Multiple Sclerosis Severity Scale and whole-brain N-acetylaspartate concentration for patients' assessment

BACKGROUND

The ability to predict the course of multiple sclerosis (MS) is highly desirable but lacking.

OBJECTIVE

To test whether the MS Severity Scale (MSSS) and global neuronal viability, assessed through the quantification of the whole-brain N-acetylaspartate concentration (WBNAA), concur or complement the assessment of individual patients' disease course.

METHODS

The MSSS and average WBNAA loss rate (ΔWBNAA, extrapolated based on one current measurement and the assumption that at disease onset neural sparing was similar to healthy controls, obtained with proton magnetic resonance (MR) spectroscopy and magnetic resonance imaging (MRI)) from 61 patients with MS (18 male and 43 female) with long disease duration (15 years or more) were retrospectively examined. Some 27 patients exhibited a 'benign' disease course, characterized by an Expanded Disability Status Scale score (EDSS) of 3.0 or less, and 34 were 'non-benign': EDSS score higher than 3.0.

RESULTS

The two cohorts were indistinguishable in age and disease duration. Benign patients' EDSS and MSSS (2.1 ± 0.7, 1.15 ± 0.60) were significantly lower than non-benign (4.6 ± 1.0, 3.6 ± 1.2; both p < 10(-4)). Their respective average ΔWBNAA, 0.10 ± 0.16 and 0.11 ± 0.12 mM/year, however, were not significantly different (p > 0.7). While MSSS is both sensitive to (92.6%) and specific for (97.0%) benign MS, ΔWBNAA is only sensitive (92.6%) but not specific (2.9%).

CONCLUSION

Since the WBNAA loss rate is similar in both phenotypes, the only difference between them is their clinical classification, characterized by MSSS and EDSS. This may indicate that 'benign' MS probably reflects fortuitous sparing of clinically eloquent brain regions and better utilization of brain plasticity.

Discovery of PH-797804, a highly selective and potent inhibitor of p38 MAP kinase

The synthesis and SAR studies of a novel N-aryl pyridinone class of p38 kinase inhibitors are described. Systematic structural modifications to the HTS lead, 5, led to the identification of (-)-4a as a clinical candidate for the treatment of inflammatory diseases. Additionally, the chiral synthesis and properties of (-)-4a are described.

A network approach to assessing cognition in disorders of consciousness

OBJECTIVE

Conventional assessments of consciousness rely on motor responses to indicate awareness. However, overt behaviors may be absent or ambiguous in patients with disorders of consciousness (DOC) resulting in underrating capacity for cognition. fMRI during a silent picture-naming task was evaluated as an indicator of command following when conventional methods are not sufficient.

METHODS

A total of 10 patients with and without conventional evidence of awareness, who met diagnostic criteria for the minimally conscious state (MCS) (n = 5), vegetative state (VS) (n = 3), emerged from MCS (EMCS) (n = 1), and locked-in syndrome (LIS) (n = 1), participated in this observational fMRI study.

RESULTS

The LIS and EMCS patients engaged a complete network of essential language-related regions during the object-naming task. The MCS and 2 of the VS patients demonstrated both complete and partial preservation of the object-naming system. Patients who engaged a complete network scored highest on the Coma Recovery Scale-Revised.

CONCLUSIONS

This study supports the view that fMRI during object naming can elicit brain activations in patients with DOC similar to those observed in healthy subjects during command following, and patients can be stratified by completeness of the engaged neural system. These results suggest that activity of the language network may serve as an indicator of high-level cognition and possibly volitional processes that cannot be discerned through conventional behavioral assessment alone.

The role of adipose cell size and adipose tissue insulin sensitivity in the carbohydrate intolerance of human obesity

Glucose metabolism and insulin sensitivity of isolated human adipose tissue was studied as a function of adipose cell size and number. Glucose metabolism by these tissues was closely related to the number of cells in the fragment, irrespective of cell size. Adipose cells of obese individuals metabolized glucose to carbon dioxide and triglyceride at rates similar to adipose cells of nonobese subjects. In contrast, insulin responsiveness of adipose tissue was dependent upon adipose cell size. The larger its adipose cells the less insulin sensitive was the tissue. Thus, adipose tissue of obese subjects, with enlarged cells, showed a diminished response to insulin. After weight loss and reduction in adipose cell size, insulin sensitivity of the adipose tissue of obese patients was restored to normal. When adipose tissue of obese individuals showed impaired responsiveness to insulin, their plasma insulin levels, after oral glucose, were elevated. Weight loss and reduction in adipose cell size restored plasma insulin concentration to normal, concomitant with the return of normal tissue insulin sensitivity.

SD0006: a potent, selective and orally available inhibitor of p38 kinase

SD0006 is a diarylpyrazole that was prepared as an inhibitor of p38 kinase-alpha (p38alpha). In vitro, SD0006 was selective for p38alpha kinase over 50 other kinases screened (including p38gamma and p38delta with modest selectivity over p38beta). Crystal structures with p38alpha show binding at the ATP site with additional residue interactions outside the ATP pocket unique to p38alpha that can confer advantages over other ATP competitive inhibitors. Direct correlation between inhibition of p38alpha activity and that of lipopolysaccharide-stimulated TNFalpha release was established in cellular models and in vivo, including a phase 1 clinical trial. Potency (IC(50)) for inhibiting tumor necrosis factor-alpha (TNFalpha) release, in vitro and in vivo, was <200 nmol/l. In vivo, SD0006 was effective in the rat streptococcal-cell-wall-induced arthritis model, with dramatic protective effects on paw joint integrity and bone density as shown by radiographic analysis. In the murine collagen-induced arthritis model, equivalence was demonstrated to anti-TNFalpha treatment. SD0006 also demonstrated good oral anti-inflammatory efficacy with excellent cross-species correlation between the rat, cynomolgus monkey, and human. SD0006 suppressed expression of multiple proinflammatory proteins at both the transcriptional and translational levels. These properties suggest SD0006 could provide broader therapeutic efficacy than cytokine-targeted monotherapeutics.

Deleted in cancer 1: Search for a function in prostate cancer

e16095

Background: Deleted In Cancer 1 (DICE1/INTS6) gene was recently identified to colocalize with the microsatellite marker D13S284 in 13q14.3, a region frequently affected by allelic deletion in many solid tumors including prostate cancer (PrCa). DICE1 missense mutations have been previously detected in PrCa cell line LNCap, and reduced DICE1 expression appears to be associated with CpG promoter hypermethylation in PrCa cells. DICE1 is a highly conserved nuclear protein suggesting its involvement in DNA repair, transcription, or RNA splicing. In mouse, the DICE1 homologue interferes with the response to insulin-like growth factor 1 and suppresses anchorage-independent growth of transformed mouse cells. The totality of these results suggests that DICE1 is a tumor suppressor gene and insist on the need to better characterize DICE1 function in PrCa. Methods: Expression of DICE1 was evaluated by Northern Blot in PrCa cell lines LNCap, DU145, PC3, PC3ml and CPTX1532 and compared to expression level in normal prostate cell line NPTX1532. DICE1 growth inhibitory effects were analyzed by colony formation assay on PC3 and DU145 cells transfected with DICE1 expression plasmid or control vector. Apoptosis was assessed by visualization of genomic DNA fragmentation on agarose gel. PCR arrays (SABiosciences) were used to identify specific signaling pathways modulated in response to DICE1 expression. Results: Markedly decreased DICE1 mRNA levels were detected in PrCa cell lines LNCap, DU145, PC3 and PC3ml as well as CPTX1532 as compared to NPTX1532, a cell line derived from normal prostate tissue. Ectopic expression of DICE1 cDNA in DU145 and PC3 cells substantially suppressed their ability to form colonies in vitro. This growth inhibition was not due to immediate induction of apoptosis suggesting growth suppression by other pathways. Expression profiling identified multiple pathways, such as Wnt, Hedgehog, PI-3 Kinase, NFκB and Insulin pathways, regulated in response to ectopic DICE1 expression. Furthermore, various transcription factors including Fos, Jun, CEBPA and PPAR-γ were up-regulated in response to DICE1. Conclusions: These results clearly illustrate the growth inhibitory ability of DICE1 in PrCa. Expression profiling links DICE1 function to growth factor signaling and cell-cell communication.

No significant financial relationships to disclose.

Relating functional changes during hand movement to clinical parameters in patients with multiple sclerosis in a multi-centre fMRI study

We performed a prospective multi-centre study using functional magnetic resonance imaging (fMRI) to better characterize the relationships between clinical expression and brain function in patients with multiple sclerosis (MS) at eight European sites (56 MS patients and 60 age-matched, healthy controls). Patients showed greater task-related activation bilaterally in brain regions including the pre- and post-central, inferior and superior frontal, cingulate and superior temporal gyri and insula (P < 0.05, all statistics corrected for multiple comparisons). Both patients and healthy controls showed greater brain activation with increasing age in the ipsilateral pre-central and inferior frontal gyri (P < 0.05). Patients, but not controls, showed greater brain activation in the anterior cingulate gyrus and the bilateral ventral striatum (P < 0.05) with less hand dexterity. An interaction between functional activation changes in MS and age was found. This large fMRI study over a broadly selected MS patient population confirms that movement for patients demands significantly greater cognitive 'resource allocation' and suggests age-related differences in brain responses to the disease. These observations add to evidence that brain functional responses (including potentially adaptive brain plasticity) contribute to modulation of clinical expression of MS pathology and demonstrate the feasibility of a multi-site functional MRI study of MS.

Quantitative objective markers for upper and lower motor neuron dysfunction in ALS

OBJECTIVE

To investigate the value of objective biomarkers for upper (UMN) and lower (LMN) motor neuron involvement in ALS.

METHODS

We prospectively studied 64 patients with ALS and its subsets using clinical measures, proton MR spectroscopic imaging ((1)H MRSI), diffusion tensor imaging, transcranial magnetic stimulation, and the motor unit number estimation (MUNE) at baseline and every 3 months for 15 months and compared them with control subjects.

RESULTS

(1)H MRSI measures of the primary motor cortex N-acetyl-aspartate (NAA) concentration were markedly reduced in ALS (p = 0.009) and all UMN syndromes combined (ALS, familial ALS [fALS], and primary lateral sclerosis; p = 0.03) vs control values. Central motor conduction time to the tibialis anterior was prolonged in ALS (p < 0.0005) and combined UMN syndromes (p = 0.001). MUNE was lower in ALS (p < 0.0005) and all LMN syndromes combined (ALS, fALS, and progressive muscular atrophy; p = 0.001) vs controls. All objective markers correlated well with the ALS Functional Rating Scale-Revised, finger and foot tapping, and strength testing, suggesting these markers related to disease activity. Regarding changes over time, MUNE changed rapidly, whereas neuroimaging markers changed more slowly and did not significantly differ from baseline.

CONCLUSIONS

(1)H MR spectroscopic imaging measures of the primary motor cortex N-acetyl-aspartate (NAA) concentration and ratio of NAA to creatine, central motor conduction time to the tibialis anterior, and motor unit number estimation significantly differed between ALS, its subsets, and control subjects, suggesting they have potential to provide insight into the pathobiology of these disorders.

Phosphate deficiency promotes modification of iron distribution in Arabidopsis plants

Phosphate (Pi) is an essential element for plant development and metabolism. Due to its low availability and mobility in soils, it is often a limiting nutrient for their growth. This phenomenon is reinforced by the formation of insoluble complexes in the environment with many cations, affecting the solubility of both phosphate and associated ions. This interaction is investigated here for iron, a strong phosphate chelator. Depleting the medium in phosphate clearly resulted in an increase of iron content in Arabidopsis. These modifications triggered molecular responses linked with iron status (transport, homeostasis and accumulation). Interestingly, physiological modifications affecting iron storage were also observed. The accumulation of phosphate/iron complexes in the vacuoles of plants grown in Pi-rich medium disappeared in Pi-depleted medium in favor of accumulation of iron inside the chloroplasts, likely associated with ferritin.

Structure-function relationships in the human visual system using DTI, fMRI and visual field testing: pre- and post-operative assessments in patients with anterior visual pathway compression

The focus of this project is to improve our understanding of the relationships between brain structure and function in patients presenting with anterior visual pathway compression using functional MRI (fMRI), visual field(VF) maps and diffusion tensor imaging (DTI). Significant visual loss can occur when large pituitary lesions compress the optic chiasm. Surgical resection of these lesions decompresses the chiasm and can lead to visual recovery. In this preliminary study, we selected patients presenting with slowly progressive visual loss secondary to a compressive pituitary region mass. Using preoperative DTI data, we reconstructed white matter projections of the optic radiations and demonstrated a structural correlation with functional vision as quantified by formal visual field mapping and fMRI. The structural data generated through a fiber tracking algorithm may represent a potentially powerful tool to better understand functional visual deficits in patients with anterior visual pathway compression. Furthermore, we believe that specific patterns in preoperative DTI data may predict the likelihood of postoperative visual recovery in a select group of patients.

fMRI reveals large-scale network activation in minimally conscious patients

BACKGROUND

The minimally conscious state (MCS) resulting from severe brain damage refers to a subset of patients who demonstrate unequivocal, but intermittent, behavioral evidence of awareness of self or their environment. Although clinical examination may suggest residual cognitive function, neurobiological correlates of putative cognition in MCS have not been demonstrated.

OBJECTIVE

To test the hypothesis that MCS patients retain active cerebral networks that underlie cognitive function even though command following and communication abilities are inconsistent.

METHODS

fMRI was employed to investigate cortical responses to passive language and tactile stimulation in two male adults with severe brain injuries leading to MCS and in seven healthy volunteers.

RESULTS

In the case of the patient language-related tasks, auditory stimulation with personalized narratives elicited cortical activity in the superior and middle temporal gyrus. The healthy volunteers imaged during comparable passive language stimulation demonstrated responses similar to the patients' responses. However, when the narratives were presented as a time-reversed signal, and therefore without linguistic content, the MCS patients demonstrated markedly reduced responses as compared with volunteer subjects, suggesting reduced engagement for "linguistically" meaningless stimuli.

CONCLUSIONS

The first fMRI maps of cortical activity associated with language processing and tactile stimulation of patients in the minimally conscious state (MCS) are presented. These findings of active cortical networks that serve language functions suggest that some MCS patients may retain widely distributed cortical systems with potential for cognitive and sensory function despite their inability to follow simple instructions or communicate reliably.

[Activation of granulocytes and antiproteases in open heart surgery]

OBJECTIVE

Cardiovascular surgical procedures with extracorporeal circulation (ECC) lead to neutrophil activation followed by the release of proteases such as neutrophil elastase (NE) and oxidants. The mis-balance between proteases and their physiological inhibitors may contribute to morbidity in the postoperative period. In this study, the effects of cardiac surgery on neutrophil mediators were evaluated. Release of neutrophil elastase and plasma levels of the natural NE antagonists alpha (1)-proteinase inhibitor (API) and secretory leukocyte proteinase inhibitor (SLPI) were measured. The oxidative burst and the phagocytic activity were also evaluated. Tissue destruction was quantified by measuring the serum concentration of fibronectin.

METHODS

Blood samples were obtained from 30 patients undergoing elective coronary artery bypass grafting (n = 30). NE and SLPI concentrations were measured by ELISA, API and fibronectin plasma levels were determined by nephelometry. Neutrophil phagocytic activity and oxidative burst were evaluated by flow cytometry.

RESULTS

Neutrophil elastase plasma concentrations rose during ECC (245 +/- 107 microg/ml versus 44 +/- 14 microg/ml after induction, p < 0.001), whereas SLPI and API were decreased after onset of ECC. 24 h after ECC SLPI (54 +/- 17 ng/ml versus 41 +/- 10 ng/ml, p < 0.05) and API (3 +/- 0.5 g/l versus 1.6 +/- 0.3 g/l, p < 0.05) increased significantly compared to baseline values. A minor increase in phagocytic activity was observed after the onset of ECC. There were no significant changes in the oxidative burst.

CONCLUSION

Cardiac surgery with ECC leads to neutrophil activation and elastase release. The imbalance between NE and the NE inhibitors API and SLPI may increase the risk for tissue damage due to granulocyte activation after cardiac surgery.

Clinical and biochemical manifestations and molecular characterization of the mutation HPRT Jerusalem

A novel point mutation (I137T) was identified in the hypoxanthine-guanine phosphoribosyltransferase (HPRT) encoding gene, in a patient with partial deficiency of the enzyme. The mutation, ATT to ACT (substitution of isoleucine to threonine), occurred at codon 137, which is within the region encoding the binding site for 5-phosphoribosyl-1-pyrophosphate (PRPP). The mutation caused decreased affinity for PRPP, manifested clinically as a Lesch-Nyhan variant (excessive purine production and delayed acquisition of language skills). The partial HPRT deficiency could be detected only by measuring HPRT activity in intact fibroblasts (uptake of hypoxanthine into nucleotides).