human phenol-sulfating phenol sulfotransferase (SULT: cDNAs encoding ST1A3, P PST or HAST1/2) among Caucasians and African-Americans. In a Japanese population (n = 143), allele frequencies of (213)Arg and (213)His were 83.2 and 16. 8%, respectively, but the (223)Val allele was not found. (213)His homozygosity was reportedly associated with both very low (>7-fold) sulfating activities of p-nitrophenol (at 4 microM) and low thermostability in platelets. Sulfating-activity determinations using recombinant (213)Arg- and (213)His-forms (ST1A3*1 and ST1A3*2, respectively) did not, however, reveal appreciable deficiency in [(35)S]3'-phosphoadenosine 5'-phosphosulfate (PAPS)-dependent sulfation of p-nitrophenol (4 microM) by ST1A3*2 (7.5 vs. 10.2 nmol/min/nmol SULT for ST1A3). Kinetic parameters for p-nitrophenol for p-nitrophenol sulfation supported the slight decrease in sulfating activities at 4 microM (K(m), 0.82 vs. 1.75 microM; V(max), 13.2 vs. 13.1 nmol/min/nmol SULT, respectively, for ST1A3*1 and *2). p-Nitrophenyl sulfate-dependent 2-naphthol sulfation by ST1A3*2 was 69% of that by ST1A3*1 (p<0.05). However, ST1A3*2 was remarkably unstable at 45 and 37 degrees C as compared to ST1A3*1. The lower p-nitrophenol sulfating activity of ST1A3*2 may explain the lower platelet p-nitrophenol sulfation in ST1A3*2 homozygotes. Protein instability and ST1A3 gene regulation may be both involved in the polymorphism of p-nitrophenol sulfation in human tissues.

Analyses of bronchial bulky DNA adduct levels and CYP2C9, GSTP1 and NQO1 genotypes in a Hungarian study population with pulmonary diseases

Carcinogen-DNA adducts may represent an intermediate end-point in the carcinogenic cascade and may reflect exposure to chemical carcinogens, as well as susceptibility and, ultimately, cancer risk. Interindividual variability in activity of enzymes involved in the metabolism of polycyclic aromatic hydrocarbons to mutagenic diol epoxides may predict adduct levels and, indirectly, lung cancer risk. Using 32P-postlabeling methods, the levels of bulky DNA adducts were determined in macroscopically normal bronchial tissues obtained from resected lobes of 143 Hungarian patients with lung malignancy and other pulmonary conditions. DNA from normal tissue was also evaluated for polymorphisms in cytochrome P450 2C9 (CYP2C9) at two sites, codons 144 (Arg/Cys) and 359 (Ile/Leu), for glutathione S-transferase P1 (GSTP1) at codon 105 and for NAD(P)H:quinone oxidoreductase (NQO1) at codon 187 (Pro/Ser). Using the Mann-Whitney U-test and analysis of variance, levels of adducts were evaluated in relation to variant genotypes, separately for smokers and non-smokers. As previously reported, bulky DNA adduct levels in smokers (n = 104) were estimated to be 54% higher than in non-smokers (n = 39) (8.6 +/- 4.2 versus 5.6 +/- 3.3 per 10(8) nucleotides, respectively, P < 0.01). Adduct levels were 16-29% higher in individuals with the homozygous Ile359/Ile359 CYP2C9 allele than in those heterozygous for the variant allele (Ile359/Leu359) [8.8 +/- 4.3 (n = 84) versus 7.6 +/- 3.5 (n = 20) for smokers and 5.8 +/- 3.5 (n = 32) versus 4.5 +/- 1.3 (n = 7) for non-smokers], although differences were not statistically significant. There were no clear differences in adduct levels in relation to genotypes of NQO1 or GSTP1. Although numbers of patients in this study are large in relation to many studies of carcinogen-DNA adducts, it is still possible that significant differences were not noted for polymorphisms in xenobiotic metabolizing enzymes due to relatively small numbers in stratified data.

Low frequency of CYP2A6 gene polymorphism as revealed by a one-step polymerase chain reaction method

Human cytochrome P450 2A6 (CYP2A6) has been shown to metabolically activate carcinogens and mutagens. Genetic polymorphisms for CYP2A6 have been reported previously in different ethnic groups using a two-step polymerase chain reaction (PCR) method to identify CYP2A6*1, CYP2A6*2 and CYP2A6*3. Moreover, a new truncated allele has been recently identified in a Japanese population. We report here a one-step PCR amplification of the CYP2A6 gene from human genomic DNA and the detection of intact CYP2A6 alleles by restriction enzyme digestion. The diagnostic exon (exon 3) of the CYP2A6 gene was amplified from human genomic DNA with a primer pair. The forward primer is unique to the CYP2A6 gene, which eliminates previous problems in amplifying two highly homologous CYP2A genes, CYP2A7 and CYP2A13, in humans. The resulting PCR products (214 bp) were digested with XcmI or DdeI to detect the presence of CYP2A6*2 or CYP2A6*3 alleles, respectively. The allelic frequencies for CYP2A6*2 were 2.3% (n = 320) in the Caucasian and 0.7% (n = 71) in the Chinese populations, respectively. CYP2A6*3 allelic frequency in the Chinese population was 0.7%; while no CYP2A6*3 allele was detected in the Caucasian population. The allelic frequencies are relatively low and the reason for this discrepancy between different methods is discussed.

Comparison of DNA adduct levels associated with exogenous and endogenous exposures in human pancreas in relation to metabolic genotype

Recently, we examined normal human pancreas tissue for DNA adducts derived from either exogenous chemical exposure and/or endogenous agents. In an effort to explain the different types and levels of DNA adducts formed in the context of individual susceptibility to cancer, we have focused on gene-environment interactions. Here, we report on the levels of hydrophobic aromatic amines (AAs), specifically those derived from 4-aminobiphenyl (ABP), and DNA adducts associated with oxidative stress in human pancreas. Although these adducts have been reported in several human tissues by different laboratories, a comparison of the levels of these adducts in the same tissue samples has not been performed. Using the same DNA, the genotypes were determined for N-acetyltransferase 1 (NAT1), the glutathione S-transferase (GST) M1, GSTP1, GSTT1, and NAD(P)H quinone reductase-1 (NQO1) as possible modulators of adduct levels because their gene products are involved in the detoxification of AAs, lipid peroxidation products and in redox cycling. These results indicate that ABP-DNA adducts, malondialdehyde-DNA adducts, and 8-oxo-2'-deoxyguanosine (8-oxo-dG) adducts are present at similar levels. Of the metabolic genotypes examined, the presence of ABP-DNA adducts was strongly associated with the putative slow NAT1*4/*4 genotype, suggesting a role for this pathway in ABP detoxification.

Development of an antipeptide antibody that binds to the C-terminal region of human CYP1B1

An antipeptide antibody was raised against a 14-mer synthetic peptide (CDFRANPNEPA KMN) corresponding to the amino acid sequence from 491 to 504 of human cytochrome P-450 (CYP)1B1. Rabbit-derived antisera demonstrated the ability to induce moderately high antibody titers (>1:10(5)) as judged by enzyme-linked immunosorbent assay. In Western blot analysis, the purified antibody recognized a single protein band (estimated as 56 kDa) in microsomes prepared from human and rodent tissues. No significant cross-reactivity to either human CYP1A1 or human CYP1A2 protein was detected. Titration studies using recombinant human CYP1B1 and an enhanced chemiluminescence-based detection method demonstrated a minimal detection sensitivity for this antiserum at about 0.34 ng/band in 8 x 7-cm minigels. The immunoprecipitation and immunoinhibition results indicate that this antisera recognizes the nondenatured human CYP1B1 protein but does not inhibit its enzyme activity. Using this antibody, CYP1B1 protein was detected in nine different human tissues and in cultured cells induced by various chemicals. This highly specific, highly sensitive antibody provides an important tool to study tissue distribution and cellular expression levels of CYP1B1, with negligible cross-reactivity from the other members of the CYP1 family.

Susceptibility to esophageal cancer and genetic polymorphisms in glutathione S-transferases T1, P1, and M1 and cytochrome P450 2E1

Genetic polymorphisms in enzymes involved in carcinogen metabolism have been shown to influence susceptibility to cancer. Cytochrome P450 2E1 (CYP2E1) is primarily responsible for the bioactivation of many low molecular weight carcinogens, including certain nitrosamines, whereas glutathione S-transferases (GSTs) are involved in detoxifying many other carcinogenic electrophiles. Esophageal cancer, which is prevalent in China, is hypothesized to be related to environmental nitrosamine exposure. Thus, we conducted a pilot case-control study to examine the association between CYP2E1, GSTM1, GSTT1, and GSTP1 genetic polymorphisms and esophageal cancer susceptibility. DNA samples were isolated from surgically removed esophageal tissues or scraped esophageal epithelium from cases with cancer (n = 45), cases with severe epithelial hyperplasia (n = 45), and normal controls (n = 46) from a high-risk area, Linxian County, China. RFLPs in the CYP2E1 and the GSTP1 genes were determined by PCR amplification followed by digestion with RsaI or DraI and Alw26I, respectively. Deletion of the GSTM1 and GSTT1 genes was examined by a multiplex PCR. The CYP2E1 polymorphism detected by RsaI was significantly different between controls (56%) and cases with cancer (20%) or severe epithelial hyperplasia (17%; P < 0.001). Persons without the RsaI variant alleles had more than a 4-6-fold risk of developing severe epithelial hyperplasia (adjusted odds ratio, 6.0; 95% confidence interval, 2.3-16.0) and cancer (adjusted odds ratio, 4.8; 95% confidence interval, 1.8-12.4). Polymorphisms in the GSTs were not associated with increased esophageal cancer risk. These results indicate that CYP2E1 may be a genetic susceptibility factor involved in the early events leading to the development of esophageal cancer.

Expression of calcitonin gene-related peptide (CGRP) mRNA in rat lymphocytes

We recently found that calcitonin gene-related peptide (CGRP)-like immunoreactivity was present in lymphocytes of rat thymus and lymph node. In order to investigate whether these cells were capable of synthesizing CGRP, CGRP mRNA of rat dorsal root ganglia, thymocytes and mesenteric lymph node lymphocytes were determined by reverse transcription and polymerase chain reaction (RT-PCR) utilizing synthetic oligonucleotides bracketing a portion of the calcitonin/CGRP gene. A discrete band of the expected size of 90 base pairs was found in the dorsal root ganglia (positive control), and in both thymocytes and mesenteric lymph node lymphocytes. These data strongly suggest that CGRP is not only an important neuropeptide, but it is also synthesized in lymphocytes of both thymus and lymph nodes, which is identical to that in sensory neurons. CGRP from lymphocytes may act as an immunomodulator and serve as a common ligand in immune and nervous systems.

[In vitro analysis of cross immunoreaction between CGRP and endotoxin in CGRP radioimmunoassay]

In the present study, the effect of endotoxin on the radioimmunoassay of calcitonin gene-related peptide (CGRP) was investigated by method of radioimmunoassay. The results showed a competitive combination of endotoxin at high-concentrations (higher than 5 micrograms/ml) with multiclonal antibody of CGRP, and the cross immunoreaction ratio between CGRP and endotoxin was 5.6 x 10(-6). The mixed endotoxin in samples was effectively cleared through C18 column purification. The data indicated that endotoxin interfered CGRP radioimmunoassay in vitro at high concentrations. The influence of endotoxin on CGRP radioimmunoassay can be avoided through C18 column purification for the endotoxin-containing samples.

Stable expression of human cytochrome P450 1B1 in V79 Chinese hamster cells and metabolically catalyzed DNA adduct formation of dibenzo[a,l]pyrene

Chinese hamster V79 cell lines were constructed for stable expression of human cytochrome P450 1B1 (P450 1B1) in order to study its role in the metabolic activation of chemicals and toxicological consequences. The new V79 cell lines were applied to studies on DNA adduct formation of the polycyclic aromatic hydrocarbon (PAH) dibenzo[a,l]pyrene (DB[a,l]P). This compound has been found to be an environmental pollutant, and in rodent bioassays it is the most carcinogenic PAH yet discovered. Activation of DB[a,l]P in various metabolizing systems occurs via fjord region DB[a,l]P-11, 12-dihydrodiol 13,14-epoxides (DB[a,l]PDE): we found that DB[a,l]P is stereoselectively metabolized in human mammary carcinoma MCF-7 cells to the (-)-anti- and (+)-syn-DB[a,l]PDE which both bind extensively to cellular DNA. To follow up this study and to relate specific DNA adducts to activation by individual P450 isoforms, the newly established V79 cells stably expressing human P450 1B1 were compared with those expressing human P450 1A1. DNA adduct formation in both V79 cell lines differed distinctively after incubation with DB[a,l]P or its enantiomeric 11,12-dihydrodiols. Human P450 1A1 catalyzed the formation of DB[a,l]PDE-DNA adducts as well as several highly polar DNA adducts as yet unidentified. The proportion of these highly polar adducts to DB[a,l]PDE adducts was dependent upon both the concentration of DB[a,l]P and the time of exposure. In contrast, V79 cells stably expressing human P450 1B1 generated exclusively DB[a,l]PDE-DNA adducts. Differences in the total level of DNA binding were also observed. Exposure to 0.1 microM DB[a,l]P for 6 h caused a significantly higher level of DNA adducts in V79 cells stably expressing human P450 1B1 (370 pmol/mg of DNA) compared to those with human P450 1A1 (35 pmol/mg of DNA). A 4-fold higher extent of DNA binding was catalyzed by human P450 1B1 (506 pmol/mg of DNA) compared to human P450 1A1 (130 pmol/mg of DNA) 6 h after treatment with 0.05 microM (-)-(11R,12R)-dihydrodiol. In cells stably expressing human P450 1B1 the DNA adducts were derived exclusively from the (-)-anti-DB[a,l]PDE. These results indicate that human P450 1B1 and P450 1A1 differ in their regio- and stereochemical selectivity of activation of DB[a,l]P with P450 1B1 forming a higher proportion of the highly carcinogenic (-)-anti-(11R, 12S,13S,14R)-DB[a,l]PDE metabolite.

[Modulatory action of alpha 2-adrenoceptor on calcitonin gene-related peptide release from rat mesenteric arterial bed]

The release of calcitonin gene-related peptide (CGRP) from peripheral terminals of sensory nerves was modulated via multiple mechanisms. In the present study, pharmacological agents were used to investigate the modulatory action of alpha 2-adrenoceptor on endotoxin-induced CGRP release from isolated perfused rat mesenteric arterial bed. The results showed that UK14304 (3 x 10(-6) mol/L), a potent alpha 2-adrenoceptor agonist, significantly inhibited both basal and endotoxin-induced CGRP release by 22%-42%, while specific antagonist of alpha 2-adrenoceptor yohimbine (10(-5) mol/L) blocked the effect of UK14304 completely. The data suggest that presynaptic alpha 2-adrenoceptor has an inhibitory effect on basal and endotoxin-induced CGRP release. Dysfunction of alpha 2-adrenoceptor in the late stage of endotoxic shock may be involved in the excess release of CGRP from the peripheral nerves.

Genetic polymorphisms in human liver phenol sulfotransferases involved in the bioactivation of N-hydroxy derivatives of carcinogenic arylamines and heterocyclic amines

Three related forms of phenol sulfotransferase (PSULT), thermostable ST1A2 (SULT1A2hum) and ST1A3 (SULT1A1hum) and a thermolabile TL-PST (SULT1A3hum), are known to exist in human livers. Thermostable forms, whose activities are polymorphically distributed, have been shown to mediate the bioactivation of carcinogenic N-hydroxy arylamines and heterocyclic amines. To clarify the nature of the sulfation polymorphism, the study compared the expressed levels of ST1A2, ST1A3 and TL-PST mRNAs in human livers by the method of reverse-transcriptase polymerase chain reaction (RT-PCR), utilizing HindIII, BamHI and SnaBI sites which were unique to the above PSULT cDNAs, respectively. Of the PCR products derived from human liver (n = 26), 43-89, < 1-29 and < 1-21% showed the restriction pattern characteristic for ST1A3, ST1A2 and TL-PST cDNAs, respectively, thus indicating that ST1A3 mRNA is the major transcript. Hepatic p-nitrophenol and dopamine sulfation rates ranged from 440-2670 and < 5-460 pmol/min per mg protein in the 26 individuals, respectively. The observed differences in the ST1A3 and TL-PST mRNA levels were consistent with the differences in p-nitrophenol and dopamine sulfations. Relative levels of hepatic ST1A3 mRNA were non-normally distributed and correlated significantly with p-nitrophenol sulfation. In addition, variant forms of ST1A3 mRNA encoding Arg213His and Met223Val were detected in human livers. With regard to Arg213His, 28 individuals who had homozygous 213Arg alleles, 15 individuals who were heterozygotes and nine homozygous 213His individuals were found by a newly established genotyping method among 52 human liver samples. Frequency of 223Val allele was apparently lower than that of 213His allele, as no homozygous 223Val individual and only three individuals who were heterozygotes (223Met/Val) were observed among 52 individuals. These results suggest that regulation of p-nitrophenol sulfation occurs at the level of gene transcription of ST1A3 which is the major transcript of the three PSULT mRNAs and that a polygenic basis for the apparent genetic polymorphism of sulfation was likely because of the existence of ST1A3 variants.

[Changes of CGRP levels in plasma and CGRP mRNA in dorsal root ganglia during endotoxicosis in the rat]

To investigate the changes of both CGRP release and synthesis during endotoxicosis, CGRP mRNA in thoracolumbar dorsal root ganglia (DRG) was determined by the semi-quantity RT-PCR and the CGRP levels in plasma were measured by RIA. The results showed that plasma CGRP, but not mRNA, began to increase 30 min after endotoxin (5 mg/kg, i.v.) administration. On the other hand, the CGRP levels in plasma and CGRP mRNA in DRG were significantly increased by 142% and 32% respectively at the 3 h of injection and by 216% and 85% respectively at the 8 h of injection. The data suggest that not only the release of CGRP from the peripheral organs, but also the transcription of CGRP mRNA and synthesis of CGRP in sensory neurons are increased during the development of endotoxicosis in the rat. Presumably the DRG is an important source of CGRP release in the response to endotoxicosis.

[Effects of inflammatory mediators on the release of CGRP from isolated mesenteric arterial bed of rat]

The purpose of the present study was to observe whether inflammatory mediators, such as: Prostaglandin E2 (PGE2), Bradykinin (BK), Histamine (HIS), Platelet active factor (PAF) and 5-hydroxytryptamine (5-HT), directly triggered the release of CGRP from perivascular nerves in isolated rat mesenteric arterial bed. The results showed that PGE2 (1-100 mumol/L) and BK (5-10 mumol/L) caused time- and concentration-dependent CGRP release, but HIS, PAF and 5-HT did not show significant effects. Our data indicate that PGE2 and BK are the major inflammatory mediators in triggering the release of CGRP from the perivascular CGRP-containing nerve.