MRI findings of eosinophilic myelomeningoencephalitis due to Angiostrongylus cantonensis

AIM

To study the imaging characteristics of eosinophilic myelomeningoencephalitis due to Angiostrongylus cantonensis using magnetic resonance imaging (MRI).

MATERIALS AND METHODS

Seventeen MRI examinations of the brain and spinal cord in five patients with angiostrongyliasis cantonensis of the central nervous system were performed. The final diagnosis was based on typical clinical symptoms, results of blood and cerebrospinal fluid (CSF) tests, and the presence of nematode larvae in the CSF. The sequential MRI follow-up examinations were carried out at a different stage for every patient from 1 to 28 weeks after the onset of symptoms. The features of the lesions in the brain, spinal cord, meninges and nerve roots on MRI were studied, moreover, the development of the lesions was analysed on follow-up MRI.

RESULTS

Abnormalities were demonstrated on MRI in all five cases. They included three cases of meningoencephalitis, one case of encephalitis and one myelomeningitis. The locations and appearances of the lesions were as follows: (1) brain involvement in four cases (including cerebrum in four, cerebellum in two and brain stem in three), and spinal cord involvement in one case. These lesions were diffuse or scattered and appeared as similar or slightly reduced signal intensity on T1-weighted images (T1WI), high signal intensity on T2-weighted images (T2WI) and turbo fluid attenuated inversion recovery pulse sequence (FLAIR) images. After administration of gadolinium chelate (Gd-DTPA), multiple round or oval enhancing nodules, with diameters ranging from 3 to 10 mm, were seen on T1WI, a few lesions appeared as stick-shaped enhancement whose longest measurement was 14 mm. Diffuse or local oedema around the lesion could be seen. (2) Meningeal involvement in four cases, a case of ependymal involvement and a case of nerve root involvement were among them. These lesions appeared as linear or nodular enhancement of the leptomeninges and ependyma, as well as nerve root enhancement. (3) There was a mild ventricular enlargement in two cases. On follow-up MRI lesions were most severe from the 5th week to the 8th week and it took at least 4-8 weeks (1-2 months) for a lesion to resolve completely, the resolution of larger lesion needed more than 22 weeks.

CONCLUSION

Multiple enhancing nodules in the brain and linear enhancement in the leptomeninges were the main features; stick-shaped enhancement was the characteristic sign of the disease on Gd-DTPA enhanced-T1 weighted images.

Soft drink and milk consumption, physical activity, bone mass, and upper limb fractures in children: a population-based case-control study

Carbonated beverages have been reported to increase fracture risk in children but the mechanism is unclear. The aim of this population-based case-control study was to investigate the association between soft drink and milk consumption, physical activity, bone mass, and upper limb fractures in children aged 9-16 years. A total of 206 fracture cases and 206 randomly selected individually matched controls were studied. There were 47 hand fractures; 128 wrist and forearm fractures, and 31 upper arm fractures. An interviewer-administered questionnaire was utilized to retrospectively assess last-year physical activity (including television, computer, and video watching) and to recall the average weekly consumption of milk, colas, and total carbonated drinks. Bone mass at the spine, hip, and total body was assessed by dual-energy X-ray absorptiometry (DXA) and metacarpal morphometry. For total fractures, none of the above drink types was significantly different between cases and controls. For wrist and forearm fractures, there was a positive association between cola drink consumption and fracture risk (OR 1.39/unit, 95% CI: 1.01, 1.91). Cola consumption was significantly correlated with television, computer, and video watching (r = 0.20, P = 0.001) but not bone mineral density or milk drinks. After adjustment for television, computer, and video watching and bone mineral density, the association between cola drinks and fracture risk became nonsignificant (OR 1.31/unit, 95% CI: 0.94, 1.83). No association with other fracture sites was observed. In conclusion, cola, but not total carbonated beverage consumption, is associated with increased wrist and forearm fracture risk in children. However, this association is not independent of other factors and appears to be mediated by television watching and bone mineral density but not by decreased milk intake.

A phase II study of Rituximab in rheumatoid arthritis patients with recurrent disease following haematopoietic stem cell transplantation

Haematopoietic stem cell transplantation (HSCT) has been used recently as an effective therapy in patients with resistant rheumatoid arthritis (RA). Although disease control occurs in the majority of cases, recurrence is common, often coinciding with B-cell reconstitution. We hypothesized that Rituximab, a monoclonal anti-CD20 antibody, would have activity in this group of patients. We treated 10 RA patients (8F:2M, median age 46.5 years), who had recurrent disease post HSCT. All patients received two doses of Rituximab 1 g, 2 weeks apart with no major adverse sequelae and were followed for 12 months. A total of eight out of 10 patients experienced major clinical responses as measured by the American College of Rheumatology (ACR) criteria, with 50-70% improvement in disease parameters. Responses were equivalent to previous responses attained with HSCT. Disease responses were maximal at 4-8 months post Rituximab and correlated with B-cell lymphopenia and a reduction of rheumatoid factor titre. Disease recurrence occurred in 6/9 responders within 12 months and four patients were subsequently retreated, with major responses again attained. This study provides further evidence that B-cell depletion leads to a significant improvement in disease activity in patients with severe RA and provides data for future trials of HSCT and Rituximab therapy.

Analysis of lectin receptors in normal nasal mucosa, nasal polyp, inverted papilloma and papillary adenocarcinoma

In order to investigate the changes in glycoprotein structure in the process of cellular differentiation of the nasal mucosa, formalin-fixed, paraffin-embedded biopsy specimens of normal nasal mucosae, nasal polyps, inverted papillomas and papillary adenocarcinomas were analysed by the Avidin Biotin-Peroxidase Complex technique for the demonstration of peanut agglutinin (PNA) receptors, concanavalin ensifomis agglutinin (ConA) receptors, ulex europeaus agglutinin (UEA-I) receptors, wheat germ agglutinin (WGA) receptors, carcino-embryonic antigen (CEA) and keratin. The quantity and distribution of PNA receptors, ConA receptors, UEA-I receptors and CEA were different, in relation to the varying pathological changes. The results suggest that the glycoprotein structure in the cells of the nasal mucosa will change following their differentiation and malignant transformation, which may be helpful in establishing the diagnosis.

The role of protein kinase C-alpha (PKC-alpha) in malignancies of the gastrointestinal tract

Drugs specifically designed to block cellular signalling proteins are currently evaluated as a new way to treat gastrointestinal tumours. One such "new targeted agent" is aprinocarsen, an antisense oligonucleotide that specifically blocks the mRNA of protein kinase C-alpha (PKC-alpha). Blocking PKC-alpha, an important cellular signalling molecule associated with tumour growth, is anticipated to result in tumour cell arrest and achieve clinical benefits. However, it is not known which patients may benefit most from a specific inhibition of PKC-alpha. Past experience with other novel targeted agents suggests that expression of the target molecule is an important factor for the success of such a specific therapy. Therefore, reviewing the specific role of PKC-alpha in various gastrointestinal tumours may contribute to focus the clinical development of selective or specific PKC-alpha inhibitors, such as aprinocarsen, on those patients with a distinctive PKC-alpha expression pattern.

Imatinib produces significantly superior molecular responses compared to interferon alfa plus cytarabine in patients with newly diagnosed chronic myeloid leukemia in chronic phase

We analyzed molecular responses in 55 newly diagnosed chronic-phase chronic myeloid leukemia (CML) patients enrolled in a phase 3 study (the IRIS trial) comparing imatinib to interferon-alfa plus cytarabine (IFN+AraC). BCR-ABL/BCR% levels were measured by real-time quantitative RT-PCR and were significantly lower for the imatinib-treated patients at all time points up to 18 months, P<0.0001. The median levels for imatinib-treated patients continued to decrease and had not reached a plateau by 24 months. A total of 24 IFN+AraC-treated patients crossed over to imatinib. Once imatinib commenced, the median BCR-ABL/BCR% levels in these patients were not significantly different to those on first-line imatinib for the equivalent number of months. The incidence of progression in imatinib-treated patients, defined by hematologic, cytogenetic or quantitative PCR criteria, was significantly higher in the patients who failed to achieve a 1 log reduction by 3 months or a 2 log reduction by 6 months, P=0.002. A total of 49 patients were screened for BCR-ABL kinase domain mutations. Mutations were detected in two imatinib-treated patients who crossed over from IFN+AraC and both lost their imatinib response. In conclusion, first-line imatinib-treated patients had profound reductions in BCR-ABL/BCR%, which significantly exceeded those of IFN+AraC-treated patients and early measurements were predictive of subsequent response.

Synthesis and evaluation of novel bifunctional chelating agents based on 1,4,7,10-tetraazacyclododecane-N,N',N",N"'-tetraacetic acid for radiolabeling proteins

Detailed synthesis of the bifunctional chelating agents 2-methyl-6-(p-isothiocyanatobenzyl)-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (1B4M-DOTA) and 2-(p-isothiocyanatobenzyl)-5, 6-cyclohexano-1, 4, 7, 10-tetraazacyclododecane-1, 4, 7, 10-tetraacetate (CHX-DOTA) are reported. These chelating agents were compared to 2-(p-isothiocyanatobenzyl)-1, 4, 7, 10-tetraazacyclododecane-1, 4, 7, 10-tetraacetic acid (C-DOTA) and 1, 4, 7, 10-Tetraaza-N-(1-carboxy-3-(4-nitrophenyl)propyl)-N', N", N"'-tris(acetic acid) cyclododecane (PA-DOTA) as their (177)Lu radiolabeled conjugates with Herceptin. In vitro stability of the immunoconjugates radiolabeled with (177)Lu was assessed by serum stability studies. The in vivo stability of the radiolabeled immunoconjugates and their targeting characteristics were determined by biodistribution studies in LS-174T xenograft tumor-bearing mice. Relative radiolabeling rates and efficiencies were determined for all four immunoconjugates. Insertion of the 1B4M moiety into the DOTA backbone increases radiometal chelation rate and provides complex stability comparable to C-DOTA and PA-DOTA while the CHX-DOTA appears to not form as stable a (177)Lu complex while exhibiting a substantial increase in formation rate. The 1B4M-DOTAmay have potential for radioimmunotherapy applications.

Neuroprotective and neurotoxic properties of the 'inert' gas, xenon

BACKGROUND

Antagonists of the N-methyl-D-aspartate (NMDA) subtype of glutamate receptors have been shown not only to have neuroprotective effects but also to exhibit neurotoxic properties. In this study, we used c-Fos, a protein product of an immediate early gene, as a marker of neuronal injury to compare the neuroprotective effects of xenon and the neurotoxic properties of xenon, nitrous oxide, and ketamine, three anaesthetics with NMDA receptor antagonist properties.

METHODS

We used an in vivo rat model of brain injury in which N-methyl-DL-aspartic acid (NMA) is injected subcutaneously (s.c.) and c-Fos expression in the arcuate nucleus is used as a measure of injury. To examine the neurotoxic potential of each of the three anaesthetics with NMDA receptor antagonist properties, c-Fos expression in the posterior cingulate and retrosplenial (PC/RS) cortices was measured.

RESULTS

Xenon dose-dependently suppressed NMA-induced c-Fos expression in the arcuate nucleus with an IC(50) of 47 (2)% atm. At the highest concentration tested (75% atm) NMA-induced neuronal injury was decreased by as much as that observed with the prototypical NMDA antagonist MK801 (0.5 mg kg(-1) s.c.). Both nitrous oxide and ketamine dose-dependently increased c-Fos expression in PC/RS cortices; in contrast, xenon produced no significant effect. If the dopamine receptor antagonist haloperidol was given before either nitrous oxide or ketamine, their neurotoxic effects were eliminated.

CONCLUSIONS

Uniquely amongst anaesthetics with known NMDA receptor antagonist action, xenon exhibits neuroprotective properties without co-existing neurotoxicity. The reason why ketamine and nitrous oxide, but not xenon, produce neurotoxicity may involve their actions on dopaminergic pathways.

Applications of display technologies to proteomic analyses

With the rapid accumulation of genetic information, development of general experimental approach suitable for large scale annotation and profiling of the whole proteome have become one of the major challenges in postgenomic era. Biomolecular display technologies, which allow expressing of a large pool of modularly coded biomolecules, are extremely useful for accessing and analyzing protein diversity and interaction profile on a large scale. Recent advances in protein display technologies and their applications to proteomic analyses have been discussed.

Applications of yeast in drug discovery

The yeast Saccharomyces cerevisiae is perhaps the best-studied eukaryotic organism. Its experimental tractability, combined with the remarkable conservation of gene function throughout evolution, makes yeast the ideal model genetic organism. Yeast is a non-pathogenic model of fungal pathogens used to identify antifungal targets suitable for drug development and to elucidate mechanisms of action of antifungal agents. As a model of fundamental cellular processes and metabolic pathways of the human, yeast has improved our understanding and facilitated the molecular analysis of many disease genes. The completion of the Saccharomyces genome sequence helped launch the post-genomic era, focusing on functional analyses of whole genomes. Yeast paved the way for the systematic analysis of large and complex genomes by serving as a test bed for novel experimental approaches and technologies, tools that are fast becoming the standard in drug discovery research

Enzyme-mediated free radical polymerization of styrene

Horseradish peroxidase-mediated polymerization of styrene at ambient temperature is reported. Molecular weight and yield of polystyrene were influenced by solvent, concentration of hydrogen peroxide, and initiator (beta-diketones, coumarin). THF:H2O (v/v) and hydrogen peroxide (0.082 mol/L) provided maximum yield of polymer (21.2% weight conversion of styrene to polystyrene) with 2,4-pentanedione as initiator. 1,3-Cyclopentanedione and dibenzoylmethane as initiators resulted in higher yield of polymer (approximately 60%) and a higher molecular weight (Mn = 96,504, polydispersity = 2.16), respectively. This enzymatic strategy was also used for the synthesis of polymers from styrene derivatives, 4-methylstyrene and 2-vinylnaphthalene, the latter resulting in a > 90% yield of polymer. The presence of the initiators in the polymer chains is reported.

Radioimmunotherapy for model B cell malignancies using 90Y-labeled anti-CD19 and anti-CD20 monoclonal antibodies

In recent years, radioimmunotherapy (RIT) with beta(-) particle emitting radionuclides targeting the CD20 antigen on B cells in the treatment of non-Hodgkin's lymphoma has provided the most compelling human clinical data for the success of RIT. CD19, like CD20, is an antigen expressed on the surface of cells of the B lineage, and CD19 may provide an alternative target for radioimmunotherapy of B cell neoplasms. CD19 has been largely overlooked as a target for conventional 131I RIT, because the antigen rapidly internalizes upon binding of antibody, resulting in catabolism and significant release of 131I. Such modulation may be an advantage to RIT with radiometals such as 90Y, 177Lu, 213Bi and 225Ac. Herein, we have compared beta(-) particle RIT with antibodies targeting either CD19 or CD20. The anti-CD19 and anti-CD20 antibodies, B4 or C2B8, respectively, were appended with the SCN-CHX-A''-DTPA bifunctional chelating agent and labeled with 90Y. In the tumor model used, there were three times as many CD20 target sites on lymphoma cells as compared to CD19 sites (62000 vs 20000 binding sites, respectively). We compared the efficacy of the 90Y-labeled antibodies to reduce lymphoma in a nude mouse xenograft solid tumor model, after measurable lymphoma appeared. Reduction in tumor size began at day 3 in all three 90Y-treated groups, but tumor began to recur in many animals 9 days after the treatments. There was one cure in each specific treatment group. In contrast, the tumor in the two control groups showed no regression. There was a significant prolongation of median survival time from xenograft (P < 0.0001) in all the 90Y-labeled antibody construct-treated groups (32 days for 0.15 mCi 90Y-B4; 26 days for 0.20 mCi 90Y-C2B8, and 23 days for 0.15 mCi 90Y-C2B8) in comparison to the two control groups (11 days for 0.02 mg of C2B8 and 9 days for untreated growth controls). Specificity of the radioimmunotherapy was also shown. In conclusion, 90Y-labeled anti-CD19 antibody has efficacy comparable to 90Y-labeled anti-CD20 antibody in the treatment of mice bearing human lymphoma xenografts. These data suggest that CD19-targeted RIT merits further study.

Nuclear translocation of PDCD5 (TFAR19): an early signal for apoptosis?

The programmed cell death 5 (PDCD5) protein is a novel protein related to regulation of cell apoptosis. In this report, we demonstrate that the level of PDCD5 protein expressed in cells undergoing apoptosis is significantly increased compared with normal cells, then the protein translocates rapidly from the cytoplasm to the nucleus of cells. The appearance of PDCD5 in the nuclei of apoptotic cells precedes the externalization of phosphatidylserine and fragmentation of chromosome DNA. This phenomenon is parallel to the loss of mitochondrial membrane potential, independent of the feature of apoptosis-inducing stimuli and also independent of the cell types and the apoptosis modality. In conclusion, the nuclear translocation of PDCD5 is a universal earlier event of the apoptotic process, and may be a novel early marker for apoptosis.

Effect of sarsasapogenin and its derivatives on the stimulus coupled responses of human neutrophils

METHODS

The effects of three sapogenins (sarsasapogenin, tigogenin and hecogenin) on the stimulus-induced superoxide generation and protein tyrosyl phosphorylation in human neutrophils were investigated.

RESULTS

When the cells were preincubated with sapogenin, three sapogenins dose-dependently suppressed the superoxide generations induced by N-formyl-methionyl-leucyl-phenylalanine (fMLP) and phorbol 12-myristate 13-acetate (PMA), respectively. In both cases, their effects were in the order: sarsasapogenin>tigogenin>hecogenin. While sarsasapogenin suppressed the superoxide generation induced by arachidonic acid (AA) as well, the superoxide generation was scarcely suppressed by tigogenin and significantly enhanced by hecogenin. In parallel to their effects on the superoxide generation, the three sapogenins dose-dependently suppressed the fMLP-induced and PMA-induced tyrosyl phosphorylations of 45 kDa protein in neutrophils, respectively.

CONCLUSIONS

Of the sapogenins tested, sarsasapogenin may have the most clinical use as it suppresses superoxide generation.

Two-component method to enantiopure quinolizidinones and Indolizidinones. Total synthesis of (-)-lasubine II

The reaction of iodides 1 and enantiopure beta-amino esters 2 mediated by potassium carbonate in acetonitrile at 65 degrees C provides quinolizidinones or indolizidinones 3, together with piperidines or pyrrolidines 4. Hydrolysis of 4 to the corresponding carboxylic acids followed by treatment of acetic anhydride/triethylamine gives 3 in high yields. Using 3a as a key intermediate, (-)-lasubine II is synthesized in four steps. [reaction: see text]

Tumor therapy with targeted atomic nanogenerators

A single, high linear energy transfer alpha particle can kill a target cell. We have developed methods to target molecular-sized generators of alpha-emitting isotope cascades to the inside of cancer cells using actinium-225 coupled to internalizing monoclonal antibodies. In vitro, these constructs specifically killed leukemia, lymphoma, breast, ovarian, neuroblastoma, and prostate cancer cells at becquerel (picocurie) levels. Injection of single doses of the constructs at kilobecquerel (nanocurie) levels into mice bearing solid prostate carcinoma or disseminated human lymphoma induced tumor regression and prolonged survival, without toxicity, in a substantial fraction of animals. Nanogenerators targeting a wide variety of cancers may be possible.