Patients with complex regional pain syndrome overestimate applied force in observed hand actions.

BACKGROUND: Movement accuracy is ensured by interaction between motor, somatosensory, and visual systems. In complex regional pain syndrome (CRPS), this interaction is disturbed. To explore CRPS patients' visual perception of actions, we investigated how these patients evaluate the applied force in observed hand actions of another person. METHODS: Nineteen patients suffering from unilateral upper-limb CRPS and 19 healthy control subjects viewed six different videos of left- and right-hand actions. They were asked to evaluate the applied force in each hand action, as well as their subjective sensations of unpleasantness and pain during the observation. RESULTS: The patients overestimated the force applied in the videos: the ratings were two times as large as in the control subjects for actions performed with the hand corresponding to the patients' affected hand, and 1.5 times as large for actions corresponding to their healthy hand. The control subjects considered the stimuli neutral and painless, whereas the patients rated them unpleasant. Moreover, the patients felt increased pain during viewing actions performed with the hand corresponding to their affected side. The overestimation of force was related to the elicited unpleasantness and pain, but not to the patients' muscle strength. CONCLUSIONS: We propose that the overestimation of force is explained both by the pain elicited by the observation and by the abnormal sensorimotor integration that is associated with perception of increased effort. This visually elicited unpleasantness and painfulness may promote avoidance of viewing own actions, further impairing the patients' motor performance.

Estimating viral titres in solutions with low viral loads.

An important consideration in the manufacture of products derived from animal or human sources is the virus reduction capacity of the manufacturing process as estimated using validated bench-scale models of relevant manufacturing steps. In these studies, manufacturing process intermediates are spiked with virus and processed using the bench-scale model and the resulting viral titres of input and output samples are typically determined using cell-based infectivity assays. In these assays, the Spearman-Kärber (SK) method is commonly used to estimate titres when there is one or more positive observation (i.e., the presence of any viral cytopathic effect). The SK method is most accurate when the proportion of positive observations ranges from <0.1 to >0.9 across dilutions but can be biased otherwise. Maximum likelihood (ML) based on a single-hit Poisson model is an alternative widely used estimation method. We compared SK with ML and found the methods to have similar properties except for situations in which the concentration of virus is low but measurable. In this case, the SK method produces upwardly biased estimates of titres. Based on our results, we recommend the use of either ML or SK at most virus concentrations; however, at low virus concentrations ML is preferred.

Virus inactivation and protein recovery in a novel ultraviolet-C reactor.

BACKGROUND AND OBJECTIVES: Ultraviolet-C (UVC) irradiation is a viral-inactivation method that was dismissed by many plasma fractionators as a result of the potential for protein damage and the difficulty in delivering uniform doses. A reactor with novel spiral flow hydraulic mixing was recently designed for uniform and controlled UVC treatment. The objective of this study was to investigate virus inactivation and protein recovery after treatment through the new reactor. MATERIALS AND METHODS: Virus- and mock-spiked Alpha1-proteinase inhibitor (Alpha1-PI) solutions were treated with UVC. The virus samples were assayed for residual infectivity and amplified by the polymerase chain reaction (PCR). The mock-spiked samples were assayed for protein integrity. RESULTS: Greater than 4 log10 of all test viruses were inactivated, regardless of the type of nucleic acid or presence of an envelope. Unlike previous studies, viruses with the smallest genomes were found to be those most sensitive to UVC irradiation, and detection of PCR amplicons > or = 2.0 kb was correlated to viral infectivity. Doses that achieved significant virus inactivation yielded recovery of > 90% protein activity, even in the absence of quenchers. CONCLUSIONS: The results demonstrate the effectiveness of UVC treatment, in the novel reactor, to inactivate viruses without causing significant protein damage, and confirm the utility of large PCR amplicons as markers for infectious virus.

Association of apolipoprotein E polymorphism in late-onset Alzheimer's disease and vascular dementia in Brazilians.

The genetic basis for dementias is complex. A common polymorphism in the apolipoprotein E (APOE) gene is considered to be the major risk factor in families with sporadic and late-onset Alzheimer's disease as well as in the general population. The distribution of alleles and genotypes of the APOE gene in late-onset Alzheimer's disease (N = 68), other late-life dementias (N = 39), and in cognitively normal controls (N = 58) was determined, as also was the risk for Alzheimer's disease associated with the epsilon4 allele. Peripheral blood samples were obtained from a total of 165 individuals living in Brazil aged 65-82 years. Genomic DNA was amplified by the polymerase chain reaction and the products were digested with HhaI restriction enzyme. APOE epsilon2 frequency was considerably lower in the Alzheimer's disease group (1%), and the epsilon3 allele and epsilon3/epsilon3 genotype frequencies were higher in the controls (84 and 72%, respectively) as were the epsilon4 allele and epsilon3/epsilon4 genotype frequencies in Alzheimer's disease (25 and 41%, respectively). The higher frequency of the epsilon4 allele in Alzheimer's disease confirmed its role as a risk factor, while epsilon2 provided a weak protection against development of the disease. However, in view of the unexpectedly low frequency of the epsilon4 allele, additional analyses in a more varied Brazilian sample are needed to clarify the real contribution of apolipoprotein E to the development of Alzheimer's disease in this population.

Association of apolipoprotein E polymorphism in late-onset Alzheimer's disease and vascular dementia in Brazilians

The genetic basis for dementias is complex. A common polymorphism in the apolipoprotein E (APOE) gene is considered to be the major risk factor in families with sporadic and late-onset Alzheimer's disease as well as in the general population. The distribution of alleles and genotypes of the APOE gene in late-onset Alzheimer's disease (N = 68), other late-life dementias (N = 39), and in cognitively normal controls (N = 58) was determined, as also was the risk for Alzheimer's disease associated with the epsilon4 allele. Peripheral blood samples were obtained from a total of 165 individuals living in Brazil aged 65-82 years. Genomic DNA was amplified by the polymerase chain reaction and the products were digested with HhaI restriction enzyme. APOE epsilon2 frequency was considerably lower in the Alzheimer's disease group (1 percent), and the epsilon3 allele and epsilon3/epsilon3 genotype frequencies were higher in the controls (84 and 72 percent, respectively) as were the epsilon4 allele and epsilon3/epsilon4 genotype frequencies in Alzheimer's disease (25 and 41 percent, respectively). The higher frequency of the epsilon4 allele in Alzheimer's disease confirmed its role as a risk factor, while epsilon2 provided a weak protection against development of the disease. However, in view of the unexpectedly low frequency of the epsilon4 allele, additional analyses in a more varied Brazilian sample are needed to clarify the real contribution of apolipoprotein E to the development of Alzheimer's disease in this population

Evaluation of virus and prion reduction in a new intravenous immunoglobulin manufacturing process.

BACKGROUND AND OBJECTIVES: Minimizing the transmission risk of infectious diseases is of primary importance in the manufacture of products derived from human plasma. A novel chromatography-based intravenous immunoglobulin (IGIV) manufacturing process was developed and the reduction of virus and transmissible spongiform encephalopathies (TSE) during the manufacturing process was assessed. Mechanistically distinct steps that could affect virus reduction were identified, and the robustness of virus reduction over the range of process conditions was determined. MATERIALS AND METHODS: Virus and TSE reduction by processing steps were assessed using a scaled-down version of the IGIV manufacturing process. RESULTS: Virus and TSE reduction at manufacturing process set points were well within safety standards. Robustness studies verified that the reproducibility of virus reduction was maintained at or beyond operating parameter extremes. Virus reduction across two combined manufacturing steps was lower than the sum of virus-reduction values across the individual steps, indicating mechanistic similarity of the two steps with respect to virus reduction. Only reduction from mechanistically distinct steps was claimed. CONCLUSIONS: This comprehensive approach to pathogen safety provides the new immunoglobulin manufacturing process with a detailed, yet realistic, assessment of the risk of transmission of infectious pathogens.

The X-X-/E+E+ genotype of the XbaI/EcoRI polymorphisms of the apolipoprotein B gene as a marker of coronary artery disease in a Brazilian sample.

Studies that consider polymorphisms within the apolipoprotein B (apo B) gene as risk factors for coronary artery disease (CAD) have reported conflicting results. The aim of the present study was to search for associations between two DNA RFLPs (XbaI and EcoRI) of the apo B gene and CAD diagnosed by angiography. In the present study we compared 116 Brazilian patients (92 men) with CAD (CAD+) to 78 control patients (26 men) without ischemia or arterial damage (CAD-). The allele frequencies at the XbaI (X) and EcoRI (E) sites did not differ between groups. The genotype distributions of CAD+ and CAD- patients were different (chi (1) = 6.27, P = 0.012) when assigned to two classes (X-X-/E+E+ and the remaining XbaI/EcoRI genotypes). Multivariate logistic regression analysis showed that individuals with the X-X-/E+E+ genotype presented a 6.1 higher chance of developing CAD than individuals with the other XbaI/EcoRI genotypes, independently of the other risk factors considered (sex, tobacco consumption, total cholesterol, hypertension, and triglycerides). We conclude that the X-X-/E+E genotype may be in linkage disequilibrium with an unknown variation in the apo B gene or with a variation in another gene that affects the risk of CAD.

The X-X-/E+E+ genotype of the XbaI/EcoRI polymorphisms of the apolipoprotein B gene as a marker of coronary artery disease in a Brazilian sample

Studies that consider polymorphisms within the apolipoprotein B (apo B) gene as risk factors for coronary artery disease (CAD) have reported conflicting results. The aim of the present study was to search for associations between two DNA RFLPs (XbaI and EcoRI) of the apo B gene and CAD diagnosed by angiography. In the present study we compared 116 Brazilian patients (92 men) with CAD (CAD+) to 78 control patients (26 men) without ischemia or arterial damage (CAD-). The allele frequencies at the XbaI (X) and EcoRI (E) sites did not differ between groups. The genotype distributions of CAD+ and CAD- patients were different (chi²(1) = 6.27, P = 0.012) when assigned to two classes (X-X-/E+E+ and the remaining XbaI/EcoRI genotypes). Multivariate logistic regression analysis showed that individuals with the X-X-/E+E+ genotype presented a 6.1 higher chance of developing CAD than individuals with the other XbaI/EcoRI genotypes, independently of the other risk factors considered (sex, tobacco consumption, total cholesterol, hypertension, and triglycerides). We conclude that the X-X-/E+E genotype may be in linkage disequilibrium with an unknown variation in the apo B gene or with a variation in another gene that affects the risk of CAD

Enveloped virus inactivation by caprylate: a robust alternative to solvent-detergent treatment in plasma derived intermediates.

Solvent-detergent treatment, although used routinely in plasma product processing to inactivate enveloped viruses, substantially reduces product yield from the human plasma resource. To improve yields in plasma product manufacturing, a new viral reduction process has been developed using the fatty acid caprylate. As licensure of plasma products warrants thorough evaluation of pathogen reduction capabilities, the present study examined susceptibility of enveloped viruses to inactivation by caprylate in protein solutions with varied pH and temperature. In the immunoglobin-rich solutions from Cohn Fraction II+III, human immunodeficiency virus, Type-1, bovine viral diarrhea virus (BVDV), and pseudorabies virus were inactivated by caprylate concentrations of >/=9 mM, >/=12 mM, and >/=9 mM, respectively. Compared to solvent-detergent treatment, BVDV inactivation in Fraction II+III solution was significantly faster (20-60 fold) using 16 mM caprylate. Caprylate-mediated inactivation of BVDV was not noticeably affected by temperature within the range chosen manufacturing the immunoglobulin product. In Fraction II+III solutions, IgG solubility was unaffected by

Evidence for dissociation of spatial and nonspatial auditory information processing.

Several lines of evidence suggest that visual information processing is segregated into the ventral "what" and dorsal "where" pathways. But the question whether information processing in the auditory system is also parceled to spatial and nonspatial domains remains open. In the present study, we performed simultaneous EEG and MEG recordings during auditory location and pitch delayed matching-to-sample tasks to find out whether working memory processing of the auditory stimulus attribute affects the transient components of the evoked potentials. In both tasks, identical blocks of tone stimuli of one of two frequencies were presented in one of two locations; the only difference between the tasks was the instruction to attend either to the frequency or to the location. In the match condition, the N1 latency was shorter and the N1m amplitude larger in the location task compared to the pitch task. Furthermore, the right-hemisphere generator of N1m elicited in the match condition of the location task was situated significantly medially to the N1m generator in the match condition of the pitch task. Latency and amplitude task-related differences in the N1/N1m components as well as the source location differences indicate at least partial segregation of neuronal mechanisms involved in working memory processing of spatial and nonspatial auditory information.

Pathological features of the lung in fatal high altitude pulmonary edema occurring at moderate altitude in Japan.

In order to characterize the pathological features of high altitude pulmonary edema (HAPE) occurring at moderate altitude in Japan, we performed routine hematoxylin and eosin (HE) staining in lung materials from HAPE autopsied cases. We also undertook advanced immunohistochemical staining for observation of type II pneumocytes, pulmonary surfactant (PS), and mast cells in the lung of HAPE cases to examine the biological changes within the lung parenchyma. The pathological findings of HAPE were characterized by alveolar edema, congestion of pulmonary vessels, alveolar hyaline membranes, alveolar hemorrhage, and multithrombi and fibrin clots, but maintained alveolar structure. The immunostaining results showed that the type II pneumocytes were cellular fusion, deformity, and exfoliation from the walls of alveoli; the PS not only lined the alveolar surface, but was also patchily distributed within alveoli; and the number of mast cells were increased (9.0 +/- 0.9 cells/mm(2)) compared to that in controls (1.1 +/- 0.4 cells/mm(2)) (p < 0.01). We conclude that the pathological features of HAPE at moderate altitude in Japan are similar to others reported worldwide, and that the type II pneumocytes, PS, and mast cells may contribute to some extent to pathophysiological parts in the development and progression of HAPE.

Concurrent left-sided spontaneous pneumothorax in Japanese monogerminal twins.

Monogerminal twin brothers aged 17 were admitted because of concurrent left-sided spontaneous pneumothorax. A familial background of this common disease in association with the human leukocyte antigen (HLA) has been suggested; however, the actual mode of inheritance in association with HLA typing is still uncertain. HLA analysis in this family revealed the HLA-A24, B61 (40), Cw3, DR4, DR53, and DQ3 haplotype in the twins and their father, who also had a medical history of spontaneous pneumothorax. We report these cases as an extremely rare example of familial occurrence of spontaneous pneumothorax.

[A case of renal cell carcinoma complicated with interstitial pneumonitis, complete A-V block and pleural effusion during interferon-alpha therapy].

A 76-year-old man with postoperative renal cell carcinoma accompanied by multiple lung metastasis was being treated with recombinant interferon-alpha. After administration of 3 MU/day on 3 days/week for 1 month, he complained of headache and tinnitus. During continuous treatment for 3 months, he complained of appetite loss, low-grade fever and dyspnea. He was then referred to our Department of Internal Medicine. Electrocardiography indicated a complete A-V block, and chest radiography (CXR) showed a reticular shadow in both lower lung fields and bilateral pleural effusion. Chest computed tomography (CT) indicated subpleural emphysematous changes, multiple nodules, consolidation shadow with ground glass opacity in both lower lobes, and bilateral pleural effusion. The findings in the bronchoalveolar lavage (BAL) fluid included increases in the numbers of lymphocytes and eosinophils. We reached a diagnosis of interferon-alpha-induced pneumonitis on the basis of the patient's clinical course, and the CXR, chest CT and BAL fluid findings. Treatment with methylprednisolone pulse therapy for 3 days and then administration of prednisolone for 1 month resulted in marked improvement in the complete A-V block and interstitial pneumonitis. At day 7 after discontinuation of prednisolone, the serum level of C-reactive protein increased, and CXR showed bilateral pleural effusion. We therefore believe that the pleural effusion was probably also induced by interferon-alpha. Interferon is an effective drug for chronic hepatitis C and malignant diseases. Many complications have been reported during interferon therapy. However, although these complications, such as interstitial pneumonitis, complete A-V block and pleural effusion, have rarely been reported, careful attention is required during interferon therapy in case any appear.

[A case of intrathoracic schwannoma derived from the left vagus nerve].

We report a case of schwannoma asymptomatic for 9 years, derived from the left vagus nerve in the middle mediastinum. This spindle-shaped tumor caused paralysis of the left recurrent nerve as an initial clinical manifestation with cough. T2-weighted magnetic resonance imaging (MRI) showed a neurogenic tumor with a characteristic target appearance and with constituents of different intensities: mucinous material in the peripheral zone and solitary tissue in the central zone. But, this different intensity is not directly reflected by the histopathologic features of Antoni types A and B. These findings suggest that MRI is useful for determining the parent nerve of a neurogenic tumor and is helpful for the diagnosis.

Analysis of radiation pressure exerted on a metallic particle within an evanescent field.

Radiation pressure induced by an evanescent field was experimentally analyzed for a single submicrometer-sized gold particle. The force measurement was based on a thermodynamic analysis of Brownian motion by use of a three-dimensional position-sensing technique. The lateral radiation pressure could be ascribed to a scattering force, which was oriented in the same direction as the propagation vector of the incident laser beam. The potential profile in the longitudinal direction indicated that the gold particle was attracted to the high-intensity region of the evanescent field by a gradient force.

Plasma fatty acids in children with grade III protein-energy malnutrition in its different clinical forms: marasmus, marasmic kwashiorkor, and kwashiorkor.

Plasma fatty acid patterns were analysed in 15 children aged 2 to 42 months (median = 12 months) admitted to the University Hospital, Faculty of Medicine of Ribeirão Preto, University of São Paulo, suffering from grade III protein-energy malnutrition in its different clinical forms: marasmus (n = 5), marasmic kwashiorkor (n = 5), and kwashiorkor (n = 5). A control group of eight children from the same population aged 3 to 22 months (median = 12 months) was also studied. Plasma fatty acids were analysed by gas liquid chromatography. The plasma fatty acid patterns detected in grade III protein-energy malnutrition indicated changes characteristic of essential fatty acid deficiency, with lower linoleic acid (C18:2) levels in the three groups (p < 0.05). The major metabolite of linoleic acid, arachidonic acid (C20:4), was lower in the kwashiorkor group than in the control group (p < 0.05). Linoleic acid (C18:2) levels were lower in the marasmus group than in the kwashiorkor group (p < 0.05). Several factors may have contributed to these changes, such as a decreased content of linoleic acid in the diet, plus malabsorption and/or poor utilization of fats, and changes in the synthesis or degradation of these fatty acids. Although many questions remain unanswered, we suggest that an adequate amount of linoleic acid be added to the rehabilitation diet of these children in the form of vegetable fat.

Determination of adequate moisture content for efficient dry-heat viral inactivation in lyophilized factor VIII by loss on drying and by near infrared spectroscopy.

A requirement for a minimal threshold level of moisture in order for efficient virus inactivation to occur during dry heat treatment of freeze-dried coagulation factor concentrates is described. Techniques used to determine moisture content during heating were Loss on Drying and Karl Fischer. The Loss on Drying was suspected to have occasional errors as a result of sample preparation being influenced by interference from atmospheric moisture. Therefore, a non-invasive, non-destructive method for determination of residual moisture content using near infrared spectrometry (NIR) was developed for freeze-dried antihaemophilic factor (AHF). Calibration equations were determined against Loss on Drying and Karl Fischer assay methods and these equations evaluated for the predictive efficiency. Both Loss on Drying and NIR were used to evaluate the effect of moisture content on the efficiency of virus inactivation by dry heat at 80 degrees C. A minimum level of moisture of greater than 0.7%, as determined by Loss on Drying, was necessary for a virus reduction in the magnitude of 4 log10 for hepatitis A virus, porcine parvovirus and pseudorabies virus.

[Cerebellopontine angle epithelial cyst presenting as hemifacial spasm].

A rare case of cerebellopontine angle epithelial cyst presenting as hemifacial spasm is reported. The patient was a 35-year-old man with right hemifacial spasm of 2 months duration. A preoperative CT scan showed a well-demarcated low density area in the right cerebellopontine angle. The cyst was totally excised under an operating microscope. The postoperative course was uneventful, and the right hemifacial spasm resolved immediately. Histologically, the cyst wall was composed of a stratified epithelial lining composed of non-ciliated cuboidal or squamous cells. Ultrastructurally, the epithelial layer consisted of two types of cells: non-ciliated cells with microvilli coated with electron-dense material, and basally located cells with tonofilaments and well-developed desmosomes. The latter type of cells appear identical to the basal cells characteristically seen in the upper respiratory tract and the gastrointestinal tract. This findings suggest that the cyst was of endodermal origin rather than neuroectodermal origin.

[Anterior choroidal artery territory infarction with transcortical sensory aphasia after a neck clipping of left internal carotid artery aneurysms: a case report].

Anterior choroidal artery (Ach A) syndrome is widely known to be composed of a triad of hemiparesis, hemisensory loss and homonymous hemianopia. The authors report a case of Ach A-territory infarction after a direct operation for internal carotid artery aneurysms, which presented transcortical sensory aphasia in association with the characteristic triad. The literature and several previously reported cases with dominant and nondominant cerebral hemisphere signs in AcH A infarction are reviewed. The danger of Ach A occlusion and the importance of preserving it during aneurysm surgery are emphasized.

In situ measurements of ion-exchange processes in single polymer particles: laser trapping microspectroscopy and confocal fluorescence microspectroscopy.

Ion-exchange processes of a cationic dye (Rhodamine B; RhB) were studied for individual polymer particles (diameter of 16-20 µm) by laser trapping microspectroscopy and confocal fluorescence laser microspectroscopy. The absorbance of RhB at 565 nm adsorbed on a cation-exchange particle increased linearly with the concentration of RhB in the aqueous phase, while it was independent of the particle diameter. Fluorescence intensity profile measurements of RhB along the particle diameter by confocal fluorescence microspectroscopy directly proved that ion exchange took place in the surface layer (∼2-µm thickness) of the particle in the initial stage (1 h). Diffusion of RhB in the particle was very slow, and ion exchange proceeded gradually to the inner volume in the order of days. The ion-exchange processes were analyzed on the basis of simulation of the time course of the concentration profile of RhB in the particle, and the diffusion coefficient of RhB was determined to be (2-4) × 10(-11) cm(2)·s(-1).