Allergic sensitization to laboratory animals is more associated with asthma, rhinitis, and skin symptoms than sensitization to common allergens.

BACKGROUND: Workers exposed to laboratory animals have a high risk of developing laboratory animal allergy (LAA). Atopy seems to be the main risk factor for LAA. We hypothesized that occupational sensitization is a better predictor for the development of asthma, rhinitis, and bronchial hyperresponsiveness (BHR) than common sensitization. OBJECTIVE: To investigate the association between occupational sensitization to laboratory animals and clinical outcomes. METHODS: This was a cross-sectional study performed at two universities on students and employees dealing with small rodents. The subjects were allocated in groups: non-sensitized, common sensitization, or occupational sensitization, according to the results of the skin prick test (SPT). All subjects answered a questionnaire about animal exposures, symptoms, allergic diseases, and underwent spirometry and bronchial challenge test with mannitol. Multivariate analysis was performed using Poisson regression to estimate the prevalence ratio (PR). RESULTS: Data from 453 volunteers were analysed. Non-sensitized group comprised 237 subjects; common sensitization group, 142 subjects; and occupational sensitization group, 74 subjects. Occupational sensitization was associated with greater risk for all outcomes studied. When the common sensitization group was reference, skin symptoms had PR of 1.36, 95% confidence interval (CI): 1.01-1.85; wheezing had PR of 1.75, CI 95%: 1.21-2.53; rhinitis had PR of 1.25, 95%: 1.11-1.40; nocturnal dyspnoea had PR of 2.40, 95% CI: 1.31-4.40; bronchial hyperresponsiveness (BHR) had PR of 2.47, 95% CI: 1.50-4.09; and confirmed asthma had PR of 2.65, 95% CI: 1.45-4.85. In addition, the overlap of asthma, rhinitis, and skin symptoms in a same subject was significantly more prevalent in the occupational sensitization group, 16.2% versus 4.9% in the common sensitization group. CONCLUSION AND CLINICAL RELEVANCE: Occupational sensitization is associated with allergic symptoms and respiratory diseases. SPT with occupational allergens along with other parameters may contribute to detection of risk for allergic and respiratory diseases associated with exposure to laboratory animals.

3D evaluation of maxillary arches in unilateral cleft lip and palate patients treated with nasoalveolar moulding vs. Hotz's plate.

To compare the three-dimensional changes occurring in the maxillary arch during the use of modified pre-surgical nasoalveolar moulding (PNAM) and Hotz's plate. A clinical trial including 32 children with unilateral cleft lip and palate (UCLP), 16 treated with Hotz's plate and 16 with PNAM, was performed. Impressions of the maxillary arches were taken: A. prior to pre-surgical orthopaedics, B. before cheiloplasty and C. after cheiloplasty. Models were digitised using a stereophotogrammetric instrument, and geodesic distances were calculated: anterior, canine and posterior widths of the arch, and lengths and cleft depths of the larger and shorter segments. The time and treatment effects were assessed by two-factor anova. A significant effect of treatment was found for cleft depth at the larger segment: children treated with Hotz's plate had significantly deeper cleft than children treated with PNAM. All distances significantly changed during time: the anterior and canine widths decreased, while the posterior width, the lengths and depths of the cleft segments increased. Significant treatment per time interactions was found. The anterior and canine widths reduced more with PNAM between time points A and B while Hotz's treatment was more effective between B and C. The shorter segment depth increased more between B and C with PNAM, and between A and B with Hotz's plate. During pre-surgical orthopaedics, therapy with PNAM obtained the best results in reducing the width at the anterior segment of the cleft. This treatment gave a lower increase in cleft depth than treatment with Hotz's plate.

Application of a computational model of vagus nerve stimulation.

OBJECTIVES: The most widely used and studied neurostimulation procedure for medically refractory epilepsy is vagus nerve stimulation (VNS) Therapy. The goal of this study was to develop a computational model for improved understanding of the anatomy and neurophysiology of the vagus nerve as it pertains to the principles of electrical stimulation, aiming to provide clinicians with a systematic and rational understanding of VNS Therapy. MATERIALS AND METHODS: Computational modeling allows the study of electrical stimulation of peripheral nerves. We used finite element electric field models of the vagus nerve with VNS Therapy electrodes to calculate the voltage field for several output currents and studied the effects of two programmable parameters (output current and pulse width) on optimal fiber activation. RESULTS: The mathematical models correlated well with strength-duration curves constructed from actual patient data. In addition, digital constructs of chronic versus acute implant models demonstrated that at a given pulse width and current combination, presence of a 110-µm fibrotic tissue can decrease fiber activation by 50%. Based on our findings, a range of output current settings between 0.75 and 1.75 mA with pulse width settings of 250 or 500 µs may result in optimal stimulation. CONCLUSIONS: The modeling illustrates how to achieve full or nearly full activation of the myelinated fibers of the vagus nerve through output current and pulse width settings. This knowledge will enable clinicians to apply these principles for optimal vagus nerve activation and proceed to adjust duty cycle and frequency to achieve effectiveness.

EMG analysis of trapezius and masticatory muscles: experimental protocol and data reproducibility.

We aimed to define a standardised protocol for the electromyographic evaluation of trapezius muscle in dentistry and to assess its within- and between-session repeatability. Surface electromyography of trapezius, masseter and temporal muscles was performed in 40 healthy subjects aged 20-35 years during shoulder elevation, and maximum teeth clenching with and without cotton rolls. Two repetitions were made both within (same electrodes) and between sessions (different electrodes). Maximum voluntary clench on cotton rolls was used to standardise the potentials of the six analysed muscles with tooth contact; shoulder elevation was used to standardise the upper trapezius potentials. From the standardised electromyographic potentials, several indices (muscle symmetry; masticatory muscle torque and relative activity; total masticatory muscle activity; trapezius cervical load, percentage co-contraction of trapezius during teeth clenching) were computed; random (technical error of measurement) and systematic (Student's t-test, Analysis of Variance) errors were assessed. For all indices, no systematic errors were found between the two separate data collection sessions. Within session, limited (lower than 8%) technical errors of measurement were found for temporalis and masseter symmetry, torque and activity indices, and the trapezius cervical load. Larger random errors were obtained for trapezius symmetry and total masticatory muscle activity (up to 20%). Between sessions, no significant differences were found for trapezius co-contraction. In conclusion, a protocol for the standardisation of trapezius muscle that may be used within dental clinical applications was defined, and the repeatability of masseter, temporalis and trapezius electromyographic recordings for serial assessments was assessed in healthy subjects.

Immediate effect of an elastomeric oral appliance on the neuromuscular coordination of masticatory muscles: a pilot study in healthy subjects.

To compare the electromyographic characteristics of masticatory muscles with and without a new elastomeric oral device proposed for masticatory muscle training, 10 healthy subjects aged 23 to 32 were examined. Surface electromyography of masseter and temporal muscles was performed during maximum teeth clenching without and with the device and during unilateral chewing with either gum or the device. During clenching, a significant increment of the overall muscular activity was promoted by the occlusal device in comparison with the intercuspal teeth clenching (P=0·05). Muscular standardised activity during device chewing was significantly higher than that during gum chewing (P=0·005), and it was more evenly distributed between working and balancing sides (P=0·023 right side, P=0·039 left side), and between masseter and temporal muscles (right side test, P=0·014). No significant differences were found for the global neuromuscular co-ordination, the masticatory symmetry and the chewing frequency. Clenching and chewing with the analysed occlusal prostheses was performed with a relative increment of muscular activity. These findings may be the basis for the training effect proposed for this device.

Nasal base symmetry: a three dimensional anthropometric study.

AIM: The aim of this paper was to evaluate directional and fluctuating asymmetry, nostril and alar divergence in the nasal base of healthy young adults. To estimate nostril area and to investigate its relationships with cutaneous nasal area. METHODS: Three-dimensional plaster models of the nose of 20 young healthy white adults were obtained, digitized and mathematically reconstructed using Non Uniform Rational B-Splines (NURBS) curves. Linear distances (alar length, nostril axis length), angles (interalar angle, interaxial angle; angle between each nostril and alar axes), and surface areas (cutaneous nasal surface; right and left nostril area) were computed using NURBS-reconstructed models. RESULTS: The left side nasal structures were somewhat larger than the homologous right side ones (P<0.05). Nostril axis was approximately 60% of the corresponding alar length. Nostril area was approximately 3% of cutaneous nasal area. Alar length explained 31-36% of the individual variations in nostril axis length. Cutaneous nasal area explained 54-56% of nostril area, while the interalar angle explained 35% of the variations in interaxial angle. CONCLUSIONS: The method provided simple measurements of nasal base dimensions and asymmetry; some asymmetry was found also in healthy adults; only moderate relationships between nostril and alar dimensions and angles, as well as between nasal and nostril areas, were found, thus pointing to the necessity of detailed nostril assessments.

SUMCOR: Cascade summing correction for volumetric sources applying MCNP6.

The main features of code SUMCOR developed for cascade summing correction for volumetric sources are described. MCNP6 is used to track histories starting from individual points inside the volumetric source, for each set of cascade transitions from the radionuclide. Total and FEP efficiencies are calculated for all gamma-rays and X-rays involved in the cascade. Cascade summing correction is based on the matrix formalism developed by Semkow et al. (1990). Results are presented applying the experimental data sent to the participants of two intercomparisons organized by the ICRM-GSWG and coordinated by Dr. Marie-Cristine Lépy from the Laboratoire National Henri Becquerel (LNE-LNHB), CEA, in 2008 and 2010, respectively and compared to the other participants in the intercomparisons.

Detecting and modelling delayed density-dependence in abundance time series of a small mammal (Didelphis aurita).

We study the population size time series of a Neotropical small mammal with the intent of detecting and modelling population regulation processes generated by density-dependent factors and their possible delayed effects. The application of analysis tools based on principles of statistical generality are nowadays a common practice for describing these phenomena, but, in general, they are more capable of generating clear diagnosis rather than granting valuable modelling. For this reason, in our approach, we detect the principal temporal structures on the bases of different correlation measures, and from these results we build an ad-hoc minimalist autoregressive model that incorporates the main drivers of the dynamics. Surprisingly our model is capable of reproducing very well the time patterns of the empirical series and, for the first time, clearly outlines the importance of the time of attaining sexual maturity as a central temporal scale for the dynamics of this species. In fact, an important advantage of this analysis scheme is that all the model parameters are directly biologically interpretable and potentially measurable, allowing a consistency check between model outputs and independent measurements.

Metabolic and endocrine aspects of the ketogenic diet.

The ketogenic diet (KD) is designed to simulate the biochemical effects of fasting by maintaining a state of ketosis. The complex interplay of endocrine and metabolic factors requires that a continuous ingestion of a diet high in lipid calories is necessary to achieve such a state and yet maintain body weight. The resulting condition provides for much of the cerebral energy requirements in the form of ketone bodies. We review energy metabolism with special emphasis on fatty acid oxidation to provide the readers with a foundation that facilitates identification of patients who will especially benefit from this diet, as well as to assist clinicians in screening candidates who may experience a catastrophic outcome if fasted and placed on this diet. The review includes a discussion of the role of carnitine in mitochondrial fatty acid metabolism, and the criteria for carnitine supplementation. Only limited information is available regarding the interaction of the diet with the commonly used antiepileptic drugs.

Moyamoya syndrome in a patient with congenital human immunodeficiency virus infection.

A 10-year-old boy with congenital human immunodeficiency virus (HIV) infection developed recurrent episodes of left hemiparesis at age 7 years. The progression of his disease was followed by computed tomography, magnetic resonance imaging, magnetic resonance angiography, and cerebral angiography. The series of images showed progressive stenosis of both carotid arteries at the suprasellar origin with involvement of his anterior and middle cerebral arteries, while prominent collateral vessels developed from his external carotid supply through ophthalmic and middle meningeal arteries. The pattern of cerebrovascular disease is consistent with moyamoya syndrome. We suggest that further studies on the pathophysiology of cerebrovascular disease in patients with HIV could be helpful in understanding the cause of moyamoya disease as well. Also, with the various advances in treatment of HIV, neurovascular complications could be seen more frequently as the long-term survival in these patients improves.

Temporal lobectomy in early childhood: the need for long-term follow-up.

We retrospectively identified 15 children ages 12 years and under with anticonvulsant resistant epilepsy who underwent a temporal lobectomy at Children's Hospital, Boston, between 1978 and 1993. Our aim was to study the long-term seizure outcome. Data pertaining to preoperative evaluation, electroencephalography (EEG), neuroimaging, surgery, seizure outcome, and postoperative complications were reviewed. Only patients followed for more than 12 months were included. The average duration of follow-up was 57 months. At the last visit, 47% (7 of 15) of the children were seizure free or only had auras: another 33% (5 of 15) had > 90% reduction in seizure frequency. Three patients had < 90% seizure reduction. Four cases were initially seizure free but had subsequent recurrence between 11 and 28 months after the epilepsy surgery. Factors associated with a good outcome include exclusively focal EEG discharges or an imaging suggestive of a low-grade tumor; factors associated with a poor outcome include generalized EEG discharges and a normal magnetic resonance image. Temporal lobectomy is useful in the treatment of early childhood drug-resistant partial epilepsy, but long-term follow-up is necessary as late seizure recurrence may occur up to 28 months after surgery.

Entropy-based analysis of the number partitioning problem.

In this paper we apply the multicanonical method of statistical physics on the number partitioning problem (NPP). This problem is a basic NP-hard problem from computer science, and can be formulated as a spin-glass problem. We compute the spectral degeneracy, which gives us information about the number of solutions for a given cost E and cardinality difference m. We also study an extension of this problem for Q partitions. We show that a fundamental difference on the spectral degeneracy of the generalized (Q>2) NPP exists, which could explain why it is so difficult to find good solutions for this case.

Shortest paths on systems with power-law distributed long-range connections.

We discuss shortest-path lengths l(r) on periodic rings of size L supplemented with an average of pL randomly located long-range links whose lengths are distributed according to P(l) approximately l(-mu). Using rescaling arguments and numerical simulation on systems of up to 10(7) sites, we show that a characteristic length xi exists such that l(r) approximately r for r>xi. For small p we find that the shortest-path length satisfies the scaling relation l(r,mu,p)/xi=f(mu,r/xi). Three regions with different asymptotic behaviors are found, respectively: (a) mu>2 where theta(s)=1, (b) 1

When might hemispheric favouring of epileptiform discharges begin?

PURPOSE: EEG studies based on adult populations report interictal epileptiform discharges (EDS) favour the left hemisphere. It is not clear when favouring becomes apparent as similar paediatric studies have not been performed. METHODS: The authors reviewed 1,579 paediatric EEG interpretations for evidence of hemispheric favouring of focal epileptiform discharges. Analysis focused on first-time EEG results. RESULTS: Right hemispheric favouring of interictal epileptiform discharges occurs in childhood, it remits around 5 years of age whereupon left-sided favouring occurs more frequently (P=0.004, Fisher's Exact). CONCLUSION: Hemispheric vulnerabilities to interictal focal epileptiform activity may display discrete age-related favouring. These findings are discussed in context of normal hemispheric maturation.

Eosinophil levels in the acute phase of experimental Chagas' disease.

Eosinophil dynamics, in bone marrow, blood and peritoneal exudate, of resistant C57B1/6 (C57) and susceptible A/Snell (A/Sn) mice was comparatively studied during the acute phase of infection by Trypanosoma cruzi Y strain. A decline was observed in bone marrow eosinophil levels in A/Sn, but not in C57 mice, soon after infection, those of the former remaining significantly below those of the latter up to the 4th day of infection. Bone marrow eosinophil levels of C57 mice declined subsequently to levels comparable to those of A/Sn mice, the number of these cells in this compartment remaining 50% those of non infected controls, in both strains, up to the end of the experiment on the 14th day of infection. The fluctuations in eosinophil levels in blood and peritoneal space were similar in both mice strains studied. Concomitantly with depletion of eosinophils in the marrow, depletion in blood and a marked rise of these cells in the peritoneal space. initial site of infection, occurred in both strains. The difference in eosinophil bone marrow levels, between C57 and A/Sn mice, observed in the first four days of infection, suggests a higher eosinopoiesis capacity of the former in this period, which might contribute to their higher resistance to T. cruzi infection.

[Pseudotumor cerebri without optic papilledema]. / Pseudotumor cerebral sem edema de papila óptica.

Four cases of benign intracranial hypertension in two nonobese women (23 and 35 yr. old) and two nonobese men (both 47 yr. old) are presented. The most remarkable finding of the clinical investigation of these cases was the absence of papilledema. Our finding is consistent with other reports, and suggest that the presence of papilledema should not be considered critical for the diagnosis of benign intracranial hypertension. Additionally, the authors present a hypothesis for the absence of papilledema in cases otherwise typical of benign intracranial hypertension.

[Benign intrinsic tectal tumors: apropos of 2 cases]. / Tumores intrínsecos benignos da região tectal: considerações a propósito de dois casos.

The introduction of computerized tomography and magnetic resonance imaging led to the knowledge that brain stem tumors are not a homogeneous group with regard to their clinical, pathological and biological features. The classical concept of an uniformly poor prognosis has been modified and some subtypes of tumors are amenable to surgical treatment and long-term survival. The authors report two cases of patients with tumors of the tectal region whose symptoms and CT features were consistent with late-onset aqueductal obstruction. In both cases definitive diagnosis was established by MRI and symptoms resolved after ventriculo-peritoneal shunt implantation. The clinic and pathological features and therapeutical alternatives as well, are discussed.

[Echocardiography in the evaluation of cardiac involvement in seronegative spondylo-arthropathies]. / El ecocardiograma en la evaluación del compromiso cardiáco en las espondiloartropatías seronegativas.

To evaluate the involvement of the heart in patients with seronegative spondyloarthropathies by echodopplercardiography, 35 patients including 20 with ankylosing spondylitis, 10 with Reiter's syndrome and 5 with psoriatic arthritis (21 men and 14 women, with ages ranging from 17-68 years and averaging 38.5) were studied. Most were asymptomatic with respect to the cardiovascular system (65.71%) and 12 oligosymptomatic with palpitations as their main complaint. Each patient had an echocardiogram and electrocardiogram. A two-dimensional echocardiogram demonstrated alterations in 19 patients (54.29%), 28.58% asymptomatic and 25.71% symptomatic. This study revealed most of lesions (17/19-84.47%) followed by the Dopplerechocardiography (10/19-52.63%) and the one-dimensional echocardiography (9/19-47.36%). Abnormal aortic valves were found in 10 patients, in 7 thickenning and in 3 calcifications. The mitral valve was involved in 11 patients, in 8 thickenning, in 1 calcification and in 2 valve prolapse. In ankylosing spondylitis aortic valve disease was found in 8 patients. Dopplerechocardiography evidenced the presence of aortic regurgitation in 4 patients and mitral insufficiency in 3. The Q-T interval was increased in 19 patients, there was one first degree auriculoventricular block, one right branch block and one sinus bradicardia. Thus the echocardiogram is an excellent noninvasive method to disclose cardiac disturbances in patients with seronegative spondyloarthropaties.

[Basic causes of death in elderly patients with Chagas' disease]. / Causas básicas de morte em chagásicos idosos.

The main causes of death of 100 elderly Chagas' patients (group A), of 100 elderly non-Chagas' disease (group B) and of 100 non-elderly Chagas' disease patients (group C) were surveyed clinically and by postmortem data. Compared to B, the A group showed significantly more deaths due to chronic Chagas' heart disease and digestive "megas", and less frequently to malignant neoplasm. Deaths due to pulmonary emphysema and malignant neoplasms were significantly more common and deaths due to chronic Chagas' heart disease were significantly less common in the A group when compared to the C group. Chronic Chagas' heart disease caused 26 unexpected sudden deaths in the C group (the younger patients) and none in the A group (the eldest patients).