[Two outbreaks of eosinophilic meningitis in Yunann (China) clinical, epidemiological and therapeutical issues]

Eosinophilic meningitis is an uncommon clinical entity, which is mostly caused by Angiostrongylus cantonensis, a nematode which parasitizes rat's lungs. Humans represent a dead-end in the parasite's lifecycle and become infected by ingesting snails, slugs or transport hosts. Due to uncontrolled proliferation and circulation of snails and rats, human angiostrongyliasis has emerged in new foci in continental China. The treatment, which relies upon a combination of albendazole and corticosteroids, is still a matter of debate. In order to assess the epidemiological features of two outbreaks which occurred in Kunming, capital of the Yunnan province, 2003 and 2005, along with the clinical and treatment issues, a retro-prospective study was carried out among thirty-four clinical cases of eosinophilic meningitis. Furthermore, a parasitological survey was carried out on randomized samples of snails sold in the markets of the city On admission, all cases were found to have acute headaches and an eosinophilic pleocytosis rate > 5% in the cerebro spinal fluid (CSF). All patients reported the consumption of raw snails Pomacea canaliculata, 14 days on average before the onset of headaches (range 1-30 days). Hyperesthesia due to radiculitis was observed in 68% of the cases and the meningitis syndrome was present in 41%. The average value of blood eosinophil count in CSF and in peripheral blood was 38% and 900/ml, respectively. Two treatment schedules were used (without randomization): one with progressive doses over 4 weeks; the other with immediate high doses for 10 days with 3 sessions separated by 14-day intervals. The results were compared by the Kaplan Meier log rank test. All the cases had a favorable evolution. The analysis suggested better effectiveness and tolerance of the albendazole - dexamethasone combination used at the highest dosage, namely 20mglkg daily and 10mg daily respectively. Eosinophilic meningitis appeared to be recently emerging or re-emerging in Kunming. Deep-rooted culinary habits of eating raw food, and large amount of snails sold on local markets (about one ton per day) provide ideal conditions for the outbreak, or occurrence of this disease. According to the resdjlts of this study Chinese local authorities should be urged to improve information to the population about the risks of eating raw snails, in order to strengthen the control of both rat and snail populations and reinforce the supervision of local food markets.

ER-α36, a variant of ER-α, is the estrogen receptor that mediates mitogenic estrogen signaling in breast cancer cells

Abstract #18

The role of endogenous estrogens in breast cancer etiology has been well established. Dysregulated estrogen signaling increases the rate of cell proliferation and thus the risk of breast cancer. However, despite widespread agreement that estrogens are involved in breast cancer etiology, the molecular mechanisms of estrogen action, especially those by which estrogen signaling stimulates mammary tumorigenesis and breast cancer progression have not been well established.
 Recently, we have identified and cloned a 36-kDa novel isoform of estrogen receptor α (ER-α36) that is generated from a promoter located in the first intron of the original 66-kDa ER-α (ER-α66) gene. The ER-α36 differs from the ER-α66 by lacking both transcriptional activation domains (AF-1 and AF-2) but retains the DNA-binding, dimerization and most of the ligand-binding domains. ER-α36 is mainly expressed on the plasma membrane and mediates membrane-initiated estrogen signaling that activates the MAPK/ERK pathway and stimulates cell proliferation. ER-α36 inhibits the genomic estrogen signaling mediated by the AF1 and AF2 domains of ER-α66 and ligand-dependent and -independent transactivation activities of ER-β. We designed and constructed shRNA expression vectors to express shRNAs specific for ER-α36 or ER-α66. We found that ER-positive breast cancer cells MCF7 and T47D expressing ER-α36 shRNA that successfully knockdown about 90% ER-α36 expression failed to respond to estrogen stimulation. However, estrogen strongly stimulated cell growth in MCF7 and T47D cells with ER-α66 knockdown. We found that some estrogen responsive genes such as c-Myc, CyclinD1 and progesterone receptor (PR) were induced through the extra-nuclear estrogen signaling pathway while pS2 was induced by the nuclear pathway. Our results for the first time demonstrated that ER-α36, not the original ER-α36 is the estrogen receptor that actually mediates estrogen-stimulated cell proliferation in breast cancer cells.
 Among 800 cases of human breast cancer specimens examined, ER-α36 is expressed in most of the breast cancer specimens, and even in 40% of ER-negative breast cancer cases that lack expression of ER-α66. In addition, ER-α36 expressing patients responded poorly to anti-estrogen Tamoxifen treatment. In vitro study revealed that breast cancer cells that highly express ER-α36 exhibited estrogen hypersensitivity and Tamoxifen resistance, consistent with the clinical evidence that breast cancers expressing ER-α36 exhibit higher degree of malignancy and poorer survival rate.
 Taken together, our results demonstrated that ER-α36 is a novel player in mitogenic estrogen signaling that plays an important role in estrogen stimulated mammary carcinogenesis.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 18.

The cartilage chondrolytic mechanism of fibronectin fragments involves MAP kinases: comparison of three fragments and native fibronectin

OBJECTIVE

To define the role of mitogen activated protein (MAP) kinases in fibronectin fragment (Fn-f) mediated matrix metalloproteinase (MMP) upregulation and damage to bovine cartilage and to compare activities of three Fn-fs with native fibronectin (Fn), which is inactive in terms of cartilage damage.

METHODS

Bovine chondrocytes were cultured with three Fn-fs, an amino-terminal 29-kDa, a gelatin-binding 50-kDa and a central 140-kDa Fn-f or native Fn at concentrations from 0.01 to 1 microM, concentrations lower than those found in osteoarthritis synovial fluids. Lysates were probed for activation of MAP kinases, extracellular signal-regulated kinase 1/2 (ERK1/2), p38 and stress activated protein kinase/c-jun N-terminal kinase (SAPK/JNK). Confocal fluorescent microscopy was used to visualize movement of activated kinases. Kinase inhibitors were tested for their abilities to block Fn-f mediated protein upregulation of MMP-3 and MMP-13 and Fn-f induced depletion of cartilage proteoglycan (PG) from cultured explants.

RESULTS

The 29-kDa, the most potent Fn-f in terms of cartilage damage, enhanced phosphorylation of ERK1/2, p38 and JNK1/2 within a 1-h incubation while the 50 and 140-kDa Fn-fs required up to 4 h for maximal activity and native Fn was only minimally active toward p38 and JNK, but did strongly activate ERK1/2. The activated kinases displayed a distribution toward the nuclear membrane and within the nucleus. MAP kinase inhibitors markedly decreased Fn-f mediated upregulation of MMP-3 or MMP-13 and Fn-f mediated cartilage PG depletion.

CONCLUSIONS

These results suggest that Fn-fs upregulate MMP-3 and MMP-13 in bovine chondrocytes through MAP kinases and that kinase inhibitors afford protection against this degenerative pathway.

Anomalous transport properties and phase diagram of the FeAs-based SmFeAsO1-xFx superconductors

We report the detailed phase diagram and anomalous transport properties of Fe-based high-T_{c} superconductors SmFeAsO1-xFx. It is found that superconductivity emerges at x approximately 0.07, and optimal doping takes place in the x approximately 0.20 sample with the highest T_{c} approximately 54 K. T_{c} increases monotonically with doping; the anomaly in resistivity from structural phase or spin-density-wave order is rapidly suppressed, suggesting a quantum critical point around x approximately 0.14. As manifestations, a linear temperature dependence of the resistivity shows up at high temperatures in the x<0.14 regime but at low temperatures just above T_{c} in the x>0.14 regime; a drop in carrier density evidenced by a pronounced rise in the Hall coefficient is observed below the temperature of the anomaly peak in resistivity. A scaling behavior is observed between the Hall angle and temperature: cottheta_{H} proportional, variantT;{1.5} for all samples with different x in SmFeAsO1-xFx system.

Evolution of photoluminescence mechanisms of Si(+)-implanted SiO2 films with thermal annealing

The information of band structure of silicon nanocrystal (nc-Si) embedded in SiO2 thin films synthesized by Si ion implantation and subsequent thermal annealing at various temperatures has been obtained from spectroscopy ellipsometric (SE) analysis. The indirect band structure and the energy gap of the nc-Si are not affected by the annealing. In contrast, the photoluminescence (PL) spectra show a continuous evolution with the annealing. Six PL bands located at 415, 460, 520, 630, 760, and 845 nm, respectively, have been observed depending on the annealing temperature. The annealing at 1100 degrees C yields the strongest PL band at 760 nm (approximately 1.63 eV) with the intensity much higher than that of all the other PL bands. Based on the knowledge of the band structure, the 760 nm-PL band could be attributed to the indirect band-to-band transition of the nc-Si assisted by the Si-O vibration of the nc-Si/SiO2 interface with the stretching frequency of approximately 1083 cm(-1) (approximately 0.13 eV). On the other hand, the first four PL bands mentioned above could originate from different extended defects in the oxide matrix, while the 845-nm PL band could be related to the interface luminescent centers.

Spatio-temporal source localization and Granger causality in ictal source analysis

We have proposed a new ictal source analysis approach by combining a spatio-temporal source localization approach, and causal interaction estimation technique. The FINE approach is used to identify neural electrical sources from spatio-temporal scalp-EEGs. The Granger causality estimation uses source waveforms estimated by FINE to characterize the causal interaction between the neural electrical sources in order to distinguish primary sources, which initiate ictal events, from secondary sources, which are caused by propagation. In the present study, we applied the proposed analysis approach to an epilepsy patient with symptomatic MRI lesions. It is found that the primary ictal source is within the visible lesion, which gave the consistent presurgical evaluation as MRI for this patient.

Development of a real-time PCR assay for the detection of Cladosporium fulvum in tomato leaves

AIMS

The aim of this study was to develop a sensitive real-time polymerase chain reaction (PCR) assay for the rapid detection of Cladosporium fulvum in tomato leaves.

METHODS AND RESULTS

Three PCR primer pairs were designed based on the nucleotide sequences of: (i) the internal transcribed spacer regions of ribosomal RNA; (ii) a microsatellite region amplified by the microsatellite primer M13; and (iii) the beta-tubulin gene of C. fulvum. Each primer pair amplified the expected target DNA fragment from geographically diverse isolates of C. fulvum. No PCR products were amplified with these primer pairs from DNA of other fungal species. Among the three pairs of primers, the primer pair CfF1/CfR1 developed based on the microsatellite region was the most sensitive. Using this sensitive primer pair, a real-time PCR assay was developed to detect early infection of C. fulvum in tomato leaves.

SIGNIFICANCE AND IMPACT OF THE STUDY

DNA regions amplified by the microsatellite primer M13 have a high potential for developing highly sensitive species-specific PCR primers for the detection of phytopathogenic fungi. The real-time PCR assay developed in this study is useful in monitoring early infection of C. fulvum, and can help growers make timely decisions on fungicide application.

A novel HLA-C allele, Cw*0119, isolated from the Han Chinese

A novel HLA-C allele, Cw*0119, which was identified from an individual of the Han Chinese, differs from Cw*010201 at codon 76 (AGC-->TGC) and codon 178 (CTG-->CCG).

Imaging functional brain connectivity patterns from high-resolution EEG and fMRI via graph theory

We describe a set of computational tools able to estimate cortical activity and connectivity from high-resolution EEG and fMRI recordings in humans. These methods comprise the estimation of cortical activity using realistic geometry head volume conductor models and distributed cortical source models, followed by the evaluation of cortical connectivity between regions of interest coincident with the Brodmann areas via the use of Partial Directed Coherence. Connectivity patterns estimated on the cortical surface in different frequency bands are then imaged and interpreted with measures based on graph theory. These computational tools were applied on a set of EEG and fMRI data from a Stroop task to demonstrate the potential of the proposed approach. The present findings suggest that the methodology is able to identify differences in functional connectivity patterns elicited by different experimental tasks or conditions.

Defects in ZnO nanorods prepared by a hydrothermal method

ZnO nanorod arrays were fabricated using a hydrothermal method. The nanorods were studied by scanning electron microscopy, photoluminescence (PL), time-resolved PL, X-ray photoelectron spectroscopy, and positron annihilation spectroscopy before and after annealing in different environments and at different temperatures. Annealing atmosphere and temperature had significant effects on the PL spectrum, while in all cases the positron diffusion length and PL decay times were increased. We found that, while the defect emission can be significantly reduced by annealing at 200 degrees C, the rods still have large defect concentrations as confirmed by their low positron diffusion length and short PL decay time constants.

Characterisation of insulin-resistant phenotype of cultured rat primary adipose cells

AIMS/HYPOTHESIS

We characterised insulin resistance, metabolic defects and endocrine dysfunction in cultured adipose cells and examined the autocrine or paracrine roles of cytokines/adipokines in the progression of insulin resistance.

MATERIALS AND METHODS

Rat primary adipose cells were prepared and cultured for 24 and 48 h. Insulin resistance and gene expression were examined by glucose uptake assay, cDNA microarray and real-time RT-PCR.

RESULTS

After 24 h in culture, the fold increase of insulin-stimulated glucose uptake in adipose cells was markedly reduced; after 48 h the response of the cells to insulin decreased. cDNA microarray analysis showed that the expression of 514 genes was altered in adipose cells after 24 h in culture. The dysregulated genes included those involved in the citric acid cycle and in fatty acid and pyruvate metabolism. Specifically, the following genes were all downregulated: genes encoding lipolytic and lipogenic enzymes; uncoupling protein 1 and 2 genes; peroxisome proliferator-activated receptor gamma, coactivator 1 alpha gene. This indicates that lipolytic and lipogenic activity, as well as mitochondria capacity decline in adipose cells cultured for 24 h. The mRNAs encoding 40 adipokines were also dysregulated in cultured cells. Strikingly, the dysregulated adipokines in cultured cells and in freshly isolated adipose cells from insulin-resistant Zucker fa/fa rats displayed a similar pattern with regard to protein functions. Also striking was the fact that progression of insulin resistance was promoted by the adipokines secreted from insulin-resistant adipose tissue or cells.

CONCLUSIONS/INTERPRETATION

Our data demonstrate that the impairment of metabolism and endocrine dysfunction in cultured adipose cells mimics the insulin resistance occurring in vivo. Cytokines and adipokines appear to play a critical role in the progression of insulin resistance in adipose cells.

Improved estimation of human cortical activity and connectivity with the multimodal integration of neuroelectric and hemodynamic data

In the last decade, the possibility to noninvasively estimate cortical activity and connectivity has been highlighted by the application of the techniques known as high resolution EEG. These techniques include a subject's multi-compartment head model (scalp, skull, dura mater, cortex) constructed from individual magnetic resonance images, multi-dipole source model, and regularized linear inverse source estimates of cortical current density. More recently, it has proved as the use of information from the hemodynamic responses of the cortical areas as revealed by block-designed (strength of activated voxels) fMRI improves dramatically the estimates of cortical activity and connectivity. Here, we present some applications of such estimation in two set of high resolution EEG and fMRI data, related to the motor (finger tapping) and cognitive (Stroop) tasks. We observed that the proposed technology was able to unveil the direction of the information flow between the cortical regions of interest.

Time-varying cortical connectivity by high resolution EEG and directed transfer function: simulations and application to finger tapping data

The problem of the definition and evaluation of brain connectivity has become a central one in neuroscience during the latest years, as a way to understand the organization and interaction of cortical areas during the execution of cognitive or motor tasks. The method of the directed transfer function (DTF) is a frequency-domain approach to this problem, based on a multivariate autoregressive modeling of time series and on the concept of Granger causality. So far, all the connectivity estimations performed on cerebral electromagnetic signals were computed between signals gathered from the electric or magnetic sensors. However, the spreading of the potential from the cortex to the sensors makes it difficult to infer the relation between the spatial patterns on the sensor space and those on the cortical sites. In this paper we propose the use of the DTF method on cortical signals estimated from high resolution EEG recordings, which exhibit a higher spatial resolution than conventional cerebral electromagnetic measures. As main contributions of this work, we present the results of a wide simulation study, aiming to evaluate performances of DTF application on this kind of data, and a statistical analysis (via the ANOVA, analysis of variance) of the results obtained for different levels of signal to noise ratio and temporal length, as they have been systematically imposed on simulated signals. Finally, we provide an application to the estimation of cortical connectivity from high resolution EEG recordings related to finger tapping movements.

Motor imagery classification by means of source analysis methods

We report our investigation of classification of imagined left and right hand movements by applying source analysis methods. Independent component analysis (ICA) is used as a spatio-temporal filter, then equivalent dipole analysis and cortical current density imaging methods are applied to reconstruct equivalent sources, to aid classification of motor imagery tasks in a human subject. The classification was considered correct if the equivalent source was found over the motor cortex in the corresponding hemisphere. A classification rate of about 80% was achieved in the human subject studied using both the equivalent dipole analysis and the cortical current density imaging analysis.