A phase II study evaluating the safety and efficacy of an adenovirus-ΔLMP1-LMP2 transduced dendritic cell vaccine in patients with advanced metastatic nasopharyngeal carcinoma

BACKGROUND

Individuals with metastatic Epstein-Barr virus (EBV)-positive nasopharyngeal carcinoma (NPC) continue to have poor outcomes. To evaluate the ability of a dendritic cell (DC) vaccine to target subdominant EBV antigens LMP1 and LMP2 expressed by NPC cells, we vaccinated patients using autologous DCs transduced with an adenovirus encoding a truncated LMP1 (ΔLMP1) and full-length LMP2 (Ad-ΔLMP1-LMP2).

MATERIALS AND METHODS

Sixteen subjects with metastatic NPC received Ad-ΔLMP1-LMP2 DC vaccines i.d. biweekly for up to five doses. Toxicity, immune responses and clinical responses were determined.

RESULTS

Most patients had extensive disease, with a median of three visceral sites of involvement (range 1-7). No significant toxicity was observed. Ad-ΔLMP1-LMP2 DCs induced delayed type hypersensitivity responses in 9 out of 12 patients, but although these DCs activated LMP1/2-specific T cells in vitro, no such increase in the frequency of peripheral LMP1/2-specific T cells was detected. Three patients had clinical responses including one with partial response (for 7½ months) and two with stable disease (for 6½ and 7½ months).

CONCLUSIONS

Ad-ΔLMP1-LMP2 transduced DCs can be successfully generated and safely administered to patients with advanced NPC. Since efficacy was limited, future studies should focus on DC vaccines with greater potency administered to subjects with less tumor burden.

A randomised controlled study of risperidone and olanzapine for schizophrenic patients with neuroleptic-induced acute dystonia or parkinsonism

The objective of this study was to compare the effects of risperidone and olanzapine in schizophrenic patients with intolerant extrapyramidal side effects (EPS) on first generation antipsychotics. We conducted an 8-week, rater-blinded, flexible dose study. Seventy patients with schizophrenia, who met the DSM-IV research criteria of having neuroleptic-induced acute dystonia or parkinsonism, were randomly assigned to risperidone or olanzapine group. The primary outcome was a comparison of the incidence of concomitant anticholinergic drugs usage between the groups to manage their acute dystonia and parkinsonism. The average doses of risperidone and olanzapine from baseline to study end point were 1.8-3.5 mg/day and 7.7-11.7 mg/day, respectively. There were no significant differences in demographic data, severity of EPS or psychotic symptoms between the groups at baseline assessment. Patients taking risperidone had significantly higher incidence of using anticholinergic drugs to manage acute dystonia or parkinsonism overall during the study (OR = 5.17, 95%CI = 1.49-17.88, P = 0.013). There was no significant between-group difference in the changing of rating scales of EPS and psychotic symptoms. The results of our study favour olanzapine as a better choice in schizophrenic patients with intolerant EPS. Double-blinded, fixed dose and different ethnical study for EPS-intolerant schizophrenic patients is needed to confirm the results of our study.

Hippocampal degeneration is associated with temporal and limbic gray matter/white matter tissue contrast in Alzheimer's disease

Recent studies have demonstrated alterations in cortical gray to white matter tissue contrast with nondemented aging and in individuals with Alzheimer's disease (AD). However, little information exists about the clinical relevance of such changes. It is possible that changes in MRI tissue contrast occur via independent mechanisms from those traditionally used in the assessment of AD associated degeneration such as hippocampal degeneration measured by more traditional volumetric magnetic resonance imaging (MRI). We created cortical surface models of 95 cognitively healthy individuals and 98 individuals with AD to characterize changes in regional gray and white matter T1-weighted signal intensities in dementia and to evaluate how such measures related to classically described hippocampal and cortical atrophy. We found a reduction in gray matter to white matter tissue contrast throughout portions of medial and lateral temporal cortical regions as well as in anatomically associated regions including the posterior cingulate, precuneus, and medial frontal cortex. Decreases in tissue contrast were associated with hippocampal volume, however, the regional patterns of these associations differed for demented and nondemented individuals. In nondemented controls, lower hippocampal volume was associated with decreased gray/white matter tissue contrast globally across the cortical mantle. In contrast, in individuals with AD, selective associations were found between hippocampal volume and tissue contrast in temporal and limbic tissue. These results demonstrate that there are strong regional changes in neural tissue properties in AD which follow a spatial pattern including regions known to be affected from pathology studies. Such changes are associated with traditional imaging metrics of degeneration and may provide a unique biomarker of the tissue loss that occurs as a result of AD.

Screening and identification of male-specific DNA fragments in common carps Cyprinus carpio using suppression subtractive hybridization

In this study, a sex subtractive genomic DNA library was constructed using suppression subtractive hybridization (SSH) between male and female Cyprinus carpio. Twenty-two clones with distinguishable hybridization signals were selected and sequenced. The specific primers were designed based on the sequence data. Those primers were then used to amplify the sex-specific fragments from the genomic DNA of male and female carp. The amplified fragments from two clones showed specificity to males but not to females, which were named as Ccmf2 [387 base pairs (bp)] and Ccmf3 (183 bp), respectively. The sex-specific pattern was analysed in a total of 40 individuals from three other different C. carpio. stocks and grass carp Ctenopharyngodon idella using Ccmf2 and Ccmf3 as dot-blotting probes. The results revealed that the molecular diversity exists on the Y chromosome of C. carpio. No hybridization signals, however, were detected from individuals of C. idella, suggesting that the two sequences are specific to C. carpio. No significant homologous sequences of Ccmf2 and Ccmf3 were found in GenBank. Therefore, it was interpreted that the results as that Ccmf2 and Ccmf3 are two novel male-specific sequences; and both fragments could be used as markers to rapidly and accurately identify the genetic sex of part of C. carpio. This may provide a very efficient selective tool for practically breeding monosex female populations in aquacultural production.

The influence of lagoon on neighboring rivers by water and sediment quality

Canonical discriminant analysis (CDA) was applied in order to distinguish the water-quality and the sediment-quality parameters from neighboring rivers, and to recognize similarities of water and sediment properties between a lagoon and neighboring rivers. Two set of constructed discriminant functions showed a marked contribution to most of the discriminant variables. In water, the significant parameters - the total nitrogen, algae, dissolved oxygen and total phosphate - were combined as the nutrient effect factor. The recognition capacities of the two discriminant functions were 95.6 and 4.4%, respectively; the Kaoping River showed the most similarities with the water quality in Dapeng Bay; in sediment, the significant parameters porosity, Cd, Cr, Al, and Pb were combined as the heavy metal effect factor. The recognition capacities were 82.6 and 17.4%, respectively, but the sediment properties in these three rivers had no significant similarity with the Dapeng Bay.

Ventricular dilation and elevated aqueductal pulsations in a new experimental model of communicating hydrocephalus

In communicating hydrocephalus (CH), explanations for the symptoms and clear-cut effective treatments remain elusive. Pulsatile flow through the cerebral aqueduct is often significantly elevated, but a clear link between abnormal pulsations and ventriculomegaly has yet to be identified. We sought to demonstrate measurement of pulsatile aqueductal flow of CSF in the rat, and to characterize the temporal changes in CSF pulsations in a new model of CH. Hydrocephalus was induced by injection of kaolin into the basal cisterns of adult rats (n = 18). Ventricular volume and aqueductal pulsations were measured on a 9.4 T MRI over a one month period. Half of the animals developed ventricular dilation, with increased ventricular volume and pulsations as early as one day post-induction, and marked chronic elevations compared to intact controls (volume: 130.15 +/- 83.21 microl vs. 15.52 +/- 2.00 microl; pulsations: 114.51 nl +/- 106.29 vs. 0.72 +/- 0.13 nl). Similar to the clinical presentation, the relationship between ventricular size and pulsations was quite variable. However, the pulsation time-course revealed two distinct sub-types of hydrocephalic animals: those with markedly elevated pulsations which persisted over time, and those with mildly elevated pulsations which returned to near normal levels after one week. These groups were associated with severe and mild ventriculomegaly respectively. Thus, aqueductal flow can be measured in the rat using high-field MRI and basal cistern-induced CH is associated with an immediate change in CSF pulsatility. At the same time, our results highlight the complex nature of aqueductal pulsation and its relationship to ventricular dilation.

Preparation and photocatalytic property of TiO2-Fe3O4 core-shell nanoparticles

Titanium dioxide is an attractive photocatalytic material with a wide band gap which can be applied in chemical processes to degrade organic compounds. When TiO2 nanoparticles are dispersed in water solution in suspended state they possess high photocatalytic activity, resulting in effectively degrading the hazardous compounds in wastewater. But when the TiO2 nanoparticles are used in suspension state, it is very difficult to get them back and make them reuse, which would limit their application due to the cost. Here, we report the preparation of reusable TiO2 composite nanoparticles with a core-shell structure, which consist of a nanosized Fe3O4 core and the encapsulated TiO2 shell. The experimental result shows that these nanoparticles can be used in suspended state and exhibit high photocatalytic activity. In addition, the photocatalytic nanoparticles with core-shell structure can be easily withdrawn with a magnetic field.

Potassium permanganate as an alternative preoxidant for enhancing algal coagulation--pilot and bench scale studies

Pilot- and laboratory-scale studies were conducted to evaluate the effects of permanganate preoxidation on the removal of algae removal by coagulation. Experimental results indicate that permanganate was capable of enhancing algal coagulation. An optimum permanganate dosage for algal coagulation was identified for pilot and laboratory tests. Permanganate caused cells to liberate extracellular organic matter at the cell surfaces, thereby improving cell aggregation and increasing algae removal. Calcium enhanced the permanganate preoxidation during algal coagulation.

Reinvestigating hyperpolarized (129)Xe longitudinal relaxation time in the rat brain with noise considerations

The longitudinal relaxation time of hyperpolarized (HP) (129)Xe in the brain is a critical parameter for developing HP (129)Xe brain imaging and spectroscopy and optimizing the pulse sequences, especially in the case of cerebral blood flow measurements. Various studies have produced widely varying estimates of HP (129)Xe T(1) in the rat brain. To make improved measurements of HP (129)Xe T(1) in the rat brain and investigate how low signal-to-noise ratio (SNR) contributes to these discrepancies, we developed a multi-pulse protocol during the washout of (129)Xe from the brain. Afterwards, we applied an SNR threshold theory to both the multi-pulse protocol and an existing two-pulse protocol. The two protocols yielded mean +/- SD HP (129)Xe T(1) values in the rat brain of 15.3 +/- 1.2 and 16.2 +/- 0.9 s, suggesting that the low SNR might be a key reason for the wide range of T(1) values published in the literature, a problem that might be easily alleviated by taking SNR levels into account.

Non-linear optical properties of zinc oxide nanowires

High quality zinc oxide (ZnO) nanowires were grown on n-type Si (100) using vapor-liquid-solid process. We obtained the photoluminescence spectra of ZnO nanowires based on nonlinear optical process using an ultrashort wavelength femtosecond laser as a pumping source. The spectra shows the second harmonic generation phenomenon, as well as the exciton-exciton collision peak at 388 nm and the green emission peak at 515 nm caused by oxygen vacancy. A laser emission peak near 392 nm was observed when pump intensity surpassed 52 mJ/cm2 and a sharp peak about 0.5 nm wide emerged when the energy intensity reached 700 mJ/cm2. We attribute this excitation process to a two-photon absorption process enhanced by Rabi oscillation.

Systemic lupus erythematosus: a genetic epidemiology study of 695 patients from China

Our purpose was to explore potential genetic models for systemic lupus erythematosus (SLE) and analyze genetic epidemiologic characteristics of SLE in a Chinese population. Data for 695 patients with SLE were obtained by using a uniform questionnaire. Patients, clinical characteristics and their family history were analyzed using software. A complex segregation analysis was conducted to propose potential genetic models for SLE. The mean +/- SD age of onset were 30.2 +/- 10.5 years and mean time to progression to SLE was 32.5 +/- 44.4 months. The most frequent initial manifestations were malar rash (61.3%). During the evolution of the disease, the main clinical features were arthritis in 73.6% of our patients, followed by malar rash (68.1%), and renal involvement (56.7%). As the first symptom, the late-onset group (onset of disease beyond the age of 50 years) less often showed malar rash (45% vs. 63.4% in the early-onset group; p = 0.001). There were no significant differences in the other cumulative clinical symptoms between late-onset and early-onset group, except for a lower prevalence of malar rash, photosensitivity and alopecia and a higher prevalence of mucosal ulcers in the late-onset group. A positive family history of SLE was obtained in 50 patients (7.2%). There were no statistical differences in clinical characteristics between familial SLE and sporadic SLE patients. The heritability of SLE was 43.6%, the genetic model of SLE could be polygenetic model and major gene mode is the best fitted one. SLE could be a multifactorial disease with polygenetic model.

Partial volume effect in quantitative magnetic resonance perfusion imaging

In dynamic-susceptibility contrast (DSC) magnetic resonance (MR) perfusion imaging, the cerebral blood flow (CBF) is estimated from the tissue residue function obtained through deconvolution of the contrast concentration functions. However, the reliability of CBF estimates obtained by deconvolution is sensitive to various distortions. Among the most prominent experimental limitations is the image spatial resolution, leading to partial volume effect (PVE), which arises when the size of the voxel exceeds the volume containing the arterial input signal. PVE results in distortion of the arterial input function (AIF), and directly leads to miscalculation of the CBF. This work demonstrates the degree of the CBF estimation bias that could develop as a result of PVE.

Selection of differentially expressed genes in microarray data analysis

One common objective in microarray experiments is to identify a subset of genes that express differentially among different experimental conditions, for example, between drug treatment and no drug treatment. Often, the goal is to determine the underlying relationship between poor versus good gene signatures for identifying biological functions or predicting specific therapeutic outcomes. Because of the complexity in studying hundreds or thousands of genes in an experiment, selection of a subset of genes to enhance relationships among the underlying biological structures or to improve prediction accuracy of clinical outcomes has been an important issue in microarray data analysis. Selection of differentially expressed genes is a two-step process. The first step is to select an appropriate test statistic and compute the P-value. The genes are ranked according to their P-values as evidence of differential expression. The second step is to assign a significance level, that is, to determine a cutoff threshold from the P-values in accordance with the study objective. In this paper, we consider four commonly used statistics, t-, S- (SAM), U-(Mann-Whitney) and M-statistics to compute the P-values for gene ranking. We consider the family-wise error and false discovery rate false-positive error-controlled procedures to select a limited number of genes, and a receiver-operating characteristic (ROC) approach to select a larger number of genes for assigning the significance level. The ROC approach is particularly useful in genomic/genetic profiling studies. The well-known colon cancer data containing 22 normal and 40 tumor tissues are used to illustrate different gene ranking and significance level assignment methods for applications to genomic/genetic profiling studies. The P-values computed from the t-, U- and M-statistics are very similar. We discuss the common practice that uses the P-value, false-positive error probability, as the primary criterion, and then uses the fold-change as a surrogate measure of biological significance for gene selection. The P-value and the fold-change can be pictorially shown simultaneously in a volcano plot. We also address several issues on gene selection.

Hierarchical models for probabilistic dose–response assessment

Probabilistic risk assessment is gaining acceptance as the most appropriate way to characterize and communicate uncertainties in estimates of human health risk and/or reference levels of exposure such as benchmark doses. Although probabilistic techniques are well established in the exposure-assessment component of the National Research Council's risk-assessment paradigm, they are less well developed in the dose-response-assessment component. This paper proposes the use of hierarchical statistical models as tools for implementing probabilistic dose-response assessments, in that such models provide a natural connection between the pharmacokinetic (PK) and pharmacodynamic (PD) components of dose-response models. The results show that incorporating internal dose information into dose-response assessments via the coupling of PK and PD models in a hierarchical structure can reduce the uncertainty in the dose-response assessment of risk. However, information on the mean of the internal dose distribution is sufficient; having information on the variance of internal dose does not affect the uncertainty in the resulting estimates of excess risks or benchmark doses. In addition, the complexity of a PK model of internal dose does not affect how the variability in risk is measured via the ultimate endpoint.

Decision threshold adjustment in class prediction

Standard classification algorithms are generally designed to maximize the number of correct predictions (concordance). The criterion of maximizing the concordance may not be appropriate in certain applications. In practice, some applications may emphasize high sensitivity (e.g., clinical diagnostic tests) and others may emphasize high specificity (e.g., epidemiology screening studies). This paper considers effects of the decision threshold on sensitivity, specificity, and concordance for four classification methods: logistic regression, classification tree, Fisher's linear discriminant analysis, and a weighted k-nearest neighbor. We investigated the use of decision threshold adjustment to improve performance of either sensitivity or specificity of a classifier under specific conditions. We conducted a Monte Carlo simulation showing that as the decision threshold increases, the sensitivity decreases and the specificity increases; but, the concordance values in an interval around the maximum concordance are similar. For specified sensitivity and specificity levels, an optimal decision threshold might be determined in an interval around the maximum concordance that meets the specified requirement. Three example data sets were analyzed for illustrations.

Differential leg function in a sprawled-posture quadrupedal trotter

Legs of sprawled-posture, quadrupedal trotting geckos (Hemidactylus garnotii) each functioned differently during constant average-speed locomotion. The center of mass decelerated in the first half of a step and accelerated in the second half, as if geckos were bouncing in fore–aft and side-to-side directions. Forelegs decelerated the center of mass only in the fore–aft direction. Hindlegs provided all the acceleration in the latter half of the step. Lateral ground reaction forces were always directed toward the midline and exceeded the magnitude of fore–aft forces. The differential leg function of sprawled-posture geckos resembled sprawled-posture hexapods more than upright-posture quadrupeds. The pattern of leg ground reaction forces observed may provide passive, dynamic stability while minimizing joint moments, yet allow high maneuverability. Integrating limb dynamics with whole body dynamics is required to resolve the trade-offs,if any, that result from stable sprawled-posture running with differential leg function.

Water quality assessment and apportionment source of pollution from neighbouring rivers in the Tapeng Lagoon (Taiwan) using multivariate analysis: a case study

Factor analysis was conducted to explain the characteristics and variation in the quality of water during the disassembly of oyster frames and fishery boxes. The result shows that the most important latent factors in the Tapeng Lagoon are the ocean factor, the primary productivity factor, and the fishery pollution factor. Canonical discriminant analysis is applied to identify the source of pollution in neighbouring rivers outside the Tapeng Lagoon. The two constructed discriminant functions (CDFs) showed a marked contribution to all the discriminant variables, and that total nitrogen, algae, dissolved oxygen, and total phosphate combined in the nutrient effect factor. The recognition capacities in these two CDFs were 95.6% and 4.4%, respectively. The water quality in the Kaoping river most strongly affected the water quality in the Tapeng Lagoon. Disassembling the oyster frames and fishery boxes improved the water quality markedly. However, environmental topographic conditions indicate that strengthening stream pollution prevention and constructing another entrance to the ocean are the best approaches for improving the quality of water in the Tapeng Lagoon by reducing eutrophication. These approaches and results yield useful information concerning habitat recovery and water resource management.

Classification ensembles for unbalanced class sizes in predictive toxicology

This paper investigates the effects of the ratio of positive-to-negative samples on the sensitivity, specificity, and concordance. When the class sizes in the training samples are not equal, the classification rule derived will favor the majority class and result in a low sensitivity on the minority class prediction. We propose an ensemble classification approach to adjust for differential class sizes in a binary classifier system. An ensemble classifier consists of a set of base classifiers; its prediction rule is based on a summary measure of individual classifications by the base classifiers. Two re-sampling methods, augmentation and abatement, are proposed to generate different bootstrap samples of equal class size to build the base classifiers. The augmentation method balances the two class sizes by bootstrapping additional samples from the minority class, whereas the abatement method balances the two class sizes by sampling only a subset of samples from the majority class. The proposed procedure is applied to a data set to predict estrogen receptor binding activity and to a data set to predict animal liver carcinogenicity using SAR (structure-activity relationship) models as base classifiers. The abatement method appears to perform well in balancing sensitivity and specificity.

Refined localization of a punctate palmoplantar keratoderma gene to a 5.06-cM region at 15q22.2-15q22.31

BACKGROUND

Punctate palmoplantar keratoderma (PPK) is a rare autosomal dominant cutaneous disorder characterized by numerous hyperkeratotic papules distributed on the palms and soles. Two loci for punctate PPK were recently found to be located on 8q24.13-8q24.21 and 15q22-15q24. However, no genes for this disease have been identified to date. Objectives To refine the previously mapped regions and to identify the disease gene locus in a four-generation Chinese family with punctate PPK.

METHODS

Genetic linkage analysis was carried out in this family using microsatellite markers on chromosomes 8q and 15q. Two-point linkage analysis was performed using Linkage programs version 5.10 and the haplotype was constructed using Cyrillic version 2.02 software.

RESULTS

We failed to confirm our previous locus at 8q24.13-8q24.21, but significant evidence for linkage was observed in the region of 15q with a maximum two-point LOD score of 5.38 at D15S153 (theta = 0.00). Haplotype analysis localized the punctate PPK locus within the region defined by D15S651 and D15S988. This region overlaps by 5.06 cM with the previously reported punctate PPK region.

CONCLUSIONS

This study refines a disease gene causing punctate PPK to a 5.06-cM interval at 15q22.2-15q22.31.

Development of interesting step-climbing styles

OBJECTIVES

This study was to investigate the influence of stepping styles (forward, side, and cross steppings) and inclinations (25 and 45 degrees) on cardiorespiratory responses (C-R responses).

METHODS

Twenty volunteers were recruited and randomly arranged into two ten-people groups, exercising on step-climbing machines respectively of 25 and 45 degrees of inclination. C-R responses were recorded during each test which lasted for six minutes at 50 steps per minute on a step-climbing machine.

RESULTS

The group on 25-degree inclination had significantly lower C-R responses than the group on 45-degree inclination. Although only small differences, probably statistically insignificant, were found among the three step-climbing styles, these differences showed interesting trends independent of inclination.

CONCLUSIONS

Climbing stairs with the three interesting step-climbing styles in this study could be considered as an exercise of moderate intensity (60-80% HRmax ). Climbing on 25-degree inclination at 50 steps per minute is recommended for less fit individuals because of lower cardiovascular stress as compared with on 45-degree inclination.