Development and field validation of a reverse transcription loop-mediated isothermal amplification assay (RT-LAMP) for the rapid detection of chikungunya virus in patient and mosquito samples.

OBJECTIVES: We aimed to develop a reverse transcription loop-mediated isothermal amplification (RT-LAMP) platform for the rapid detection of chikungunya virus (CHIKV) in both patient and mosquito samples from Brazil. METHODS: We optimized an RT-LAMP assay and then evaluated the specificity and sensitivity using visual detection. In comparison with the RT-qPCR reference method, we validated the utility of this assay as a molecular diagnostic test in a reference laboratory for arbovirus diagnostics using 100 serum samples collected from suspected CHIKV cases. RESULTS: Our RT-LAMP assay specifically detected CHIKV without cross-reactivity against other arboviruses. The limit of detection of our RT-LAMP was estimated in -1.18 PFU (confidence interval [CI] ranging from -2.08 to 0.45), resulting in a similar analytical sensitivity when directly compared with the reference standard RT-qPCR assay. Then, we demonstrate the ability of our RT-LAMP assay to detect the virus in different human specimens (serum, urine, and saliva), and crude lysate of Aedes aegypti mosquitoes in as little as 20-30 minutes and without a separate RNA isolation step. Lastly, we showed that our RT-LAMP assay could be lyophilized and reactivated by adding water, indicating potential for room-temperature storage. Our RT-LAMP had a clinical sensitivity of 100% (95% CI, 90.97-100.00%), clinical specificity of 96.72% (95% CI, 88.65-99.60%), and overall accuracy of 98.00% (95% CI, 92.96-99.76%). DISCUSSION: Taken together, these findings indicate that the RT-LAMP assay reported here solves important practical drawbacks to the deployment of molecular diagnostics in the field and can be used to improve testing capacity, particularly in low- and middle-income countries.

Increased interregional virus exchange and nucleotide diversity outline the expansion of the chikungunya virus ECSA lineage in Brazil.

The emergence and reemergence of mosquito-borne diseases in Brazil such as Yellow Fever, Zika, Chikungunya, and Dengue have had serious impacts on public health. Concerns have been raised due to the rapid dissemination of the chikungunya virus (CHIKV) across the country since its first detection in 2014 in Northeast Brazil. Faced with this scenario, on-site training activities in genomic surveillance carried out in partnership with the National Network of Public Health Laboratories have led to the generation of 422 CHIKV genomes from 12 Brazilian states over the past two years (2021-2022), a period that has seen more than 312 thousand chikungunya fever cases reported in the country. These new genomes increased the amount of available data and allowed a more comprehensive characterization of the dispersion dynamics of the CHIKV East-Central-South-African (ECSA) lineage in Brazil. Tree branching patterns revealed the emergence and expansion of two distinct subclades. Phylogeographic analysis indicated that the northeast region has been the leading hub of virus spread towards other regions. Increased frequency of C>T transitions among the new genomes suggested that host restriction factors from the immune system such as ADAR and AID/APOBEC deaminases might be driving CHIKV ECSA lineage genetic diversity in Brazil.

Increased interregional virus exchange and nucleotide diversity outline the expansion of chikungunya virus in Brazil.

The emergence and reemergence of mosquito-borne diseases in Brazil such as yellow fever, zika, chikungunya, and dengue have had serious impacts on public health. Concerns have been raised due to the rapid dissemination of the chikungunya virus across the country since its first detection in 2014 in Northeast Brazil. In this work, we carried out on-site training activities in genomic surveillance in partnership with the National Network of Public Health Laboratories that have led to the generation of 422 chikungunya virus genomes from 12 Brazilian states over the past two years (2021-2022), a period that has seen more than 312 thousand chikungunya fever cases reported in the country. These genomes increased the amount of available data and allowed a more comprehensive characterization of the dispersal dynamics of the chikungunya virus East-Central-South-African lineage in Brazil. Tree branching patterns revealed the emergence and expansion of two distinct subclades. Phylogeographic analysis indicated that the northeast region has been the leading hub of virus spread towards other regions. Increased frequency of C > T transitions among the new genomes suggested that host restriction factors from the immune system such as ADAR and AID/APOBEC deaminases might be driving the genetic diversity of the chikungunya virus in Brazil.

Field validation of the performance of paper-based tests for the detection of the Zika and chikungunya viruses in serum samples.

In low-resource settings, resilience to infectious disease outbreaks can be hindered by limited access to diagnostic tests. Here we report the results of double-blinded studies of the performance of paper-based diagnostic tests for the Zika and chikungunya viruses in a field setting in Latin America. The tests involved a cell-free expression system relying on isothermal amplification and toehold-switch reactions, a purpose-built portable reader and onboard software for computer vision-enabled image analysis. In patients suspected of infection, the accuracies and sensitivities of the tests for the Zika and chikungunya viruses were, respectively, 98.5% (95% confidence interval, 96.2-99.6%, 268 serum samples) and 98.5% (95% confidence interval, 91.7-100%, 65 serum samples) and approximately 2 aM and 5 fM (both concentrations are within clinically relevant ranges). The analytical specificities and sensitivities of the tests for cultured samples of the viruses were equivalent to those of the real-time quantitative PCR. Cell-free synthetic biology tools and companion hardware can provide de-centralized, high-capacity and low-cost diagnostics for use in low-resource settings.

MICRO-ELIMINATION OF HEPATITIS C IN THE INCARCERATED POPULATION: IS IT REALLY POSSIBLE?

According to the World Health Organization, 71 million people live with chronic hepatitis C. The treatment of this disease requires assistance from specialized physicians and a highly complex health care system. The prison population has been recognized as being at a high risk of acquiring confinement-related infections, including viral hepatitis. Hepatitis C virus (HCV) infection is a primary cause of death owing to liver disease among liberty-deprived individuals. Generally, prisons do not have adequate isolation wards for persons with communicable diseases, and overcrowding is a risk factor for this population. Besides prison overcrowding, violence, poor sanitary conditions, low socioeconomic status, social isolation, and emotional instability are factors that can lead detainees to adopt unhealthy habits that make them more susceptible to infections, including HCV, and complicate effective treatment. The Criminal Execution Law 7, 210 of July 11, 1984, in Article 14, grants preventive and curative medical, dental, and pharmacological healthcare to detainees. However, adequate hepatitis C treatment is rarely provided at prisons owing to social stigma and lack of knowledge on the severity of this condition or because most detainees are unaware of their condition. Given the multiple limitations imposed by the prison system model, implementing measures to treat diseases effectively is challenging. However, it is possible to eliminate hepatitis C in prisons in the long term through the coordinated action of public health institutions and the prison system.

Eugenol induces body immobilization yet evoking an increased neuronal excitability in fish during short-term baths.

Several studies have suggested eugenol as a suitable anaesthetic for fish. However, it has also been regarded as a toxic and aversive substance to several aquatic organisms, including fish. This study sought to assess the eugenol-induced behavioural alterations and its seizurogenic potential to fish. Moreover, a distinctive methodology for an in vivo evaluation of the brain activity was also presented. Prior to the evaluation of eugenol-induced responses, fish were exposed to pentylenetetrazole (PTZ), to characterize any seizure-like patterns. Antagonizing responses to PTZ were assessed in fish receiving diazepam (BDZ) and subsequently exposed to PTZ. Tambaqui fish juveniles, Colossoma macropomum (15.8 ± 2.8 g) were used as models and assayed as follows: (i) fish exposed to PTZ (15 mM) and (ii) fish receiving a dose of BDZ (10 mg Kg-1) and later exposed to PTZ (15 mM) (BDZ-PTZ group). Thereafter, fish were evaluated throughout (iii) eugenol exposure at 65 µL L-1 (ethanolic solution) and recovery. Control fish and a vehicle control group (ethanol at 585 µL L-1) were also established. PTZ baths elicited body immobilization preceded by hyperactivity in a stereotyped seizure-like behaviour with increased EEG wave amplitude and frequency. PTZ effects in the brain were attenuated by a pre-administration of BDZ. Upon eugenol exposure, tambaqui had an intense neuronal excitability, showing a clonus-like seizure behaviour, also corroborated by the EEG patterns, which were consistent with a seizure-like response. Responses of eugenol-exposed fish resembled those of the PZT-exposed animals, with epileptiform discharges. EMG was in line with the EEG modulation, showing increased tracing oscillations and higher mean amplitudes in PTZ-exposed fish whereas in BDZ-PTZ group muscle contraction was less frequent and powerful. Fish exposed to eugenol showed initially some muscle activity followed by a loss of muscle tonus over time. In summary, our results showed that upon eugenol exposure, although a time-dependent body immobilization was attained, fish presented an intense neuronal excitability comparable to that evoked by PTZ. Eugenol failed to promote depression of the CNS and therefore may be not suitable to be used for general anaesthesia of C. macropomum. As eugenol could be implicated in seizurogenesis and be potentially toxic to the fish brain, protocols suggesting the broad use of eugenol for short-term anaesthesia or euthanasia of fish should be carefully revised, as it raises important concerns in terms of ethics and fish welfare.

Electrocorticographic description of the effects of anticonvulsant drugs used to treat lidocaine-induced seizures.

INTRODUCTION: Local anesthetics are widely used in clinical practice. While toxicity is rare, these drugs can cause potentially lethal seizures. OBJECTIVE: In the present study, we investigated the electrocorticographic (ECoG) and electromyographic patterns of seizures induced by acute lidocaine (LA) toxicity and treated with anticonvulsant drugs. The study used adult male Wistar rats to describe of the seizure-related behavior of LA and investigated the treatment with anticonvulsant drugs. RESULTS: The use of LA resulted in clear changes in the ECoG pattern, which presented characteristics of Status epilepticus, with increased intensity in all brainwaves. The decomposition of the cerebral waves showed an increase in the beta and gamma waves that may be related to tonic-clonic seizure. Although the treatment with anticonvulsants drugs reduces the power of brainwaves at frequencies between 1 and 40 Hz compared to the LA group, but only diazepam (DZP) was able to decrease the intensity of oscillations. The muscle contraction power also indicated a difference in the effectiveness of the three treatments. CONCLUSION: The sum of the evidence indicates that LA causes status epilepticus and that DZP is the most effective treatment for the control of these seizures, by restoring the systemic values to levels close to those recorded in the control group.

Characterization of electrocorticographic, electromyographic and electrocardiographic recordings after the use of caffeine in Wistar rats.

OBJECTIVE: To describe electrocorticographic, electromyographic and electrocardiographic profiles to report the electrophysiological effects of caffeine in Wistar rats. METHODS: Male adult Wistar rats weighing 230g to 250g were used. Rats were allocated to one of two groups, as follows: Group 1, Control, intraperitoneal injection of 0.9% saline solution (n=27); and Group 2, treated with intraperitoneal injection of caffeine (50mg/kg; n=27). The rats were submitted to electrocorticographic, electromyographic and electrocardiographic assessment. RESULTS: Brain oscillations (delta, theta, alpha, beta and gamma) in the frequency range up to 40Hz varied after caffeine administration to rats. Powers in delta and theta oscillations ranges were preponderant. The contractile force of the skeletal striated and cardiac muscles increased. Electrocardiogram analysis revealed shorter RR, QRS and QT intervals under the effect of caffeine. CONCLUSION: In the central nervous system, there was an increase in the delta, theta and alpha amplitude spectrum, which are related to memory encoding and enhanced learning. With regard to skeletal muscle, increased contraction of the gastrocnemius muscle was demonstrated, a clear indication of how caffeine can be used to enhance performance of some physical activities. Electrocardiographic changes observed after caffeine administration are primarily related to increased heart rate and energy consumption.

Leptin Levels and Q223R Leptin Receptor Gene Polymorphism in Obese Mexican Young Adults.

INTRODUCTION: The Q223R polymorphism of the leptin receptor (LEPR) gene is one of the most common polymorphisms and it is believed to be associated with a damaged capacity of LEPR signaling and with high circulating leptin levels. METHODS: An observational, cross-sectional, analytical study was carried out in the Autonomous University of Ciudad Juarez, Mexico, where a sample of young adult participants (ranging from 18 to 30 years of age) was obtained. They were classified based on the results of body mass index: non-obese, and overweight/obese. The polymorphic variant was determined by Polymerase Chain Reaction (PCR) from the DNA sample and serum leptin levels were measured by Enzyme-Linked Immuno Sorbent Assay. RESULTS: A total of 159 participants were included (non-obese, n=103; overweight/obese, n=56). Leptin levels were 15.14±12.3 ng/mL in the non-obese group and 26.13±19.0 ng/mL in the overweight/obese group (p≤0.001). The allelic frequencies of the Q and R alleles of the LEPR gene in the studied subjects were as follows: non-obese, Q=0.56, R=0.44; overweight/obese, Q=0.62, R=0.38. The relative risk for the Q/Q genotype was 1.18 (Cl 0.53-2.34), for Q/R was 1.14 (Cl 0.59-2.18) and for R/R was 0.59 (Cl 0.23-1.50). CONCLUSIONS: This study shows that leptin levels are associated with overweight/obesity in Mexican young adults, but this is not related to the presence of the Q223R polymorphism in the LEPR gene, so the underlying mechanisms for a possible disturbance in leptin signaling in obese Mexican young adults await further studies.

Utilidad de la resonancia magnética en el diagnóstico del stroke agudo / Usefulness of magnetic resonance imaging in the diagnosis of acute stroke

Resumen El ataque cerebrovascular (ACV) es la primera causa de discapacidad y la tercera causa de muerte en la Argentina y en el mundo. La etiología del stroke es isquémica en su mayoría (más del 80% de los casos), siendo las causas más frecuentes las lesiones isquémicas de pequeños vasos de tipo lacunar y las tromboembólicas debido a ateroesclerosis de grandes arterias o cardioembolia. Las secuencias utilizadas en nuestro protocolo de estudio incluyen DWI, FLAIR, angio-RM 3D-TOF, SWI y FSE-T1 (tiempo aproximado de exploración de 13 minutos). Pueden observarse diferentes hallazgos en cada una de estas secuencias que son orientativos para determinar la etiología subyacente y estimar el tiempo de evolución de la lesión. En la actualidad, la trombectomía mecánica se ha convertido en el tratamiento de elección en pacientes seleccionados con accidente cerebral isquémico agudo. La transformación hemorrágica es la complicación más temida luego de la terapia de reperfusión intraarterial. La técnica de difusión de la resonancia magnética (RM) posee una mayor sensibilidad para detectar lesiones isquémicas, permite sospechar la etiología según el patrón lesional y aporta información valiosa para la selección de los pacientes candidatos a la reperfusión arterial.

Abstract Stroke or cerebrovascular attack (CVA) is the first cause of disability and the third cause of death in Argentina and in the world. The etiology of strokes is mostly ischemic (more than 80% of cases), with the most frequent causes being lacunar-type ischemic lesions of small vessels and thromboembolic lesions due to atherosclerosis of large arteries or cardioembolism. The sequences used in our study protocol include DWI, FLAIR, angio-RM 3D-TOF, SWI, and FSE-T1 (approximate scan time of 13 minutes). Different findings can be observed in each of these sequences that are indicative to determine the underlying etiology and estimate the time of evolution of the lesion. Currently, mechanical thrombectomy has become the treatment of choice in selected patients with acute ischemic stroke. Hemorrhagic transformation is the most feared complication after intra-arterial reperfusion therapy. The diffusion magnetic resonance technique is more sensitive for detecting ischemic lesions, allows one to suspect the etiology based on the lesion pattern, and provides valuable information for the selection of patients who are candidates for arterial reperfusion.

Diferenciación de la patología tumoral musculoesquelética benigna y maligna utilizando la técnica de difusión con resonancia magnética / Differentiation of benign and malignant musculoskeletal tumor pathology using the diffusion technique with magnetic resonance imaging

Resumen Introducción: La imagen ponderada en difusión es una técnica de imagen funcional que aporta información complementaria a las secuencias convencionales de resonancia magnética. El coeficiente de difusión aparente (CDA) se valora junto con la secuencia de difusión, calculando el logaritmo negativo de la proporción de intensidades de dos conjuntos de imágenes, lo que permite el análisis cuantitativo de la restricción a la difusión. Objetivo: Determinar si existe una diferencia significativa entre los valores de CDA de las lesiones musculoesqueléticas benignas y malignas, correlacionando los resultados con los hallazgos histológicos. Método: Estudio prospectivo, observacional y descriptivo. Se incluyeron en el trabajo pacientes con sospecha de lesiones tumorales del sistema musculoesquelético de cualquier edad y sexo, sin antecedentes de radioterapia previa o cirugía, evaluados con resonancia magnética y con posterior biopsia o cirugía. Resultados: Se incluyeron 170 pacientes, de los cuales 80 (44 benignos) eran hombres y 90 (43 benignos) eran mujeres. El total fue de 87 lesiones benignas y 83 lesiones malignas, con una media de CDA de 1,44 ± 0,55 × 10−3 mm2/s y de 0,96 ± 0,4 × 10−3 mm2/s, respectivamente, con una diferencia estadísticamente significativa (p < 0,001; 6,335; 168). Conclusiones: Los valores de difusión, y particularmente el CDA, han aportado información adicional en la caracterización de los tumores benignos y malignos, con diferencia significativa, estableciendo valores altos de CDA para los tumores benignos.

Abstract Introduction: Diffusion-weighted imaging is a functional imaging technique that provides complementary information to conventional magnetic resonance imaging sequences. The apparent diffusion coefficient (ADC) is evaluated together with the diffusion sequence, calculating the negative logarithm of the intensity ratio of two image sets, allowing the quantitative analysis of the diffusion. Objective: To determine if there is a statistical significance between the ADC values of benign and malignant musculoskeletal lesions, correlating the results with the histological findings. Method: Prospective, observational and descriptive study. Patients with suspected tumoral lesions of the musculoskeletal system of any age and sex, with no history of prior radiation therapy or surgery, evaluated with resonance with subsequent biopsy or surgery. Results: This study included 170 patients. Male patients were 80 (44 benign), and female patients were 90 (43 benign). The total was 87 benign lesions and 83 malignant lesions, with a mean ADC of 1.44 ± 0.55 × 10−3 mm2/s and 0.96 ± 0.4 × 10−3 mm2/s respectively, with a statistical significance (p < 0.001; 6.335; 168). Conclusions: Diffusion and, in particular, ADC values have provided additional information in the characterization of benign and malignant tumors, with a statistical significance, establishing high ADC values for benign tumors.

Microeliminação da hepatite C na população carcerária: realmente possível? / Micro-elimination of hepatitis c in the incarcerated population: is it really possible?

ABSTRACT According to the World Health Organization, 71 million people live with chronic hepatitis C. The treatment of this disease requires assistance from specialized physicians and a highly complex health care system. The prison population has been recognized as being at a high risk of acquiring confinement-related infections, including viral hepatitis. Hepatitis C virus (HCV) infection is a primary cause of death owing to liver disease among liberty-deprived individuals. Generally, prisons do not have adequate isolation wards for persons with communicable diseases, and overcrowding is a risk factor for this population. Besides prison overcrowding, violence, poor sanitary conditions, low socioeconomic status, social isolation, and emotional instability are factors that can lead detainees to adopt unhealthy habits that make them more susceptible to infections, including HCV, and complicate effective treatment. The Criminal Execution Law 7, 210 of July 11, 1984, in Article 14, grants preventive and curative medical, dental, and pharmacological healthcare to detainees. However, adequate hepatitis C treatment is rarely provided at prisons owing to social stigma and lack of knowledge on the severity of this condition or because most detainees are unaware of their condition. Given the multiple limitations imposed by the prison system model, implementing measures to treat diseases effectively is challenging. However, it is possible to eliminate hepatitis C in prisons in the long term through the coordinated action of public health institutions and the prison system.

RESUMO De acordo com a Organização Mundial da Saúde, 71 milhões de pessoas vivem com hepatite C crônica. O tratamento dessa doença requer assistência de médicos especializados e um sistema de saúde de alta complexidade. A população carcerária tem sido reconhecida como sendo de alto risco de adquirir infecções relacionadas às condições de confinamento, incluindo hepatites virais. O vírus da hepatite C (VHC) é uma causa primária de morte por doença hepática em pessoas privadas de liberdade. Geralmente, as prisões não possuem locais adequados para isolamento de pessoas com doenças transmissíveis e a superlotação é um fator de risco para essa população. Além da superlotação das prisões, violência, más condições sanitárias, baixo nível socioeconômico, isolamento social e instabilidade emocional são motivos adicionais que induzem os detidos a praticar hábitos não saudáveis, que os tornam mais suscetíveis a certas infecções (incluindo VHC) e complicam o tratamento específico. A Lei de Execução Penal n. 7.210, de 11 de julho de 1984, em seu artigo 14, garante assistência preventiva e curativa à saúde, incluindo assistência médica, farmacêutica e odontológica aos detidos. No entanto, o tratamento adequado da hepatite C é raramente fornecido nas prisões devido estigma social ou falta de conhecimento de sua condição ou porque a maioria dos detidos não tem conhecimento de sua condição. Devido a múltiplas limitações impostas pelo modelo prisional, a implementação de medidas para o tratamento eficaz de doenças é desafiadora. No entanto, é possível eliminar a hepatite C em um ambiente prisional de longa permanência através de ações coordenadas de instituições de saúde pública e o sistema prisional.

Extracerebral Pterional Metastasis from Malignant Meningioma: A Case Report

Anaplastic or malignant meningiomas that are classified as World Health Organization (WHO) grade III account for less than 1% of all meningiomas diagnosed. Despite the aggressive course, distant metastases are a rarity, occurring in only 0.1% to 0.2% of cases. We report the case of a 56-year-old woman who presented with parasagittal benign meningioma that underwent malignant transformation along with metastasis into the right orbitosphenoid region. The clinical, radiological, and histopathological aspects are highlighted, with an emphasis on the natural history of meningiomas.

A label-free electrochemical immunosensor for hepatitis B based on hyaluronic acid-carbon nanotube hybrid film.

An electrochemical immunosensor developed for detection of antibodies to hepatitis B core protein (anti-HBc) is described. Anti-HBc is the earliest serological marker from hepatitis B virus (HBV) infection, remaining all life after contact with virus, being considered the most important marker for uses in screening of blood bank. A nanohybrid surface assembled onto a glassy carbon electrode consisting of amino carbon nanotubes recovered by hyaluronic acid was used as sensing platform to detect the anti-HBc. All the steps of electrode surface modification were characterized by Scanning Electronic Microscopy and extensively evaluated by electrochemical techniques. The electrode response was measured by direct anti-HBc antigen interactions by square wave voltammetry, dispensing uses of label or chemical mediators. Under optimal conditions, the anodic peak current which was proportional to the anti-HBs concentration. The immunosensor response was linear toward anti-HBc in concentrations up to 6 ng mL(-1), with a detection limit of 0.03 ng mL(-1). The linear range achieved was according to clinical level, indicating the immunosensor as promising tool for use as a criterion for blood bag disposal. The enhancement of the hyaluronic acid by carbon nanotube promoted an increase of charge electron transfer, besides a stable platform for HBc.

Characterization of electrocorticographic, electromyographic and electrocardiographic recordings after the use of caffeine in Wistar rats / Caracterização dos registros eletrocorticográficos, eletromiográficos e eletrocardiográficos após uso de cafeína em ratos Wistar

ABSTRACT Objective: To describe electrocorticographic, electromyographic and electrocardiographic profiles to report the electrophysiological effects of caffeine in Wistar rats. Methods: Male adult Wistar rats weighing 230g to 250g were used. Rats were allocated to one of two groups, as follows: Group 1, Control, intraperitoneal injection of 0.9% saline solution (n=27); and Group 2, treated with intraperitoneal injection of caffeine (50mg/kg; n=27). The rats were submitted to electrocorticographic, electromyographic and electrocardiographic assessment. Results: Brain oscillations (delta, theta, alpha, beta and gamma) in the frequency range up to 40Hz varied after caffeine administration to rats. Powers in delta and theta oscillations ranges were preponderant. The contractile force of the skeletal striated and cardiac muscles increased. Electrocardiogram analysis revealed shorter RR, QRS and QT intervals under the effect of caffeine. Conclusion: In the central nervous system, there was an increase in the delta, theta and alpha amplitude spectrum, which are related to memory encoding and enhanced learning. With regard to skeletal muscle, increased contraction of the gastrocnemius muscle was demonstrated, a clear indication of how caffeine can be used to enhance performance of some physical activities. Electrocardiographic changes observed after caffeine administration are primarily related to increased heart rate and energy consumption.

RESUMO Objetivo: Descrever os perfis eletrocorticográficos, eletromiográficos e eletrocardiográficos para relatar os efeitos eletrofisiológicos da cafeína em ratos Wistar. Métodos: Foram utilizados ratos Wistar, machos, adultos, pesando de 230g a 250g. Os animais foram divididos nos seguintes grupos: Grupo 1, Controle com solução fisiológica 0,9% por via intraperitoneal (n=27), e Grupo 2, Tratado com Cafeína (50mg/kg intraperitoneal; n=27). Foram realizadas avaliações por eletrocorticograma, eletromiograma e eletrocardiograma. Resultados: Houve variações nas oscilações cerebrais (delta, teta, alfa, beta e gama) na faixa de frequência de até 40Hz após a aplicação de cafeína em ratos. Observou-se que as potências nas faixas das oscilações delta e teta foram preponderantes. A força de contração nos músculos estriado esquelético e cardíaco aumentou. A avaliação do eletrocardiograma demonstrou que a duração dos intervalos RR, QRS e QT foram menores na presença da cafeína. Conclusão: No sistema nervoso central, houve aumento dos espectros de amplitude delta, teta e alfa, que auxiliam na codificação das memórias e estão relacionados à melhora do aprendizado. Em relação à musculatura esquelética, demonstrou-se aumento da contração do músculo gastrocnêmio, uma clara indicação de como a cafeína pode ser usada para aumentar o desempenho em algumas atividades físicas. As alterações eletrocardiográficas observadas após a administração de cafeína estiveram relacionadas principalmente ao aumento da frequência cardíaca e do consumo de energia.

Hemifacial Spasm Associated with Chiari Type I Malformation: Surgical Considerations and Case Report

Hemifacial spasm (HS) is a movement disorder characterized by paroxysmal and irregular contractions of the muscles innervated by the facial nerve. Chiari malformation type I (CM I) is a congenital disease characterized by caudal migration of the cerebellar tonsils, and surgical decompression of foramen magnum structures has been used for treatment. The association of HS with CM I is rare, and its pathophysiology and therapeutics are speculative. There are only a few cases reported in the literature concerning this association. The decompression of the posterior fossa for the treatment of CM I has been reported to relieve the symptoms of HS, suggesting a relation between these diseases. However, the possible complications of posterior fossa surgery cannot be underrated. We report the case of a 66-year-old patient, in ambulatory follow-up due to right HS, no longer responding to botulinum toxin treatment. Magnetic resonance imaging (MRI) of the skull revealed compression of the facial nerve and CM I. The patient underwent surgery for HS by neurovascular microdecompression of the facial nerve via right lateral suboccipital craniectomy, but presented significant clinical worsening in the postoperative period even though the cerebellum edema related to surgical manipulation was mild. Due to the clinical worsening, the patient underwent a median suboccipital craniectomy with decompression of the foramenmagnum structures. After this second surgery, the patient had progressive improvement and was discharged from the hospital for ambulatory care.

Rupturas agudas de ligamento cruzado anterior. ¿Existe la cicatrización espontánea? / Anterior cruciate ligament acute ruptures. Is there spontaneous healing?

OBJETIVOS: Identificar pacientes que, con diagnóstico de ruptura aguda y completa del LCA, cicatrizaron espontáneamente; y si esta curación tiene relación con la edad, sexo, tipo de ruptura, tiempo de reposo y mecanismos del trauma. MATERIALES Y MÉTODOS: Se evaluaron 30 pacientes con ruptura aguda completa del LCA mediante diagnóstico clínico e imagenológico con resonancia magnética nuclear (RMN). Se utilizó para valoración subjetiva test de Lysholm e IKDC 2000. RESULTADOS: Todos los pacientes mejoraron de la primera a la segunda consulta, con resultados: Lachman (p<0.0406), pivot shift (p=0.071) y cajón anterior (p<0.001). En la segunda RMN de control, se observó el LCA con signos de cicatrización en la totalidad de los pacientes. Podría inferirse, con un seguimiento promedio de 12 meses para hombres (IC95% 6-17) y de 13 meses para las mujeres (IC95% 31max), una recuperación clínica prácticamente completa, así como también que la cicatrización se produciría independientemente de variables como la edad, sexo o tratamiento específico (p=0.795 y p=0.841). CONCLUSIÓN: A pesar de la limitación del tamaño del presente estudio, los objetivos planteados fueron alcanzados. Existiría la cicatrización espontánea del LCA y la misma no estaría asociada a la edad, sexo, ni a tratamientos específicos de fisioterapia o al uso de inmovilizadores; aunque sí, al reposo durante los primeros 3 meses post lesión. Tipo de estudio: Retrospectivo. Nivel de evidencia: IV.

OBJECTIVES: To identify patients who, with a diagnosis of acute and complete ACL rupture, healed spontaneously, and determine whether such healing is related to age, sex, type of rupture, resting time, and mechanisms of trauma. MATERIALS AND METHODS: Thirty patients with complete acute ACL rupture were evaluated by clinical diagnosis and Magnetic Resonance Image (MRI). Both Lysholm test and IKDC 2000 were used for subjective evaluation. RESULTS: All patients improved from the first to the second consultation, with results: Lachman (p <0.0406), pivot shift (p = 0.071), and anterior drawer (p <0.001). In the second control MRI, ACL with signs of healing in all patients were observed. With an average follow-up of 12 months for men (95% CI 6-17) and 13 months for women (95% CI 31max), a practically complete clinical recovery could be inferred, as well as healing taking place independently of variables such as age, sex, or specific treatment (p = 0.795 and p = 0.841). CONCLUSION: Despite the size limitation for the present study, the objectives set were achieved. There would be spontaneous ACL healing associated with a 3-month-post-injury resting time, but dissociated from age, sex, specific physiotherapy treatments, or the use of immobilizers. Type of study: Retrospective. Level of evidence: IV.