Characterization of detergent-insoluble proteins in ALS indicates a causal link between nitrative stress and aggregation in pathogenesis

Background

Amyotrophic lateral sclerosis (ALS) is a progressive and fatal motor neuron disease, and protein aggregation has been proposed as a possible pathogenetic mechanism. However, the aggregate protein constituents are poorly characterized so knowledge on the role of aggregation in pathogenesis is limited.

Methodology/Principal Findings

We carried out a proteomic analysis of the protein composition of the insoluble fraction, as a model of protein aggregates, from familial ALS (fALS) mouse model at different disease stages. We identified several proteins enriched in the detergent-insoluble fraction already at a preclinical stage, including intermediate filaments, chaperones and mitochondrial proteins. Aconitase, HSC70 and cyclophilin A were also significantly enriched in the insoluble fraction of spinal cords of ALS patients. Moreover, we found that the majority of proteins in mice and HSP90 in patients were tyrosine-nitrated. We therefore investigated the role of nitrative stress in aggregate formation in fALS-like murine motor neuron-neuroblastoma (NSC-34) cell lines. By inhibiting nitric oxide synthesis the amount of insoluble proteins, particularly aconitase, HSC70, cyclophilin A and SOD1 can be substantially reduced.

Conclusion/Significance

Analysis of the insoluble fractions from cellular/mouse models and human tissues revealed novel aggregation-prone proteins and suggests that nitrative stress contribute to protein aggregate formation in ALS.

Rapid palatal expansion in patients with craniosynostosis: a case report

The craniosynostoses represent a group of pathologies characterised by the premature fusion (during prenatal or perinatal stages or early infancy) of one or more of the cranial sutures. Its genetic origins are not completely clear although mutations in the genes that code for fibroblast growth factor receptors have been described; depending upon the gene involved, the type of mutation and the embryological period in which the mutation itself occurs, a type of craniosynostosis arises that may involve one or more cranial sutures. The premature fusion results in a lack of growth in the regions corresponding to the cranial vaults, with compensatory growth occurring in other regions and the consequent deformation of the skull. Here, a case report is presented of a Caucasian male child affected by craniostenosis of the sagittal suture with a orthodontic-orthopedic diagnosed ogival palate and insufficient space for the eruption of the superior canines. The patient was treated by fitting a rapid palatal protractor, an orthopedic device that acts upon the median palatine suture of the palate increasing the transverse diameter of the upper jaw and causes the widening and lowering of the floor of the nasal cavity. The results obtained were equivalent to those obtained in subjects with no past medical history of craniosynostosis. This clinical study demonstrated that the premature fusion of the mid-sagittal suture of the skull, that characterises sagittal craniosynostoses, can occur without the involvement of the median suture of the palate, rendering expansion possible by means of orthopedic treatment.

Adaptation to G93Asuperoxide dismutase 1 in a motor neuron cell line model of amyotrophic lateral sclerosis: the role of glutathione

Motor neuron degeneration in amyotrophic lateral sclerosis involves oxidative damage. Glutathione (GSH) is critical as an antioxidant and a redox modulator. We used a motor neuronal cell line (NSC-34) to investigate whether wild-type and familial amyotrophic lateral sclerosis-linked G93A mutant Cu,Zn superoxide dismutase (wt/G93ASOD1) modified the GSH pool and glutamate cysteine ligase (GCL), the rate-limiting enzyme for GSH synthesis. We studied the effect of various G93ASOD1 levels and exposure times. Mutant Cu,Zn superoxide dismutase induced an adaptive process involving the upregulation of GSH synthesis, even at very low expression levels. However, cells with a high level of G93ASOD1 cultured for 10 weeks showed GSH depletion and a decrease in expression of the modulatory subunit of GCL. These cells also had lower levels of GSH and GCL activity was not induced after treatment with the pro-oxidant tert-butylhydroquinone. Cells with a low level of G93ASOD1 maintained higher GSH levels and GCL activity, showing that the exposure time and the level of the mutant protein modulate GSH synthesis. We conclude that failure of the regulation of the GSH pathway caused by G93ASOD1 may contribute to motor neuron vulnerability and we identify this pathway as a target for therapeutic intervention.

Giant noise amplification in synchronously pumped optical parametric oscillators

We show numerically that a synchronously pumped optical parametric oscillator can show giant noise amplification of the order of 10(9). We use pseudospectra to identify the parameter region for giant noise amplification and to estimate its magnitude.

State dependent pseudoresonances and excess noise

We show that strong response to nonresonant modulations and excess noise are state dependent in generic nonlinear systems; i.e., they affect some output states but are absent from others. This is demonstrated in complex Swift-Hohenberg models relevant to optics, where it is caused by the non-normality of the linearized stability operators around selected output states, even though the cavity modes are orthogonal. In particular, we find the effective parameters that control excess noise and the response to modulations and show cases where these phenomena are enhanced by an order of magnitude.

Tracking spatial modes in nearly hemispherical microcavities

We measure experimentally the spatial intensity profiles and resonant frequencies of the transverse modes of nearly hemispherical microcavities with cavity length and mirror curvatures below 10 microm. These resonators possess axially symmetric Gauss-Laguerre-like modes, but do not display the frequency degeneracies typical of large-scale optical cavities. It is possible to interpret these results using a paraxial model of cavity propagation that includes nonparabolic optical elements.

Control of topological defects in microstructured liquid crystal cells

We study how the propagation of light inside recently developed micro-structured cells, can be actively tuned by polarising the nanoscale defects in the nematic liquid crystals they contain. Our 'planar-spherical' cells are formed by assembling a planar and a gold-coated hemispherical micro-mirror. Optical reflection images of the back-reflected polarised light show a remarkable change of symmetry as a function of the voltage applied to the cell. Theoretical models of the alignment of the liquid crystal within the cell indicate that the constraints imposed on the liquid crystal by the cell geometry and by the applied electric field induces the formation of defects. Their motion under the effect of the applied electric field is responsible for the change of symmetry of the back-reflected light. Furthermore, experimental measurements of the relaxation time of the back-reflected intensity indicate that the motion of the defect in our micro-structured cells is much faster than in equivalent planar cells.

Average patterns and coherent phenomena in wide aperture lasers

Using a realistic model of wide aperture, weakly astigmatic lasers we develop a framework to analyze experimental average intensity patterns. We use the model to explain the appearance of patterns in terms of the modes of the cavity and to show that the breaking of the symmetry of the average intensity patterns is caused by overlaps in the frequency spectra of nonvanishing of modes with different parity. This result can be used even in systems with very fast dynamics to detect experimentally overlaps of frequency spectra of modes.

Association between HLA class II antigens and hepatitis C virus infection

The aim was to confirm the influence of HLA Class II antigens on the progression of HCV infection and to assess the relationship between these antigens and histological damage, HCV viral load and HCV genotype. 143 patients were enrolled and divided into three groups. Group A included 34 anti-HCV positive, HCV-RNA negative patients with ALT persistently normal; group B included 39 patients with HCV-RNA positive and abnormal ALT level; group C included 70 normal subjects. Serological HCL typing was performed with lymphocytotoxicity test by Terasaky and McClelland, using lymphobeads HLC class II. The frequency of HLA DR11 (5) was significantly higher in the control group (52.9%) and in group A (64.7%), than in group B (28.2%). Allele HLA DR6 was demonstrated in a similar proportion (26%) among control group and group B, while HLA DR14 (6) was less frequent among controls (18% vs 1.4%). In group A the frequency of HLA DR14 (6) was 3% compared to group B, HLA DR17 (3) was prevalent (15.4%) in group B. Liver damage was associated with the detection of HLA DR14 (6) and HLD DR17 (3) antigens. Significantly lower levels of HCV-RNA were measured in subjects with HLA DR11 (5) than in these with either DR6 or DR17 (3). HLA class II antigens appear crucial for resolution or progression of HCV hepatitis. The punctual identification of these genetic factors may, therefore, prove to be useful in predicting disease evolution, in guiding the appropriate therapy for patients with poor prognosis, and in encouraging the development of now therapeutic strategies.

Epidemiology of primary intracranial tumours in NW Italy, a population based study: stable incidence in the last two decades

Data about the epidemiology of primary intracranial tumours (PIT) are still heterogeneous depending on different methodological approach in collecting data. In Valle d' Aosta, north west side of Italy, we have carried out a prospective consecutive population based study to calculate the incidence of PIT in the last decade (1992-1999) and to compare these rates with the previous period (1986-1991), data reported in a previous paper. The mean annual PIT incidence rate (ri) per 100,000 inhabitants was 25.48. The mean annual incidence rates in the two period of comparison were adjusted to the 1991 Italian population by the direct method. The standardised ratio was 26.43 in the previous period and 23.24 in the second decade. There is no statistically significant difference. The mean annual PIT incidence rates by tumour types were meningiomas 13.27/100,000 (men 9.77; women 16.7), neuroepithelial group 9.3 (men 10.62; women 8.1), adenomas 1.26, neurinomas 0.7. Mean annual incidence rates by tumour class were also stable. The stable incidence rate in the two periods and the similar incidence in England (21.04/100,000 person year), strengthen the evidence for a stable incidence rate of PIT in the last decade. These three papers used similar methodology. The homogeneous methodology allows comparison and further evaluation.

Morphometric modeling of olfactory circuits in the insect antennal lobe: I. Simulations of spiking local interneurons

Inhibitory local interneurons (LNs) play a critical role in shaping the output of olfactory glomeruli in both the olfactory bulb of vertebrates and the antennal lobe of insects and other invertebrates. In order to examine how the complex geometry of LNs may affect signaling in the antennal lobe, we constructed detailed multi-compartmental models of single LNs from the sphinx moth, Manduca sexta, using morphometric data from confocal-microscopic images. Simulations clearly revealed a directionality in LNs that impeded the propagation of injected currents from the sub-micron-diameter glomerular dendrites toward the much larger-diameter integrating segment (IS) in the coarse neuropil. Furthermore, the addition of randomly-firing synapses distributed across the LN dendrites (simulating the noisy baseline activity of afferent input recorded from LNs in the odor-free state) led to a significant depolarization of the LN. Thus the background activity typically recorded from LNs in vivo could influence synaptic integration and spike transformation in LNs through voltage-dependent mechanisms. Other model manipulations showed that active currents inserted into the IS can help synchronize the activation of inhibitory synapses in glomeruli across the antennal lobe. These data, therefore, support experimental findings suggesting that spiking inhibitory LNs can operate as multifunctional units under different ambient odor conditions. At low odor intensities, (i.e. subthreshold for IS spiking), they participate in local, mostly intra-glomerular processing. When activated by elevated odor concentrations, however, the same neurons will fire overshooting action potentials, resulting in the spread of inhibition more globally across the antennal lobe. Modulation of the passive and active properties of LNs may, therefore, be a deciding factor in defining the multi-glomerular representations of odors in the brain.

Thyrotoxic periodic paralysis in a Caucasian man in treatment for Graves' disease

Thyrotoxic periodic paralysis (TPP) is the main secondary form of hypokalemic periodic paralysis and is mostly associated with Graves' disease. Initially diagnosed in Asian countries, TPP has been sporadically reported in different populations of the Western World. Increased Na+/K(+)-ATPase activity seems to be responsible for the marked hypokalemia observed during the transient paralysis attacks. We report on a 35-year-old Italian man without history of hypokalemic periodic paralysis and hyperthyroidism, in treatment for Graves' disease, who suffered episodes of flaccid paralysis even with normal thyroid hormone levels. An insulin-glucose provocation test confirmed our diagnosis. Oral and parenteral potassium reverse the symptoms. Monitoring of thyroid function is also important to prevent further attacks.

Temporal trends of stroke in Valle d'Aosta, Italy. Incidence and 30-day fatality rates

The objective of this study was to evaluate temporal changes of stroke in an Italian community by comparing the present incidence rates with those reported in the same area for 1989. The two studies were conducted by the same research group and met almost all the criteria proposed for an "ideal" stroke incidence study. The annual incidence rate per 1000 inhabitants increased (p < 0.01) by 29%, from 2.23 (95% CL, 1.96-2.50) in 1989 to 2.89 (95% CL, 2.58-3.20) in 1997. No statistically significant change was found when these rates were adjusted to the 1991 Italian population. The overall incidence rate was 2.40 (95% CL, 2.14-2.66) in 1989 and 2.65 (95% CL, 2.39-2.91) in 1997. The thirty-day case fatality rate declined dramatically (p < 0.001) from 31% (95% CL, 26-36) to 20% (95% CL, 16-24) between 1989 and 1997. Ageing of the population and better identification of cases could explain the high incidence rate, whereas the decrease of fatality rate may be due to a general improvement in acute care and inclusion of milder cases.

Prevention of cardioembolic stroke: use of oral anticoagulants in patients with atrial fibrillation

With the aim of quantifying the use of oral anticoagulant (OA) therapy in clinical practice, we surveyed 150 consecutive patients admitted with a diagnosis of atrial fibrillation (AF). Each patient was administered a questionnaire relating to the classic vascular risk factors and to the antithrombotic treatment received at home. The diagnosis of AF was formulated at the time of admission in 45 cases. Of the 105 cases with a previous diagnosis, OA therapy was relatively or absolutely contraindicated in 21 patients (20%), whereas the other 84 (80%) were ideal candidates for the treatment. Of these, 20 (24%) were actually receiving OA, 16 (19%) were on platelet anti-aggregants (PA), and 48 (57%) were receiving no antithrombotic treatment at all. Even lower percentages of OA use were found in the patients with a previous (20%) or recent (16%) history of cerebral ischemia. Upon discharge, of the 115 patients without contraindications to OA (84 with previously known and 31 with newly diagnosed AF), 50% were receiving OA and 20% PA. The results of this survey show that OA therapy is little used in the Valle d'Aosta Region for the prevention of ischemic stroke in AF patients at high risk for cerebral ischemia. The lack of knowledge among the general population, the difficulty of initiating the therapy in patients such as ours with severe comorbidities, and the absence of disorganization of centers for OA monitoring may be the main reasons underlying this low level of use. Population screening or a sensitization campaign could increase the identification of subjects at risk, whereas better organization of coagulation monitoring centers could encourage OA use in subjects at high risk for cerebral ischemia.

[Epidemiology and chronorhythmicity of recurrences of attempted suicide]

The authors examine cases of attempted suicide admitted to Hospital of Foggia from 1 January 1990 to 31 December 1996. They describe characteristics of repeaters. A total of 611 episodes of attempted suicide regarding 552 different subjects were observed during the study period. Women attempted suicide more than men. No significant difference was observed for age and repeaters between men and women; while women outnumbered men in cases of single episode. Attempted suicide showed a circadian rhythm for both in first-event cases and repeaters; against, circaseptan and circannual periodicity were not present in both groups. Women had a greatest risk of an other repetition after a free period from events, in fact the time between the first and the latest episode was greater for women than for men. Commonly, the repeaters attempted at suicide again making use of the same method used for the first episode.

The utility and cost-effectiveness of D-dimer measurements in the diagnosis of deep vein thrombosis

BACKGROUND AND OBJECTIVE

The potential utility of D-dimer measurements for the diagnosis of deep vein thrombosis became evident soon after the development of reliable commercial assays. The purpose of this review is to outline some critical aspects affecting cost-effectiveness of D-dimer measurements in the diagnosis of deep vein thrombosis (DVT).

METHODS

The authors have been working in this field contributing original papers whose data have been used for this study. In addition, the material analyzed in this article includes papers published in the journals covered by the Science Citation Index and Medline.

RESULTS

D-dimer levels are very sensitive to the process of fibrin formation/dissolution occurring with ongoing thrombosis. However, they may not be highly specific for venous thromboembolism as they are influenced by the presence of comorbid conditions potentially elevating plasma D-dimer (cancer, surgery, infectious diseases). In addition, commercially available ELISA assays, although quantitative and reproducible, cannot be used under emergency conditions because they are time-consuming and suited for batch-processing of plasma samples. Recently, new assays have been introduced which permit fast and quantitative D-dimer estimations in individual patients. We have evaluated the utility of two new rapid assays (LPIA D-dimer. Mitsubishi, and VIDAS D-DIMER, bio-Merieux) in combination with compression real-time-B-mode ultrasonography for the detection of deep vein thrombosis in asymptomatic patients following elective hip replacement and in patients with clinically suspected deep vein thrombosis. In both settings, we identified cut-off values with optimal sensitivity which allow exclusion of deep vein thrombosis in a considerable percentage of patients, with substantial sparing of economic resources. In fact, based on a cost-effectiveness analysis, a diagnostic algorithm combining D-dimers measurement and compression ultrasonography would result in cost-savings ranging from 5% to 55% in patients with high or low clinical pretest probability respectively. However, the specificity of D-dimer measurements for deep vein thrombosis was much higher in symptomatic than in asymptomatic patients. Choice of the cut-off value proved to be dependent on the method as well as on the patient populations studied.

CONCLUSIONS

The cost-effectiveness of D-dimers measurement in the diagnosis of asymptomatic DVT remains questionable. Conversely, our data strongly support the utility of D-dimers determinations in the diagnosis of symptomatic DVT. In terms of sparing economic resources, the introduction in the clinical laboratory of the rapid quantitative assays would be highly convenient, because they avoid a source of bias in the interpretation of D-dimers results, are easy to perform and do not require dedicated personnel or instrumentation. Prospective management studies validating the utility of D-dimer measurement in the diagnosis of deep vein thrombosis are urgently needed.

[A proposed work sheet for occupational therapy treatment]

The authors propose a new data sheet for occupational therapy treatment based on a classification of the operative areas and the use of graphic symbols related to the patient's degree of autonomy and to the possible utilization of aids. The use of graphic symbols is aimed at making the selection of operative areas as well as the occupational therapy treatment programme easier and swifter. The degree of required aid is described by a letter code, particularly for those needed in A.D.L. The easy reading of sheet and work plan should be of valuable help both in patients treatment and in the statistical evaluation.

Evaluation of a new rapid quantitative D-dimer assay in patients with clinically suspected deep vein thrombosis

The sensitivity and specificity for deep vein thrombosis (DVT) of a new rapid, quantitative and precise (total imprecision < 10%) D-dimer assay suitable for individual measurements (VIDAS D-DIMER, bio-Mérieux, France) were evaluated in a consecutive series of 103 in- and out-patients submitted to serial compression ultrasonography (C-US) for the clinical suspicion of DVT (n = 66) or of DVT recurrence (n = 37) and symptoms lasting from 1 to 15 days. DVT was found in 22 patients at baseline testing and no patient with an initially negative C-US developed vein incompressibility at follow up. The time elapsed from the onset of symptoms was negatively associated with D-dimer levels both in patients with and in those without DVT. In the entire series of patients, the sensitivity of a positive D-dimer test ( > or = 1.0 microgram/ml) for the presence of DVT was 96% (21/22 patients, 95% confidence interval 75-100%) with a specificity of 75% (64-84%), a negative predictive value of 98% (90-100%), a positive predictive value of 51% (35-67%), and an overall accuracy of 80% (70-87%). A normal D-dimer value (0.22 microgram/ml) was observed in one patient with DVT and symptoms lasting from 15 days. The approach of withholding C-US testing in patients with symptoms lasting from less than 11 days and D-dimer levels below the cut-off value was compared to serial C-US testing alone in a cost-effectiveness analysis subdividing the 66 patients with a first episode according to their clinical pretest probability of DVT. Thrombosis was detected in 6.7% of the patients in the low probability group (n = 15), 16.7% of the patients in the moderate probability group (n = 24), 51.9% of the patients in the high probability group (n = 27) and 8.1% of patients with suspected DVT recurrence. Calculated cost-savings for each DVT diagnosed ranged from 5% in the high pretest probability group to 55% in the low pretest probability group and to 77% in patients with suspected DVT recurrence. The safety of avoiding C-US testing in symptomatic patients with a negative D-dimer test should be evaluated in clinical management studies.

Hereditary ataxias and paraplegias in Valle d'Aosta, Italy: a study of prevalence and disability

INTRODUCTION

a study was conducted in the Valle d'Aosta Region, Italy, (115270 inhabitants) to determine the prevalence of hereditary ataxias (HA) and hereditary spastic paraplegias (HSP), and the degree of disability they cause.

METHODS

we identified all patients with suspected HA or HSP referred from 1981 to 1991 to in- and out-patient departments, EEG, EMG, and CT-scan services, and centres for the handicapped. Harding's criteria were followed for diagnosis and classification.

RESULTS

at the prevalence day, 17 patients were alive, with a prevalence ratio of 14.8/100,000 population. There were 2 cases of Friedreich's ataxia (FA), 1 of early onset cerebellar ataxia with retained tendon reflexes (EOCA), 1 of autosomal dominant cerebellar ataxia (ADCA), 8 of sporadic idiopathic late onset cerebellar ataxias, and 5 of HSP.

CONCLUSIONS

epidemiological studies on HA and HSP show highly variable prevalence ratios, which could be due in part to the inclusion of sporadic cases. FA, EOCA and ADCA have similar prevalence ratios in most studies.

Epidemiology of primary intracranial tumors in the Valle d'Aosta (Italy) during the 6-year period 1986-1991

A total of 285 new cases of primary intracranial tumors (PIT: 178 cases, 62%) and secondary forms (107 cases, 38%) were detected by CT scan and MRI during a population-based study of the incidence rates of these neoplasms in the Aosta Valley (N.W. Italy: 114,325 residents in 1988) during the period 1986-1991. The PIT are discussed in this paper. Histological confirmation was obtained in 60%. Age- and sex-adjusted mean annual incidence rate for all PIT was 28.3/100,000 (men 21.7; women 28.1). The incidence rates by types were 9.7 for meningiomas (men 5.3; women 13.9), 9.1 for tumors of the neuroepithelial group (men 10; women 8.1), 3.7 for adenomas (men 2.6; women 4.6), and 1.9 for neurinomas (men 2.9; women 0.9). Incidence rate increased with age. Meningiomas comprised 37% of the PIT, followed by tumors of the neuroepithelial group (35%), adenomas (14%, neurinomas (7.3%) and malignant lymphomas (2.3%). The remaining subtypes were 4.6%. Our data showed a clearly higher incidence rate than in previous population-based surveys. The differences were most marked in the meningioma group. The extensive use of CT scan and the more intensive case-finding could explain the differences.

[Telethermographic effects and a comparative clinical assessment of the treatment of shoulder periarthritis using ultrasound]

The aim of this study was the instrumental evaluation of ultrasound therapy in patients with periarthritis of the shoulder, with regard to studies that show doubts about the real effectiveness of the antiinflammatory action of ultrasound. Two groups of subjects were studied, periarthritis versus normal patients. Clinical evaluation and instrumental measures (telethermography) were performed before and after ultrasound therapy. These data were statistically analyzed and constant variations were found, according to clinical evaluation of the patients. Therefore results of this study demonstrated a real influence of ultrasound therapy on periarthritis of the shoulder.

Incidence and prognosis of stroke in the Valle d'Aosta, Italy. First-year results of a community-based study

BACKGROUND AND PURPOSE

We sought to determine the incidence rate, risk factors, and prognosis of stroke in Valle d'Aosta, Italy, to provide information for planning regional health-care facilities.

METHODS

We undertook a prospective study of all new cases of stroke in the geographically defined population of 114,325 residents of Valle d'Aosta in northern Italy.

RESULTS

In the first year of the study (January 1-December 31, 1989), 254 cases of first stroke were registered. The crude annual incidence rate was 2.23/1,000, 1.98/1,000 for men and 2.46/1,000 for women. After adjustment to the 1988 Italian population, the incidence rate for first stroke was 2.15/1,000 per year, 2.48/1,000 per year for men and 1.99/1,000 per year for women. The pathological diagnosis was cerebral infarction in 67%, intracranial hemorrhage in 15%, and unknown in 18%. The overall 30-day case-fatality rate was 31%. In survivors, Barthel Index Score recorded at 30 days from stroke onset showed that 100 patients (62%) were dependent in activities of daily living.

CONCLUSIONS

Our results do not differ significantly from those reported in Umbria, the only similar study performed in Italy, and support non-Italian data as to risk factors in stroke.