Postural control during prolonged standing in persons with chronic low back pain

Prolonged standing has been associated with the onset of low back pain symptoms in working populations. So far, it is unknown how individuals with chronic low back pain (CLBP) behave during prolonged unconstrained standing (PS). The aim of the present study was to analyze the control of posture by subjects with CLBP during PS in comparison to matched healthy adults. The center of pressure (COP) position of 12 CLBP subjects and 12 matched healthy controls was recorded in prolonged standing (30 min) and quiet stance tasks (60 s) on a force plate. The number and amplitude of COP patterns, the root mean square (RMS), speed, and frequency of COP sway were analyzed. Statistical analyses showed that CLBP subjects produced less Postural changes in the antero-posterior direction with decreased postural sway during the prolonged standing task in comparison to the healthy group. Only CLBP subjects were influenced by the prolonged standing task, as demonstrated by their increased COP RMS, COP speed and COP frequency in the quiet standing trial after the prolonged standing task in comparison to the pre-PS trial. The present study provides additional evidence that individuals with CLBP might have altered sensory-motor function. Their inability to generate responses similar to those of healthy subjects during prolonged standing may contribute to CLBP persistence or an increase risk of recurrent back pain episodes. Moreover, quantification of postural changes during prolonged standing could be useful to identify CLBP subjects prone to postural control deficits. (C) 2008 Elsevier B.V. All rights reserved.

Offline Detection, Identification, and Correction of Branch Parameter Errors Based on Several Measurement Snapshots

This paper proposes a three-stage offline approach to detect, identify, and correct series and shunt branch parameter errors. In Stage 1 the branches suspected of having parameter errors are identified through an Identification Index (II). The II of a branch is the ratio between the number of measurements adjacent to that branch, whose normalized residuals are higher than a specified threshold value, and the total number of measurements adjacent to that branch. Using several measurement snapshots, in Stage 2 the suspicious parameters are estimated, in a simultaneous multiple-state-and-parameter estimation, via an augmented state and parameter estimator which increases the V - theta state vector for the inclusion of suspicious parameters. Stage 3 enables the validation of the estimation obtained in Stage 2, and is performed via a conventional weighted least squares estimator. Several simulation results (with IEEE bus systems) have demonstrated the reliability of the proposed approach to deal with single and multiple parameter errors in adjacent and non-adjacent branches, as well as in parallel transmission lines with series compensation. Finally the proposed approach is confirmed on tests performed on the Hydro-Quebec TransEnergie network.

The antipyretic effect of dipyrone is unrelated to inhibition of PGE(2) synthesis in the hypothalamus

BACKGROUND AND PURPOSE Bacterial lipopolysaccharide (LPS) induces fever through two parallel pathways; one, prostaglandin (PG)-dependent and the other, PG-independent and involving endothelin-1 (ET-1). For a better understanding of the mechanisms by which dipyrone exerts antipyresis, we have investigated its effects on fever and changes in PGE(2) content in plasma, CSF and hypothalamus induced by either LPS or ET-1. EXPERIMENTAL APPROACH Rats were given (i.p.) dipyrone (120 mg center dot kg-1) or indomethacin (2 mg center dot kg-1) 30 min before injection of LPS (5 mu g center dot kg-1, i.v.) or ET-1 (1 pmol, i.c.v.). Rectal temperature was measured by tele-thermometry. PGE(2) levels were determined in the plasma, CSF and hypothalamus by elisa. KEY RESULTS LPS or ET-1 induced fever and increased CSF and hypothalamic PGE(2) levels. Two hours after LPS, indomethacin reduced CSF and hypothalamic PGE(2) but did not inhibit fever, while at 3 h it reduced all three parameters. Three hours after ET-1, indomethacin inhibited the increase in CSF and hypothalamic PGE(2) levels but did not affect fever. Dipyrone abolished both the fever and the increased CSF PGE(2) levels induced by LPS or ET-1 but did not affect the increased hypothalamic PGE(2) levels. Dipyrone also reduced the increase in the venous plasma PGE(2) concentration induced by LPS. CONCLUSIONS AND IMPLICATIONS These findings confirm that PGE(2) does not play a relevant role in ET-1-induced fever. They also demonstrate for the first time that the antipyretic effect of dipyrone was not mechanistically linked to the inhibition of hypothalamic PGE(2) synthesis.

Biomarkers of selenium status in the amazonian context: Blood, urine and sequential hair segments

Selenium (Se) is an essential element and deficit or excess of dietary Se is associated with health disorders. Relatively elevated Se levels have been reported in the Brazilian Amazon, where there are also important annual variations in the availability of different foods. The present study was conducted among six riparian communities of the Tapajos River to evaluate seasonal variations in blood and sequential hair cm Se concentrations, and to examine the relationships between Se in blood and hair, and blood and urine. Two cross-sectional studies were conducted, at the descending water (DWS, n = 259) and the rising water (RWS, n = 137) seasons, with repeated measures for a subgroup (n = 112). Blood Se (B-Se), hair Se (H-Se) and urine Se (U-Se) were determined. Match-paired analyses were used for seasonal comparisons and the method of best fit was used to describe the relationships between biomarkers. B-Se levels presented a very large range (142-2447 mu g/l) with no overall seasonal variation (median 284 and 292 mu g/l, respectively). Sequential analysis of 13 cm hair strands showed significant variations over time: Se concentrations at the DWS were significantly lower compared with the rising water season (medians: 0.7 and 0.9 mu g/g; ranges: 0.2-4.3 mu g/g and 0.2-5.4 mu g/g, respectively). At both seasons, the relationships between B-Se and H-Se were linear and highly significant (r(2) = 67.9 and 63.6, respectively), while the relationship between B-Se and U-Se was best described by a sigmoid curve. Gender, age, education and smoking did not influence Se status or biomarker relationships. Variations in H-Se suggest that there may be seasonal availability of Se sources in local food. For populations presenting a large range and/or elevated Se exposure, sequential analyses of H-Se may provide a good reflection of variations in Se status.

A university extension course in leprosy: telemedicine in the Amazon for primary healthcare

There is a high prevalence of leprosy in the Amazon region of Brazil. We have developed a distance education course in leprosy for training staff of the Family Health Teams (FHTs). The course was made available through a web portal. Tele-educational resources were mediated by professors and coordinators, and included the use of theoretical content available through the web, discussion lists, Internet chat, activity diaries, 3-D video animations (Virtual Human on Leprosy), classes in video streaming and case simulation. Sixty-five FHT staff members were enrolled. All of them completed the course and 47 participants received a certificate at the end of the course. At the end of the course, 48 course-evaluation questionnaires were answered. A total of 47 participants (98%) considered the course as excellent. The results demonstrate the feasibility of an interactive, tele-education model as an educational resource for staff in isolated regions. Improvements in diagnostic skills should increase diagnostic suspicion of leprosy and may contribute to early detection.

Novel inactivating mutations in the GH secretagogue receptor gene in patients with constitutional delay of growth and puberty

Background: A limited number of mutations in the GH secretagogue receptor gene (GHSR) have been described in patients with short stature. Objective: To analyze GHSR in idiopathic short stature (ISS) children including a subgroup of constitutional delay of growth and puberty (CDGP) patients. Subjects and methods: The GHSR coding region was directly sequenced in 96 independent patients with ISS, 31 of them with CDGP, in 150 adults, and in 197 children with normal stature. The pharmacological consequences of GHSR non-synonymous variations were established using in vitro cell-based assays. Results: Five different heterozygous point variations in GHSR were identified (c.-6 G>C, c.251G>T (p.Ser84Ile), c.505G>A (p.Ala169Thr), c.545 T>C (p.Val182Ala), and c.1072G>A (p.Ala358Thr)), all in patients with CDGP. Neither these allelic variants nor any other mutations were found in 694 alleles from controls. Functional studies revealed that two of these variations (p.Ser84Ile and p. Val182Ala) result in a decrease in basal activity that was in part explained by a reduction in cell surface expression. The p.Ser84Ile mutation was also associated with a defect in ghrelin potency. These mutations were identified in two female patients with CDGP (at the age of 13 years, their height SDS were -2.4 and -2.3). Both patients had normal progression of puberty and reached normal adult height (height SDS of -0.7 and -1.4) without treatment. Conclusion: This is the first report of GHSR mutations in patients with CDGP. Our data raise the intriguing possibility that abnormalities in ghrelin receptor function may influence the phenotype of individuals with CDGP.

Mechanisms Involved in 3 `,5 `-Cyclic Adenosine Monophosphate-Mediated Inhibition of the Ubiquitin-Proteasome System in Skeletal Muscle

Although it is well known that catecholamines inhibit skeletal muscle protein degradation, the molecular underlying mechanism remains unclear. This study was undertaken to investigate the role of beta(2)-adrenoceptors (AR) and cAMP in regulating the ubiquitin-proteasome system (UPS) in skeletal muscle. We report that increased levels of cAMP in isolated muscles, promoted by the cAMP phosphodiesterase inhibitor isobutyl methylxanthine was accompanied by decreased activity of the UPS, levels of ubiquitin-protein conjugates, and expression of atrogin-1, a key ubiquitin-protein ligase involved in muscle atrophy. In cultured myotubes, atrogin-1 induction after dexamethasone treatment was completely prevented by isobutyl methylxanthine. Furthermore, administration of clenbuterol, a selective beta(2)-agonist, to mice increased muscle cAMP levels and suppressed the fasting-induced expression of atrogin-1 and MuRF-1, atrogin-1 mRNA being much more responsive to clenbuterol. Moreover, clenbuterol increased the phosphorylation of muscle Akt and Foxo3a in fasted rats. Similar responses were observed in muscles exposed to dibutyryl-cAMP. The stimulatory effect of clenbuterol on cAMP and Akt was abolished in muscles from beta(2)-AR knockout mice. The suppressive effect of beta(2)-agonist on atrogin-1 was not mediated by PGC-1 alpha (peroxisome proliferator-activated receptor-gamma coactivator 1 alpha known to be induced by beta(2)-agonists and previously shown to inhibit atrogin-1 expression), because food-deprived PGC-1 alpha knockout mice were still sensitive to clenbuterol. These findings suggest that the cAMP increase induced by stimulation of beta(2)-AR in skeletal muscles from fasted mice is possibly the mechanism by which catecholamines suppress atrogin-1 and the UPS, this effect being mediated via phosphorylation of Akt and thus inactivation of Foxo3. (Endocrinology 150: 5395-5404, 2009)

Behavioural responses of heifers to ACTH injections

The objective of this study was to investigate behavioural changes in Holstein heifers caused by exogenous adrenocorticotropic hormone (ACTH) administration. Twelve 11-month-old heifers were submitted to either a single saline or ACTH injection and then the treatments were switched after 3 days (n = 12 heifers/treatment). Heifers were in full view throughout the experimental period and recordings started immediately after ACTH and saline administration (injection corresponded to time 0 min), with general activity patterns of each heifer recorded on videotape for 24 h. Behavioural results during the first two experimental hours showed that heifers were less active and spent more time lying following ACTH than after saline treatment (P = 0.04). Also, heifers spent significantly less time ruminating immediately following ACTH injection (P = 0.05). However, feed intake measured after 4 and 24 h was similar between treatments (P > 0.05). Overall, there was no significant influence of ACTH treatment on frequency or duration of behaviours during the 4- and 24-h periods following injection (P > 0.05). The rapid and minimal effect of ACTH injection on behaviour suggests that peripheral administration of ACTH can be used to measure reactivity of the adrenal cortex without inducing biologically significant consequences. (C) 2010 Elsevier B.V. All rights reserved.

Telehealth in audiology: The need and potential to reach underserved communities

Permanent hearing loss is a leading global health care burden, with 1 in 10 people affected to a mild or greater degree. A shortage of trained healthcare professionals and associated infrastructure and resource limitations mean that hearing health services are unavailable to the majority of the world population. Utilizing information and communication technology in hearing health care, or tele-audiology, combined with automation offer unique opportunities for improved clinical care, widespread access to services, and more cost-effective and sustainable hearing health care. Tele-audiology demonstrates significant potential in areas such as education and training of hearing health care professionals, paraprofessionals, parents, and adults with hearing disorders; screening for auditory disorders; diagnosis of hearing loss; and intervention services. Global connectivity is rapidly growing with increasingly widespread distribution into underserved communities where audiological services may be facilitated through telehealth models. Although many questions related to aspects such as quality control, licensure, jurisdictional responsibility, certification and reimbursement still need to be addressed; no alternative strategy can currently offer the same potential reach for impacting the global burden of hearing loss in the near and foreseeable future.

The development of a pilot telemedicine network in Scotland: lessons learned

A pilot telemedicine network was established in 11 sites using funding provided by the Department of Trade and Industry in the UK. The main purpose of the project was to develop and evaluate clinical and educational links between central and peripheral sites in Scotland, The results were very encouraging, and clinical services were established in accident and emergency medicine, tele-ultrasound and clinical psychology. An undergraduate medical teaching service was also successfully established. All of these services are to be continued after the completion of the project. Many lessons were learned during the establishment of this network which will be useful in future projects. These included the importance of training for telemedicine users, the importance of identifying a telemedicine champion, the pitfall of health economics and the fact that services must be needs driven.

Realtime fetal ultrasound by telemedicine in Queensland. A successful venture?

We have established a realtime fetal tele-ultrasound consultation service in Queensland, which has been integrated into our routine clinical practice, The service, which uses ISDN transmission at 384 kbit/s, allows patients in Townsville to be examined by subspecialists in Brisbane, 1500 km away. For the 90 tele-ultrasound consultations performed for the first 71 patients, 90% of the babies have been delivered, and outcome data have been received on all the pregnancies. All significant anomalies and diagnoses have been confirmed. The referring clinicians would have physically referred 24 of the 71 patients to Brisbane in the absence of telemedicine. A crude cost-benefit calculation suggests that the tele-ultrasound service resulted in a net saving of A$6340, and at the same time enabled almost four times the number of consultations to be carried out.

Advances in neurotrauma in Australia 1970-2000

The management of neurotrauma in Australia has been one of the significant public health triumphs during the last 30 years of the 20th century. State and national government agencies act in a coordinated fashion to collect data and to promote research on how to manage neurotrauma patients. Between 1970 and 1995, fatalities from road accidents decreased by 47%. Hospital admissions have decreased by 40% despite a 40% increase in the population and a 120% increase in registered vehicles. Fatalities per 10,000 registered vehicles were 8.05% in 1970 and they fell to 1.84% per vehicles in 1995, while fatalities per 10;000 population were 3 in 1970 falling to 1.11 in 1995. Hospitalization from road crashes decreased 23% between March 1988 and March 1997. Public education has steadily improved, backed by the state public health sources. A uniform code of road safety laws has been adopted, backed by legislation and legal penalties and increasing police enforcement. Clinical care of patients has improved as a result of faster communications, tele-medicine, trauma systems, the CT scanner; intensive care units, and improved monitoring. Patient rehabilitation and counseling are now carried out at units accredited by the Australian Council on Health Care Standards.

Randomized comparison of the quality of realtime fetal ultrasound images transmitted by ISDN and by IP videoconferencing

We compared the quality of realtime fetal ultrasound images transmitted using ISDN and IP networks. Four experienced obstetric ultrasound specialists viewed standard recordings in a randomized trial and rated the appearance of 30 fetal anatomical landmarks, each on a seven-point scale. A total of 12 evaluations were performed for various combinations of bandwidths (128, 384 or 768 kbit/s) and networks (ISDN or IF). The intraobserver coefficient of variation was 2.9%, 5.0%, 12.7% and 14.7% for the four observers. The mean overall ratings by each of the four observers were 4.6, 4.8, 5.0 and 5.3, respectively (a rating of 4 indicated satisfactory visualization and 7 indicated as good as the original recording). Analysis of variance showed that there were no significant interobserver variations nor significant differences in the mean scores for the different types of videoconferencing machines used. The most significant variable affecting the mean score was the bandwidth used. For ISDN, the mean score was 3.7 at 128 kbit/s, which was significantly worse than the mean score of 4.9 at 384 kbit/s, which was in turn significantly worse than the mean score of 5.9 at 768 kbit/s. The mean score for transmission using IP was about 0.5 points lower than that using ISDN across all the different bandwidths, but the differences were not significant. It appears that IP transmission in a private (non-shared) network is an acceptable alternative to ISDN for fetal tele-ultrasound and one deserving further study.

O contributo da rotoscopia na relação entre cinema de animação e artes plásticas

A par de uma curta-metragem de animação intitulada Tele-sofia, o prosente trabalho enfatizará a importância do desenho como base das artes plásticas. Partindo deste pressuposto, a identificação, compreensão e inclusão das componentes estruturais do desenho poderão ser fortes adjuvantes na reconversão de práticas tendencialmente mais tecnologizadas em poéticas dos materiais e do atelier, distintivas das artes plásticas. Assim, na direta medida em que a rotoscopia se fundamente no desenho responsivo - como uma extensão das possibilidades do desenho de modelo - ir-se-á integrando no campo artístico, tornando a obra resultante numa animação de experiências plásticas. Afinal, o desenho não se confina à perfeição reprodução mecânica da realidade - a mimesis - ele requer interpretações idiossincráticas e uma profunda empatia com o referente, dados apenas registados por um instrumento sensível: o artista.

Marcação CE de dispositivos médicos e segurança em software

Com o crescente aumento da Teleradiologia, sentiu-se necessidade de criar mais e melhores softwares para sustentar esse crescimento. O presente trabalho pretende abordar a temática da certificação de software e a sua marcação CE, pois para dar entrada no mercado Europeu todos os Dispositivos Médicos (DM) têm de estar devidamente certificados. Para efetuar a marcação CE e a certificação serão estudadas normas e normativos adequados para marcação de DM ao nível Europeu e também dos Estados Unidos da América. A temática da segurança de dados pessoais será também estudada de forma a assegurar que o dispositivo respeite a legislação em vigor. Este estudo tem como finalidade a certificação de um software proprietário da efficientia sysPACS, um serviço online abrangente, que permite a gestão integrada do armazenamento e distribuição de imagens médicas para apoio ao diagnóstico.