Differentiation of Low- and High-Grade Gliomas Using High b-Value Diffusion Imaging with a Non-Gaussian Diffusion Model

BACKGROUND AND PURPOSE

Imaging-based tumor grading is highly desirable but faces challenges in sensitivity, specificity, and diagnostic accuracy. A recently proposed diffusion imaging method by using a fractional order calculus model offers a set of new parameters to probe not only the diffusion process itself but also intravoxel tissue structures, providing new opportunities for noninvasive tumor grading. This study aimed to demonstrate the feasibility of using the fractional order calculus model to differentiate low- from high-grade gliomas in adult patients and illustrate its improved performance over a conventional diffusion imaging method using ADC (or D).

MATERIALS AND METHODS

Fifty-four adult patients (18-70 years of age) with histology-proved gliomas were enrolled and divided into low-grade (n = 24) and high-grade (n = 30) groups. Multi-b-value diffusion MR imaging was performed with 17 b-values (0-4000 s/mm(2)) and was analyzed by using a fractional order calculus model. Mean values and SDs of 3 fractional order calculus parameters (D, β, and μ) were calculated from the normal contralateral thalamus (as a control) and the tumors, respectively. On the basis of these values, the low- and high-grade glioma groups were compared by using a Mann-Whitney U test. Receiver operating characteristic analysis was performed to assess the performance of individual parameters and the combination of multiple parameters for low- versus high-grade differentiation.

RESULTS

Each of the 3 fractional order calculus parameters exhibited a statistically higher value (P ≤ .011) in the low-grade than in the high-grade gliomas, whereas there was no difference in the normal contralateral thalamus (P ≥ .706). The receiver operating characteristic analysis showed that β (area under the curve = 0.853) produced a higher area under the curve than D (0.781) or μ (0.703) and offered a sensitivity of 87.5%, specificity of 76.7%, and diagnostic accuracy of 82.1%.

CONCLUSIONS

The study demonstrated the feasibility of using a non-Gaussian fractional order calculus diffusion model to differentiate low- and high-grade gliomas. While all 3 fractional order calculus parameters showed statistically significant differences between the 2 groups, β exhibited a better performance than the other 2 parameters, including ADC (or D).

A Diffusion Tensor Imaging Study on White Matter Abnormalities in Patients with Type 2 Diabetes Using Tract-Based Spatial Statistics

BACKGROUND AND PURPOSE

Patients with type 2 diabetes mellitus have considerably higher risk of developing cognitive impairment and dementia. WM changes in these patients have been reported. Our aim was to demonstrate that gradual and continuous WM change and the associated cognitive decline in patients with type 2 diabetes mellitus can be captured by DTI parameters, which can be used to complement neuropsychological test scores in identifying patients with type 2 diabetes mellitus with and without mild cognitive impairment.

MATERIALS AND METHODS

Forty-two patients with type 2 diabetes mellitus, divided into a group with mild cognitive impairment (n = 20) and a group with normal cognition (n = 22), were enrolled with age-, sex-, and education-matched healthy controls (n = 26). 3T DTI followed by Tract-Based Spatial Statistics analysis was used to investigate the differences in fractional anisotropy, mean diffusivity, axial diffusivity (λ1), and radial diffusivity (λ23) among the groups. A receiver operating characteristic analysis assessed the performance of DTI parameters for separating the 2 groups with type 2 diabetes mellitus.

RESULTS

The whole-brain Tract-Based Spatial Statistics analysis revealed that 7.3% and 24.9% of the WM exhibited decreased fractional anisotropy and increased mean diffusivity (P < .05), respectively, between the diabetes mellitus with mild cognitive impairment and the diabetes mellitus with normal cognition groups, while considerably larger WM regions showed fractional anisotropy (36.6%) and mean diffusivity (58.8%) changes between the diabetes mellitus with mild cognitive impairment and the healthy control groups. These changes were caused primarily by an elevated radial diffusivity observed in the patients with diabetes mellitus with mild cognitive impairment. Radial diffusivity also exhibited subtle but statistically significant changes between the diabetes mellitus with normal cognition and the healthy control groups. Analyses on individual fiber tracts showed pronounced fractional anisotropy reduction and mean diffusivity elevation in regions related to cognitive functions. The receiver operating characteristic analysis on the right cingulum (hippocampus) showed that fractional anisotropy produced a larger area under the curve (0.832) than mean diffusivity (0.753) for separating mild cognitive impairment from normal cognition among patients with type 2 diabetes mellitus. When fractional anisotropy was combined with mean diffusivity, the area under the curve was further improved to 0.857.

CONCLUSIONS

DTI parameters can show a substantial difference between patients with type 2 diabetes mellitus with and without mild cognitive impairment, suggesting their potential use as an imaging marker for detecting cognitive decline in patients with type 2 diabetes mellitus. More important, DTI parameters may capture gradual and continuous WM changes that can be associated with early stages of cognitive decline in patients with type 2 diabetes mellitus before they can be diagnosed clinically by using conventional neuropsychological tests.

Decreased interhemispheric functional coordination underlying the cognitive impairment in late-onset depression

Background

The intuitive association between cognitive dysfunction in late onset depression (LOD) and the aberrant functional activity in the brain's default-mode network (DMN) has prompted interest in exploring the role of the DMN in LOD. The altered pattern of resting state voxel-mirrored homotopic connectivity (VMHC) in cognitive processes is not yet well understood in LOD.

Methods

The study was designed to examine the implicit coupling between the alteration of interhemispheric functional coordination and cognitive impairment in LOD. Thirty-one LOD patients and 37 matched healthy controls (HC) underwent neuropsychological tests and functional magnetic resonance imaging (fMRI) in this study.

Results

Compared to HC group, attenuated VMHC in superior frontal gyrus, superior temporal gyrus, posterior cerebellar lobe, postcentral and precentral gyrus was observed in LOD. Neuro-behavioral relevancy approach revealed that the imbalanced interhemispheric functional coordination in bilateral cerebellum was positively correlated with the performance of trail making test in LOD (r = 0.367, P = 0.040).

Conclusion

Altered linkage pattern of intrinsic homotopic connectivity and cognition was firstly investigated in LOD, and it would provide a novel clue to reveal the neural substrates underlying the cognitive dysfunction in LOD.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Mutation analysis of four Chinese families with pure hereditary spastic paraplegia: pseudo- X-linked dominant inheritance and male lethality due to a novel ATL1 mutation

We studied four Chinese families with pure hereditary spastic paraplegia (HSP) to investigate the clinical features and associated genetic mutations. Linkage analysis was performed for all families to map the disease locus onto autosomal chromosomes, and related loci involved in HSP on the X chromosome were also examined. Polymerase chain reaction (PCR) sequencing was used to detect gene mutations. To confirm the influence of a splice-site mutation on mRNA, we used reverse transcription-PCR and direct sequencing. Linkage analysis and ATL1 gene sequencing of amniocytes were performed for prenatal genetic diagnosis. One missense variant (c.1517T>A) and a splice-site mutation (c.1245+1G>A) in SPAST, and two missense variants (c.715C>T, c.1204T>G) in ATL1 were identified. The c.1245+1G>A mutation caused a deletion of exon 9 in the SPAST gene. Prenatal genetic diagnosis showed that fetus did not carry the ALT1 c.1204T>G mutation. Follow-up was maintained for 5 years, and the negative result was confirmed by evidence of a healthy growing boy. We identified two novel mutations and two previously reported mutations in SPAST and ATL1, respectively. The family with the ATL1 c.1204T>G mutation exhibited male-lethality, female infancy-onset, and pseudo- X-linked dominant transmission, which had never been previously reported for HSP. Characteristic facial features were also noticed. The boy on whom prenatal gene diagnosis was performed is healthy and without unusual facies, suggesting that the c.1204T>G mutation might be related to these features. The results extend the genetic spectrum of HSP and suggest that linkage analysis remains a powerful tool in gene discovery studies.

Closing Domestic Nutrient Cycles Using Microalgae

This study demonstrates that microalgae can effectively recover all P and N from anaerobically treated black water (toilet wastewater). Thus, enabling the removal of nutrients from the black water and the generation of a valuable algae product in one step. Screening experiments with green microalgae and cyanobacteria showed that all tested green microalgae species successfully grew on anaerobically treated black water. In a subsequent controlled experiment in flat-panel photobioreactors, Chlorella sorokiniana was able to remove 100% of the phosphorus and nitrogen from the medium. Phosphorus was depleted within 4 days while nitrogen took 12 days to reach depletion. The phosphorus and nitrogen removal rates during the initial linear growth phase were 17 and 122 mg·L(-1)·d(-1), respectively. After this initial phase, the phosphorus was depleted. The nitrogen removal rate continued to decrease in the second phase, resulting in an overall removal rate of 80 mg·L(-1)·d(-1). The biomass concentration at the end of the experiment was 11.5 g·L(-1), with a P content of approximately 1% and a N content of 7.6%. This high algal biomass concentration, together with a relatively short P recovery time, is a promising finding for future post-treatment of black water while gaining valuable algal biomass for further application.

Abstract P4-05-12: MultiOmyx™ screening for prognostic indicators of breast cancer

Over the last three decades, the incidence of early-stage breast cancer has doubled while the incidence of late stage breast cancer has slightly decreased; however, the standard treatment for both has not changed significantly in the last 10 years. Of those diagnosed with early-stage breast cancer, 30% will develop recurrent disease, though there is currently no diagnostic available to identify these cases. Conversely, identifying late stage patients with a low- risk for recurrence could spare them from post-surgical chemotherapy. We have developed a technology that allows in situ staining and analysis of up to 60 proteins on a single tissue slide. In this exploratory study we evaluated 25 known biomarkers on a cohort of more than 800 breast cancer cases assembled onto three tissue arrays. The cohort spans clinical grades and breast cancer subtypes, and is thus useful in novel associations of biomarker expression across a variety of clinical features. Twenty-five markers were chosen based on literature reports for marker association with disease recurrence and represent a range of biological features including signaling pathways and cell phenotypes. The slides were sequentially stained with antibodies that were directly conjugated to Cy3 and Cy5 dyes, imaged, evaluated for quality and subject inclusion, and subsequently analyzed for statistical correlations of expression values to clinical features. The images were then processed using a single cell analysis algorithm which allows for quantification of individual tumor cells and signal intensities for the markers to be extracted from sub-cellular domains (nucleus, cytoplasm, and membrane of each cell) allowing unique patterns of protein expression to be determined. Univariate Cox proportional hazards analysis was first applied to determine those features with strongest association with ‘death due to disease’. Of the 25 markers analyzed, several markers (e.g. API3, AMPH2, beta-catenin, CD44, CEACAM5, CK15, CK19, cMET, Her2, Ki67, TRIM29) were found to have strong association with poor outcome (FDR &lt; 0.05). After adjusting for clinical variables (stage, number of positive nodes, grade), a number of markers (e.g. CD44, CEACAM5, cMET, TRIM29) still show a strong association with poor clinical outcome (FDR &lt; 0.05, Cox proportional hazards model). CEACAM5 is part of the MammostratTM panel of markers used for determining prognosis in ER positive breast cancers after Tamoxifen® treatment. CD44, a cancer stem cell marker, and TRIM 29, a transcriptional regulatory factor involved in carcinogenesis, have been associated with basal-like breast cancers which have the worst prognosis of all the breast cancer subtypes. High levels of cMET have been associated with poor prognosis for all breast cancer subtypes and cMET is being explored as a therapeutic target. The MultiomyxTM methodology enabled us to verify a subset of biomarkers that are clinically relevant to breast cancer outcome. Using this technology could lead to identification of novel biosignatures that stratify patients and enable precision medicine that results in better treatment decisions and prognosis for patients.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P4-05-12.

Three-dimensional dynamics of oblate and prolate capsules in shear flow

We study computationally the dynamics of oblate and prolate spheroidal capsules in simple shear flow with small inertia for a range of dimensionless shear rates. The capsule is modelled as a liquid droplet enclosed by a hyperelastic membrane, and its equatorial plane is initially tilted out of the plane of shear. We find, at low shear rates, the well-accepted tumbling motion is not always stable for both oblate and prolate capsules. For an oblate capsule, the dominant stable modes for increasing dimensionless shear rate are as follows: rolling with the equatorial plane staying in the plane of shear, precessing following Jeffery's orbit [Proc. R. Soc. London A 102, 161 (1922)], and tumbling. Interestingly, the order of modes is reversed for a prolate capsule: tumbling, precessing, and rolling with increasing dimensionless shear rate. At transitional regimes, we find the stable motion of a capsule can depend on its initial titled angle, even at the same shear rate. At high dimensionless shear rates, a spheroidal capsule undergoes a complicated oscillating-swinging motion: Its major axis oscillates about the plane of shear in addition to the swinging about a mean angle with flow direction found previously, and the amplitudes of both oscillations decrease when increasing the dimensionless shear rate towards a steady tank treading motion asymptotically. We summarize the results in phase diagrams and discuss the reorientation of both oblate and prolate capsules in a wide range of dimensionless shear rates.

Detrusor botulinum toxin A injection significantly decreased urinary tract infection in patients with traumatic spinal cord injury

STUDY DESIGN

The study was designed as a single-arm clinical trial.

OBJECTIVES

To investigate the effect of detrusor botulinum toxin A (BoNTA) injection on urinary tract infection (UTI) in patients with spinal cord injury (SCI).

SETTING

The study was performed in a national rehabilitation research center of China.

METHODS

Between September 2010 and May 2012, 41 male inpatients with neurogenic detrusor overactivity (NDO) caused by traumatic SCI, mean age 36.0±8.8 years, duration of SCI since inclusion 21.5±17.3 months, received an injection of 300 U BoNTA into detrusor. Before and 3 months after injection, each patient kept a bladder diary, underwent video-urodynamic investigation and urine culture. All UTIs occurring in the 6 months before and the 6 months after injection were recorded.

RESULTS

Before injection, the mean number of UTI over 6 months was 1.39±1.36. After injection, the mean significantly decreased to 0.78±0.96 (P=0.023). The mean maximum detrusor pressure during filling decreased significantly in the patients of detrusor overactivity (n=24) compared with patients of normo-active detrusor (n=17) after injection (35.4±12.2 vs 20.9±7.9 cmH(2)O, P=0.000), meantime, the decrease of UTI was significant in the former (1.29±1.21 vs 0.41±0.62 cmH(2)O, P=0.015) while no significant in the latter (1.46±1.47 vs 1.04±1.08, P=0.319).

CONCLUSION

Detrusor BoNTA injection significantly decreased UTI in SCI patients with NDO. This effect seems to be related to the decrease of detrusor pressure.

Numerical simulations of deformation and aggregation of red blood cells in shear flow

This article reviews numerical simulations of red blood cells (RBCs) mainly using the lattice Boltzmann method (LBM), focusing on the 2-dimensional deformation and aggregation of the cells in simple shear flow. We outline the incorporation of the immersed boundary method into the LBM, in which the membrane forces are obtained from the membrane model. The RBCs are simulated as a single biconcave capsule and as a doublet of biconcave capsules. The transition from swinging to tumbling motions of the RBCs, as induced by reducing the shear rate or increasing the membrane bending stiffness, is discussed. Also discussed is the aggregation tendency of the doublet of RBCs, for which homogenous deformability maintained RBC aggregation, whereas an increased deformability difference resulted in RBC dissociation.

A systematic review on use of Chinese medicine and acupuncture for treatment of obesity

Obesity is a major health hazard and despite lifestyle modification, many patients frequently regain any lost body weight. The use of western anti-obesity drugs has been limited by side effects including mood changes, suicidal thoughts, and gastrointestinal or cardiovascular complications. The effectiveness and safety of traditional Chinese medicine including Chinese herbal medicine (CHM) and acupuncture provide an alternative established therapy for this medical challenge. In this systematic review, we used standard methodologies to search, review, analyse and synthesize published data on the efficacy, safety and relapse of weight regain associated with use of CHM and acupuncture. We also examined the rationale, mechanisms and potential utility of these therapies. A total of 12 electronic databases, including Chinese, English, Korean and Japanese, were searched up to 28 February 2010. Randomized controlled trials (RCTs) for CHM and/or acupuncture with comparative controls were considered. We used the Jadad scale to assess methodological qualities, the random effect model in the pooled analysis of therapeutic efficacy to adjust for heterogeneity and funnel plots to explore publication bias. After screening 2,545 potential articles from the electronic databases, we identified 96 RCTs; comprising of 49 trials on CHM treatment, 44 trials on acupuncture treatment and 3 trials on combined therapy for appraisal. There were 4,861 subjects in the treatment groups and 3,821 in the control groups, with treatment duration ranging from 2 weeks to 4 months. Of the 77 publications written in Chinese, 75 had a Jadad score <3, while 16 of the 19 English publications had a Jadad score of >3. Efficacy was defined as body weight reduction ≥ 2 kg or body mass index (BMI) reduction ≥ 0.5 kg/m(2) . Compared with placebo or lifestyle modification, CHM and acupuncture exhibited respective 'risk ratio' (RR) of 1.84 (95% CI: 1.37-2.46) and 2.14 (95% CI: 1.58-2.90) in favour of body weight reduction, with a mean difference in body weight reduction of 4.03 kg (95% CI: 2.22-5.85) and 2.76 kg (95% CI: 1.61-3.83) and a mean difference in BMI reduction of 1.32 kg m(-2) (95% CI: 0.78-1.85) and 2.02 kg m(-2) (95% CI: 0.94-3.10), respectively. Compared with the pharmacological treatments of sibutramine, fenfluramine or orlistat, CHM and acupuncture exhibited an RR of 1.11 (95% CI: 0.96-1.28) and 1.14 (95% CI: 1.03-1.25) in body weight reduction, mean difference in body weight reduction of 0.08 kg (95% CI: -0.58 to 0.74) and 0.65 kg (95% CI: -0.61 to 1.91), and mean difference in BMI reduction of 0.18 kg m(-2) (95% CI: -0.39 to 0.75) and 0.83 kg m(-2) (95% CI: 0.29-1.37), respectively. There were fewer reports of adverse effects and relapses of weight regain in CHM intervention studies conducted in China than studies conducted outside China. CHM and acupuncture were more effective than placebo or lifestyle modification in reducing body weight. They had a similar efficacy as the Western anti-obesity drugs but with fewer reported adverse effects. However, these conclusions were limited by small sample size and low quality of methodologies.

Potential risk of zoonotic transmission from young swine to human: seroepidemiological and genetic characterization of hepatitis E virus in human and various animals in Beijing, China

The aim of this study was to further investigate the prevalence of infection and genotype of hepatitis E virus (HEV) among different species of animals, people whose works are related to pigs and the general population in the suburb of Beijing, China. Serum and faecal samples were collected from 10 animal species and humans. Anti-HEV was detected by enzyme immunoassays (EIA); HEV RNA was amplified by reverse transcription-nested polymerase chain reaction (RT-nPCR) method. PCR products were cloned and sequenced. The isolated swine HEV sequences were analysed phylogenetically. The positive rates of serum anti-HEV in swine, cattle, milk cow, horse, sheep, donkey, dog, duck, chicken, pig farm workers and slaughterhouse workers, and general population were 81.17% (802/988), 25.29% (66/261), 14.87% (40/269), 14.29% (40/280), 9.30% (53/514), 0 (0/25), 0 (0/20), 2.53% (8/316), 3.03% (7/231), 58.73% (37/63), 35.87% (66/184) and 20.06% (538/2682), respectively. The anti-HEV prevalence in adult swine (≥ 6 months) and younger swine (≤ 3 months) was 91.49% (591/646) and 61.7% (211/342), respectively. The positive rate of HEV RNA in young swine faeces was 47.94% (93/194). All 93 isolates from the younger swine shared 87.8-100% nucleotide homology with each other and had identities of 75.6-78.9%, 73.9-76.1%, 76.4-80.6% and 83.1-95.0% with the corresponding regions of genotypes 1-4 HEV, respectively. Phylogenetic analysis showed that all HEV isolates belong to genotype 4, subgenotype 4d. These results suggest a potential risk of zoonotic transmission of HEV from younger swine to farmers who rear pigs.

Transition from orbital liquid to Jahn-Teller insulator in orthorhombic perovskites RTiO3

Following the same strategy used for RVO3, thermal conductivity measurements have been made on a series of single-crystal perovskites RTiO3 (R=La,Nd,...,Yb). Results reveal explicitly a transition from an orbital liquid to an orbitally ordered phase at a magnetic transition temperature, which is common for both the antiferromagnetic and ferromagnetic phases in the phase diagram of RTiO3. This spin/orbital transition is consistent with the mode softening at T_{N} in antiferromagnetic LaTiO3 and is supported by an anomalous critical behavior at T_{c} in ferromagnetic YTiO3.

Tank-treading, swinging, and tumbling of liquid-filled elastic capsules in shear flow

The dynamic motion of three-dimensional (3D) capsules in a shear flow is investigated by direct numerical simulation. The capsules are modeled as Newtonian liquid droplets enclosed by elastic membranes, with or without considering the membrane-area incompressibility. The internal liquid of the capsules is the same as that outside. The dynamic motion of capsules with initially spherical and oblate spheroidal unstressed shapes is studied under various shear rates. The results show that spherical capsules deform to stationary configurations and then the membranes rotate around the liquid inside (steady tank-treading motion). Such a steady mode is not observed for oblate spheroidal capsules. It is shown that with the shear rate decreasing, the motion of oblate spheroidal capsules changes from the swinging mode (a capsule undergoes periodic shape deformation and inclination oscillation while its membrane is rotating around the liquid inside) to tumbling mode.

Pancreatic islet beta-cell deficit and glucose intolerance in rats with uninephrectomy

This study was performed to examine the effect of chronic renal impairment and renin-angiotensin system (RAS) activation induced by unilateral nephrectomy (UNX) on the development of pancreatic islet beta-cell deficit and glucose intolerance. Sprague-Dawley rats were randomized into three groups: untreated UNX (n=10), UNX treated with the angiotensin-converting enzyme inhibitor lisinopril (n=8) and sham operation (n=10). Blood glucose, serum insulin, renal function and histological changes of kidney and pancreas were examined 8 months postoperation. Compared with the sham rats, UNX rats developed renal impairment, insulin deficiency and glucose intolerance. Histological staining revealed an islet beta-cell deficit associated with increased immunoreactivity for angiotensin and angiotensin type 1 receptor in UNX rats. Treatment with lisinopril significantly improved renal dysfunction, hyperglycemia, insulin secretion and islet RAS expression. These data suggest that chronic renal impairment and RAS activation may contribute to islet beta-cell loss and glucose intolerance. RAS blockade may therefore prevent these disorders.

Orbital fluctuations and orbital flipping in RVO3 perovskites

The effect of the average R-site ionic radius IR and variance on the orbital and magnetic order in R3+-doped YVO3 was studied in Y1-xLaxVO3 and Y1-x(La0.2337Lu0.7663)xVO3 with fixed IR. The orbital flipping temperature T{CG} increases nonlinearly with increasing R-site variance, indicating that the V-O-V bond angle is not the primary driving force stabilizing the C-type orbitally ordered phase. The suppressed thermal conductivity in the G-type orbitally ordered phase signals some remaining orbital randomness that is enhanced by t{2} and et hybridization in {3}T{1g} site symmetry.

Transient deformation of elastic capsules in shear flow: effect of membrane bending stiffness

The transient deformation of liquid capsules enclosed by elastic membranes with bending rigidity in shear flow has been studied numerically, using an improved immersed boundary-lattice Boltzmann method. The purpose of the present study is to investigate the effect of interfacial bending stiffness on the deformation of such capsules. Bending moments, accompanied by transverse shear tensions, usually develop due to a preferred membrane configuration or its nonzero thickness. The present model can simulate flow induced deformation of capsules with arbitrary resting shapes (concerning the in-plane tension) and arbitrary configurations at which the bending energy has a global minimum (minimum bending-energy configurations). The deformation of capsules with initially circular, elliptical, and biconcave resting shapes was studied; the capsules' minimum bending-energy configurations were considered as either uniform-curvature shapes (like circle or flat plate) or their initially resting shapes. The results show that for capsules with minimum bending-energy configurations having uniform curvature (circle or flat plate), the membrane carries out tank-treading motion, and the steady deformed shapes become more rounded if the bending stiffness is increased. For elliptical and biconcave capsules with resting shapes as minimum bending-energy configurations, it is quite interesting to find that with the bending stiffness increasing, the capsules' motion changes from tank-treading mode to flipping mode, and resembles Jeffery's flipping mode at large bending stiffness.

Gene amplification and associated loss of 5' regulatory sequences of CoAA in human cancers

CoAA is an RRM-containing transcriptional coactivator that stimulates transcriptional activation and regulates alternative splicing. We show that the CoAA gene is amplified at the chromosome 11q13 locus in a subset of primary human cancers including non-small cell lung carcinoma, squamous cell skin carcinoma and lymphoma. Analysis of 42 primary tumors suggests that CoAA amplifies independently from the CCND1 locus. Detailed mapping of three CoAA amplicons reveals that the amplified CoAA gene is consistently located at the 5' boundaries of the amplicons. The CoAA coding and basal promoter sequences are retained within the amplicons but upstream silencing sequences are lost. CoAA protein is overexpressed in tumors containing the amplified CoAA gene. RNA dot blot analysis of 100 cases of primary tumors suggests elevated CoAA mRNA expression. CoAA positively regulates its own basal promoter in transfection assays. Thus, gene amplification, loss of silencing sequence and positive feedback regulation may lead to drastic upregulation of CoAA protein. CoAA has transforming activities when tested in soft agar assays, and CoAA is homologous to oncoproteins EWS and TLS, which regulate alternative splicing. These data imply that CoAA may share a similar oncogenic mechanism with oncogene EWS and that CoAA deregulation may alter the alternative splicing of target genes.

Gene therapy by membrane-expressed superantigen for α-fetoprotein-producing hepatocellular carcinoma

Staphylococcus enterotoxin A (SEA) is a powerful immunostimulant, which can stimulate T cells bearing certain T-cell receptor beta-chain variable regions, when bound to major histocompatibility complex II molecules. In vivo administration of intact superantigen in sufficient therapeutic amounts risks unwanted cytotoxicity against normal cells. In this study, we used SEA fused with CD80 transmembrane region (named as SEAtm) driven by alpha-fetoprotein (AFP) enhancer/promoter to reduce toxicity and to improve safety and efficiency in the application of SEA. We demonstrated that SEAtm by adenovirus from the AFP enhancer/promoter (AdAFPSEA) could be expressed on the surface of AFP-producing cell line Hepa1-6 instead of non-AFP-producing cell lines. Hepa1-6 infected by recombinant adenovirus stimulated proliferation of splenocytes and activated CD4(+) and CD8(+) T cells in vitro. After AdAFPSEA was injected into the subcutaneously established hepatoma in vivo, the expression of SEA was detected in tumor tissues, which subsequently induced tumor-specific cytotoxic T cells in spleen. Moreover, hepatocellular carcinoma (HCC) xenografts were suppressed by treatment with AdAFPSEA and the survival time of treated mice was prolonged. These findings suggest that membrane-expressed SEA by adenovirus from AdAFPSEA can generate stronger local and systemic antitumor responses against HCC.

Specific heat of single-crystal PrMnO3

The specific heat of single-crystal PrMnO₃ was investigated from 2 to 200 K under different magnetic fields up to 8 T. A Schottky-like anomaly observed at low temperature was gradually shifted to higher temperatures by magnetic fields. The first four singlets of the Pr^3+ 3H₄ ground multiplet in PrMnO₃ are given for the first time by fitting the specific heat of Pr³⁺ ions below 40 K under zero field. By analysing the field dependence of the first singlet of Pr³⁺ ions, the Pr-Mn exchange field is found to be negligible, which is consistent with the magnetic anisotropy of Pr³⁺ ions revealed in the magnetic measurement. At T_N, the cooperative antiferromagnetic ordering of Mn³⁺ spins shows up as λ-shaped anomaly, which is lowered and broadened in magnetic fields. The magnetic entropy near T_N is estimated by subtracting the contributions to specific heat from Pr³⁺ ions and lattice vibrations. It was found that the fraction of entropy above T_N in the total entropy increases with the fields due to the enhancement of spin fluctuations by magnetic field.

[Influence of staphylococcal enterotoxin A on immunogenicity of hepatocellular carcinoma cells]

OBJECTIVE

To transduce the gene of staphylococcal enterotoxin A (SEA) into a HCC cell line HHCC and to make the cells to express the molecules of SEA for the purpose of improving the immunogenicity and inducing immune rejection of HCC.

METHODS

Construct retroviral vector containing the gene of SEA and transduce it into HHCC cells. Then the integration, transcription and expression of recombinant were analyzed. At last cytotoxicity test of peripheral blood mixed lymphocytes was carried out.

RESULTS

We obtained the retroviral vector pLXSN-SEA, transduced into HHCC cells and obtained the HCC cell line that expressed SEA toxin protein. The content of SEA in supernatant was at the level of pg. The cytotoxicity of HHCC transduced with SEA by T lymphocytes was 45.6%, which was higher than that of HHCC (20.7%). The Km value of T lymphocytes against HHCC transduced with SEA and without SEA was 5.18 x 10(4) and 2.92 x 10(5), separately. The difference had statistical significance.

CONCLUSIONS

After transducing the SEA gene, although tiny quantity of expression is detected, the cytotoxicity assay proves that the expression of SEA lead to a robust immune response.

Reconstruction of SEA-B7.1 double signals on human hepatocellular carcinoma cells and analysis of its immunological effect

Since transfection of established tumors with immunostimulatory genes, such as superantigens (SAg), a family of bacterial and viral proteins with strong immunostimulatory properties, can elicit antitumor immunity, direct transfection of tumors with genes of staphylococcal enterotoxin A (SEA) could probably set up a new way of immunological pathway. In our study, human hepatocellular carcinoma (HCC) cell lines stably transduced with SEA and B7.1/SEA fused genes, HHCCSEA and HHCCBS, were obtained by using the method of retroviral mediated gene transduction. The results showed that human HCC cells could express SEA gene. Although a tiny quantity of expression was detected, a robust immune response was promoted. The cytotoxicity of CTL on HHCCBS was the same as that on HHCCSEA. But the K(m) value of the reaction of the former was lower than that of HHCCSEA. Furthermore, the activity assay of T cells by ELISPOT demonstrated that HHCCBS could elicit more CTL activity than HHCCSEA and HHCCB7.1. It suggested that the affinity of T cells to HHCCBS was higher and the maxim velocity of reaction could be attained at an early stage of the reaction. Transduced HCC cells were also analyzed for HLA expression, and it was found that a majority of the cells expressed HLA-I molecules but no HLA-DR molecules. After blocking the HLA-I molecules by HLA-I mAb, the cytotoxicity of T lymphocytes dropped remarkably. The results suggested that SEA were mainly presented by HLA-I molecules, and that B7.1 and SEA could have synergistic action at the early stage of the reaction, but the relationship between them in the consequent process needs to be clarified.

[A retrospective analysis of therapeutic outcome of various types of severe virus hepatitis]

OBJECTIVE

To explore combined therapeutic schemes for severe virus hepatitis and to raise survival rate.

METHODS

The therapeutic outcomes of different schemes were analyzed in 1020 cases of severe viral hepatitis treated in our hospital in recent twenty years. The treatments were classified as basic and combination of Chinese traditional and Western medicine therapies in which embryonic liver cell suspend liquid or hepatic growth factor, or/and artificial liver as blood cleaner were also used for the latter.

RESULTS

The survival rate was 30.28% (33/109) treated by basic procedures and 60.15% (548/911) by combined procedures. There was obvious statistical difference in survival rate between the two groups (P<0.001). Among all the patients, 219 (21.47%) suffered from acute or sub-acute severe hepatitis, 801 (78.53%) chronic severe hepatitis; 446 started their treatment at the early stage of the disease and the survival rate was 77.13% (344/446); 404 at the mid stage and 170 at the late stage and the survival rates were 52.72% (213/404) and 14.12% (24/170), respectively. The survival rate for the patients treated at the early or the mid stage was much higher than that at the late stage (P<0.001), and had a positive correlation with the activity of prothrombin.

CONCLUSION

The combined therapies used in present study are effective to raise the survival rate of the patients with severe virus hepatitis. Early treatment is extremely important for the patients' prognosis.