Percutaneous sciatic nerve block with tramadol induces analgesia and motor blockade in two animal pain models

Local anesthetic efficacy of tramadol has been reported following intradermal application. Our aim was to investigate the effect of perineural tramadol as the sole analgesic in two pain models. Male Wistar rats (280-380 g; N = 5/group) were used in these experiments. A neurostimulation-guided sciatic nerve block was performed and 2% lidocaine or tramadol (1.25 and 5 mg) was perineurally injected in two different animal pain models. In the flinching behavior test, the number of flinches was evaluated and in the plantar incision model, mechanical and heat thresholds were measured. Motor effects of lidocaine and tramadol were quantified and a motor block score elaborated. Tramadol, 1.25 mg, completely blocked the first and reduced the second phase of the flinching behavior test. In the plantar incision model, tramadol (1.25 mg) increased both paw withdrawal latency in response to radiant heat (8.3 ± 1.1, 12.7 ± 1.8, 8.4 ± 0.8, and 11.1 ± 3.3 s) and mechanical threshold in response to von Frey filaments (459 ± 82.8, 447.5 ± 91.7, 320.1 ± 120, 126.43 ± 92.8 mN) at 5, 15, 30, and 60 min, respectively. Sham block or contralateral sciatic nerve block did not differ from perineural saline injection throughout the study in either model. The effect of tramadol was not antagonized by intraperitoneal naloxone. High dose tramadol (5 mg) blocked motor function as well as 2% lidocaine. In conclusion, tramadol blocks nociception and motor function in vivo similar to local anesthetics.

Surgical treatment of type I neuritis in a teenage boy with borderline tuberculoid leprosy

Exacerbation of the immune response against Mycobacterium leprae can lead to neuritis, which is commonly treated via immunosuppression with corticosteroids. Early neurolysis may be performed concurrently, especially in young patients with a risk of functional sequelae. We report the case of a young patient experienced intense pain in the left elbow one year after the treatment of tuberculoid-tuberculoid leprosy. The pain was associated with paresthesias in the ulnar edge and left ulnar claw. After evaluation, the diagnosis was changed to borderline tuberculoid leprosy accompanied with neuritis of the left ulnar nerve. Early neurolysis resulted in rapid reduction of the pain and recovery of motor function.

A functional study of caustic strictures of the esophagus in children

The objective of the present study was to assess esophageal motor function in 21 children (7.5 ± 2.9 years) with caustic strictures. Esophageal manometry was performed using a water-infusion system interfaced with a polygraph and displayed on a computer screen. The data were compared with those obtained from 9 healthy children. Radionuclide transit was determined by studying deglutition of a single bolus of 99mTc pertechnetate in 10 ml of water. Non-peristaltic low-amplitude and long-duration waves were the most common findings detected in patients with strictures longer than 20% of esophageal length (N = 11). Compared with the control group, these patients presented lower mean amplitude and longer mean duration of waves (24.4 ± 11.2 vs 97.9 ± 23.7 mmHg, P < 0.05, and 6.7 ± 2.4 vs 1.6 ± 0.1 s, P < 0.05, respectively). Six patients presented low-amplitude waves just below the constricted site. Ten children presented delayed esophageal transit. There was an association between dysphagia and abnormalities on manometry (P = 0.02) and between symptoms and scintigraphy data (P = 0.01). Dysphagia in caustic strictures is due to esophageal motility abnormalities, which are closely related to the scarred segment.

Schwann cells for spinal cord repair

The complex nature of spinal cord injury appears to demand a multifactorial repair strategy. One of the components that will likely be included is an implant that will fill the area of lost nervous tissue and provide a growth substrate for injured axons. Here we will discuss the role of Schwann cells (SCs) in cell-based, surgical repair strategies of the injured adult spinal cord. We will review key studies that showed that intraspinal SC grafts limit injury-induced tissue loss and promote axonal regeneration and myelination, and that this response can be improved by adding neurotrophic factors or anti-inflammatory agents. These results will be compared with several other approaches to the repair of the spinal cord. A general concern with repair strategies is the limited functional recovery, which is in large part due to the failure of axons to grow across the scar tissue at the distal graft-spinal cord interface. Consequently, new synaptic connections with spinal neurons involved in motor function are not formed. We will highlight repair approaches that did result in growth across the scar and discuss the necessity for more studies involving larger, clinically relevant types of injuries, addressing this specific issue. Finally, this review will reflect on the prospect of SCs for repair strategies in the clinic.

Influence of intrauterine and extrauterine growth on neurodevelopmental outcome of monozygotic twins

There have been indications that intrauterine and early extrauterine growth can influence childhood mental and motor function. The objective of the present study was to evaluate the influence of intrauterine growth restriction and early extrauterine head growth on the neurodevelopmental outcome of monozygotic twins. Thirty-six monozygous twin pairs were evaluated at the corrected age of 12 to 42 months. Intrauterine growth restriction was quantified using the fetal growth ratio. The effects of birth weight ratio, head circumference at birth and current head circumference on mental and motor outcomes were estimated using mixed-effect linear regression models. Separate estimates of the between (interpair) and within (intrapair) effects of each measure on development were thus obtained. Neurodevelopment was assessed with the Bayley Scales of Infant Development, 2nd edition, by a psychologist blind to the exposure. A standardized neurological examination was performed by a neuropediatrician who was unaware of the exposures under investigation. After adjustment, birth weight ratio and head circumference at birth were not associated with motor or mental outcomes. Current head circumference was associated with mental but not with motor outcomes. Only the intrapair twin effect was significant. An increase of 1 cm in current head circumference of one twin compared with the other was associated with 3.2 points higher in Mental Developmental Index (95%CI = 1.06-5.32; P < 0.03). Thus, no effect of intrauterine growth was found on cognition and only postnatal head growth was associated with cognition. This effect was not shared by the co-twin.

An interleukin-33/ST2 signaling deficiency reduces overt pain-like behaviors in mice

Interleukin (IL)-33, the most recent member of the IL family of cytokines, signals through the ST2 receptor. IL-33/ST2 signaling mediates antigen challenge-induced mechanical hyperalgesia in the joints and cutaneous tissues of immunized mice. The present study asked whether IL-33/ST2 signaling is relevant to overt pain-like behaviors in mice. Acetic acid and phenyl-p-benzoquinone induced significant writhing responses in wild-type (WT) mice; this overt nociceptive behavior was reduced in ST2-deficient mice. In an antigen-challenge model, ST2-deficient immunized mice had reduced induced flinch and licking overt pain-like behaviors. In the formalin test, ST2-deficient mice also presented reduced flinch and licking responses, compared with WT mice. Naive WT and ST2-deficient mice presented similar responses in the rota-rod, hot plate, and electronic von Frey tests, indicating no impairment of motor function or alteration in basal nociceptive responses. The results demonstrate that IL-33/ST2 signaling is important in the development of overt pain-like behaviors.

Stretch-induced nerve injury: a proposed technique for the study of nerve regeneration and evaluation of the influence of gabapentin on this model

The rat models currently employed for studies of nerve regeneration present distinct disadvantages. We propose a new technique of stretch-induced nerve injury, used here to evaluate the influence of gabapentin (GBP) on nerve regeneration. Male Wistar rats (300 g; n=36) underwent surgery and exposure of the median nerve in the right forelimbs, either with or without nerve injury. The technique was performed using distal and proximal clamps separated by a distance of 2 cm and a sliding distance of 3 mm. The nerve was compressed and stretched for 5 s until the bands of Fontana disappeared. The animals were evaluated in relation to functional, biochemical and histological parameters. Stretching of the median nerve led to complete loss of motor function up to 12 days after the lesion (P<0.001), compared to non-injured nerves, as assessed in the grasping test. Grasping force in the nerve-injured animals did not return to control values up to 30 days after surgery (P<0.05). Nerve injury also caused an increase in the time of sensory recovery, as well as in the electrical and mechanical stimulation tests. Treatment of the animals with GBP promoted an improvement in the morphometric analysis of median nerve cross-sections compared with the operated vehicle group, as observed in the area of myelinated fibers or connective tissue (P<0.001), in the density of myelinated fibers/mm2 (P<0.05) and in the degeneration fragments (P<0.01). Stretch-induced nerve injury seems to be a simple and relevant model for evaluating nerve regeneration.

A forced running wheel system with a microcontroller that provides high-intensity exercise training in an animal ischemic stroke model

We developed a forced non-electric-shock running wheel (FNESRW) system that provides rats with high-intensity exercise training using automatic exercise training patterns that are controlled by a microcontroller. The proposed system successfully makes a breakthrough in the traditional motorized running wheel to allow rats to perform high-intensity training and to enable comparisons with the treadmill at the same exercise intensity without any electric shock. A polyvinyl chloride runway with a rough rubber surface was coated on the periphery of the wheel so as to permit automatic acceleration training, and which allowed the rats to run consistently at high speeds (30 m/min for 1 h). An animal ischemic stroke model was used to validate the proposed system. FNESRW, treadmill, control, and sham groups were studied. The FNESRW and treadmill groups underwent 3 weeks of endurance running training. After 3 weeks, the experiments of middle cerebral artery occlusion, the modified neurological severity score (mNSS), an inclined plane test, and triphenyltetrazolium chloride were performed to evaluate the effectiveness of the proposed platform. The proposed platform showed that enhancement of motor function, mNSS, and infarct volumes was significantly stronger in the FNESRW group than the control group (P<0.05) and similar to the treadmill group. The experimental data demonstrated that the proposed platform can be applied to test the benefit of exercise-preconditioning-induced neuroprotection using the animal stroke model. Additional advantages of the FNESRW system include stand-alone capability, independence of subjective human adjustment, and ease of use.

Options listing and the volatility of the underling asset: a study on the derivative market function

There are basic misunderstandings on derivative markets. Some professionals believe that they are a kind of casinos and have no utility for the investors. This work looks at the effects of options introduction in the Brazilian market, seeking for another benefit for this introduction: changes in the stocks risk leveI. Our results are the same found in the US and other markets: the options introduction reduces the stocks volatility. We also found that there is a slight indication that the volatility becames more stochastic with this alternative.

Alguns aspectos epidemiológicos da mortalidade por acidentes de trânsito de veículo a motor na Cidade de São Paulo, Brasil

Foram estudadas algumas características dos óbitos por acidentes de trânsito de veículos a motor, no município de São Paulo, ocorridos entre 1.° de janeiro a 31 de dezembro de 1970. Todas as características do falecido e do acidente foram coletadas a partir dos dados registrados nos laudos de necrópsias existentes no Instituto Médico Legal. O estudo evidenciou que a mortalidade por acidentes de veículo a motor é alta, maior no sexo masculino, aumenta com a idade, sendo que o maior coeficiente foi para maiores de 60 anos. A zona da cidade com maior número de acidentes é a zona Sul, existindo áreas (distritos policiais) e vias públicas preferenciais quanto a ocorrência, em todas as 4 zonas do município; a maior ocorrência de acidentes foi aos sábados e domingos; os pedestres compreendem a grande maioria dos falecidos; proporção apreciável dos falecidos recebeu atendimento hospitalar após o acidente. Foram relacionados também o número total de acidentes, vítimas e mortes mostrando que para cada 100 acidentes ocorreram 62,50 vítimas e 5,13 mortes, e para cada 100 vítimas, 18, 22 mortes.

Aspectos epidemiológicos dos acidentes fatais a veículo a motor na cidade do Salvador (Bahia), Brasil

Foi realizado um estudo com o objetivo de descrever certos aspectos epidemiológicos dos acidentes de trânsito de veículo a motor, na cidade do Salvador, Bahia, Brasil, o qual envolveu coleta de informações no Departamento de Trânsito (DETRAN) e no Instituto de Medicina Legal. Ficou demonstrado que os acidentes de trânsito de veículo a motor são mais freqüentes ao fim da tarde e concentram-se, sobretudo, no fim de semana, isto é, sábado e domingo. Motoristas do sexo masculino foram muito mais freqüentemente envolvidos em acidentes de trânsito do que os do sexo feminino. Foi concluído que os acidentes fatais envolvendo pedestres constituem-se importante problema urbano necessitando cuidadosa atenção por parte de educadores e dos serviços públicos responsáveis pelo setor do trânsito. Foi sugerida a necessidade de melhorar e tornar mais uniforme o sistema de notificação e classificação dos acidentes de veículo a motor pelo DETRAN da cidade do Salvador.

Traumatismo crânio-encefálico: diferenças das vítimas pedestres e ocupantes de veículos a motor

OBJETIVO: Caracterizar as diferenças das vítimas com diagnóstico de traumatismo crânio-encefálico envolvidas em diferentes condições, em acidentes de trânsito de veículo a motor e evidenciar indicadores para prevenção e seu atendimento. MÉTODO: Foram analisados os prontuários de todas as vítimas com diagnóstico de trauma crânio-encefálico, assistidas em hospital de referência para atendimento do trauma, entre março e junho de 1993. A população foi de 156 vítimas, sendo 80 pedestres, 50 ocupantes de veículos a motor, exceto de moto e, 26 motociclistas ou passageiros de motos. RESULTADOS E CONCLUSÕES: Os resultados mostraram que a mortalidade entre pedestres foi a mais alta entre os três grupos (25,0%). Os óbitos ocorrem em 19,2% dos ocupantes de motocicleta e 8,0% dos ocupantes de demais veículos a motor. Foram observadas diferenças estatísticas entre os grupos quando a variável gravidade do trauma crânio-encefálico foi analisado. Análise de certas variáveis mostraram importantes diferenças na distribuição dos três grupos.

Effects of the length and timing of nighttime naps on task performance and physiological function

OBJECTIVE: To examine the effects of the length and timing of nighttime naps on performance and physiological functions, an experimental study was carried out under simulated night shift schedules. METHODS: Six students were recruited for this study that was composed of 5 experiments. Each experiment involved 3 consecutive days with one night shift (22:00-8:00) followed by daytime sleep and night sleep. The experiments had 5 conditions in which the length and timing of naps were manipulated: 0:00-1:00 (E60), 0:00-2:00 (E120), 4:00-5:00 (L60), 4:00-6:00 (L120), and no nap (No-nap). During the night shifts, participants underwent performance tests. A questionnaire on subjective fatigue and a critical flicker fusion frequency test were administered after the performance tests. Heart rate variability and rectal temperature were recorded continuously during the experiments. Polysomnography was also recorded during the nap. RESULTS: Sleep latency was shorter and sleep efficiency was higher in the nap in L60 and L120 than that in E60 and E120. Slow wave sleep in the naps in E120 and L120 was longer than that in E60 and L60. The mean reaction time in L60 became longer after the nap, and faster in E60 and E120. Earlier naps serve to counteract the decrement in performance and physiological functions during night shifts. Performance was somewhat improved by taking a 2-hour nap later in the shift, but deteriorated after a one-hour nap. CONCLUSIONS: Naps in the latter half of the night shift were superior to earlier naps in terms of sleep quality. However performance declined after a 1-hour nap taken later in the night shift due to sleep inertia. This study suggests that appropriate timing of a short nap must be carefully considered, such as a 60-min nap during the night shift.

Oportunidades do ambiente domiciliar para o desenvolvimento motor

OBJETIVO: Avaliar as oportunidades presentes no ambiente domiciliar para o desenvolvimento motor de lactentes. MÉTODOS: Estudo epidemiológico de base populacional, transversal, realizado com 239 lactentes com idade entre três e 18 meses, residentes no município de Juiz de Fora, MG, em 2010. Os participantes foram selecionados por amostragem aleatória estratificada, conglomerada, em múltiplos estágios. Para avaliar a qualidade e quantidade de estímulo motor no ambiente domiciliar foi utilizado o instrumento Affordance in the Home Environment for Motor Development - Infant Scale. Procedeu-se a análise bivariada com aplicação do teste qui-quadrado, seguida de regressão logística multinomial para verificar a associação entre as oportunidades presentes no domicílio e fatores biológicos, comportamentais, demográficos e socioeconômicos. RESULTADOS: As oportunidades de estimulação ambiental foram relativamente baixas. Na análise bivariada, para a faixa etária de três a nove meses, foi encontrada associação com os fatores: ordem de nascimento (p = 0,06), classificação socioeconômica (p = 0,08), renda mensal (p = 0,06) e renda per capita (p = 0,03). No modelo de regressão, prevaleceu a classificação socioeconômica (RC = 7,46; p = 0,03). Para a faixa etária de dez a 18 meses, os fatores associados, na análise bivariada, foram: estado civil materno (p < 0,01), convívio da criança com o pai (p = 0,08), chefe da família (p = 0,04), número de pessoas no domicílio (p = 0,05), escolaridade materna (p < 0,01) e paterna (p < 0,01), classificação socioeconômica (p < 0,01) e renda per capita (p = 0,03). No modelo de regressão, o estado civil materno (RC = 4,83; p = 0,02), escolaridade materna (RC = 0,29; p = 0,03) e paterna (RC = 0,33; p = 0,04) permaneceram associados às oportunidades de estimulação ambiental. CONCLUSÕES: A união estável dos pais, maior escolaridade materna e paterna e maior nível econômico foram os fatores associados às melhores oportunidades de estimulação motora no lar.

Content validity and reliability of test of gross motor development in Chilean children

ABSTRACT OBJECTIVE To validate a Spanish version of the Test of Gross Motor Development (TGMD-2) for the Chilean population. METHODS Descriptive, transversal, non-experimental validity and reliability study. Four translators, three experts and 92 Chilean children, from five to 10 years, students from a primary school in Santiago, Chile, have participated. The Committee of Experts has carried out translation, back-translation and revision processes to determine the translinguistic equivalence and content validity of the test, using the content validity index in 2013. In addition, a pilot implementation was achieved to determine test reliability in Spanish, by using the intraclass correlation coefficient and Bland-Altman method. We evaluated whether the results presented significant differences by replacing the bat with a racket, using T-test. RESULTS We obtained a content validity index higher than 0.80 for language clarity and relevance of the TGMD-2 for children. There were significant differences in the object control subtest when comparing the results with bat and racket. The intraclass correlation coefficient for reliability inter-rater, intra-rater and test-retest reliability was greater than 0.80 in all cases. CONCLUSIONS The TGMD-2 has appropriate content validity to be applied in the Chilean population. The reliability of this test is within the appropriate parameters and its use could be recommended in this population after the establishment of normative data, setting a further precedent for the validation in other Latin American countries.