Pyrazinamide susceptibility testing in Mycobacterium tuberculosis using the fast resazurin microtiter assay plate.

SETTING: Department of Clinical Analysis and Biomedicine, State University of Maringa, Maringa, PR, Brazil. OBJECTIVE: To evaluate the performance of the resazurin microtiter assay (REMA) plate at pH 5.5 in detecting Mycobacterium tuberculosis susceptibility to pyrazinamide (PZA). DESIGN: The minimal inhibitory concentration (MIC) of PZA in M. tuberculosis H37Rv and M. bovis AN5 reference strains and in 34 clinical M. tuberculosis isolates (26 PZA-susceptible and eight PZA-resistant) was determined using REMA at pH 5.5 and compared to REMA at pH 6.0. RESULTS: REMA at pH 5.5 was helpful in discriminating PZA-susceptible from resistant M. tuberculosis isolates when â©¿50 µg/ml PZA was considered as the cut-off for PZA susceptibility. Furthermore, it provided results in 8 days. However, two PZA-resistant isolates failed to grow at pH 5.5. CONCLUSION: As the REMA method is rapid, inexpensive, easy to perform and read, it would be of great usefulness in low-income countries for detecting PZA-resistant M. tuberculosis. REMA at pH 5.6-5.9 should be evaluated on an extended panel of clinical M. tuberculosis isolates with a greater range of MIC values in different laboratories for a better understanding of its utility in differentiating PZA-resistant from PZA-susceptible isolates.

A comprehensive clinical and genetic study of a large Mexican population with spinocerebellar ataxia type 7.

Spinocerebellar ataxia type 7 (SCA7) is an inherited neurodegenerative disorder characterized by progressive cerebellar ataxia associated with macular degeneration. We recently described one of the largest series of patients with SCA7 that originated from a founder effect in a Mexican population, which allowed us to perform herein the first comprehensive clinical, neurophysiological, and genetic characterization of Mexican patients with SCA7. In this study, 50 patients, categorized into adult or early phenotype, were clinically assessed using standard neurological exams and genotyped using fluorescent PCR and capillary electrophoresis. Patients with SCA7 exhibited the classical phenotype of the disease characterized by cerebellar ataxia and visual loss; however, we reported, for the first time, frontal-executive disorders and altered sensory-motor peripheral neuropathy in these patients. Semiquantitative analysis of ataxia-associated symptoms was performed using Scale for the Assessment and Rating of Ataxia (SARA) and the Brief Ataxia Rating Scale (BARS) scores, while extracerebellar features were measured employing the Inventory of Non-ataxia Symptoms (INAS) scale. Ataxia rating scales confirmed the critical role size of cytosine-adenine-guanine (CAG) repeat size on age at onset and disease severity, while analysis of CAG repeat instability showed that paternal rather than maternal transmission led to greater instability.

Analysis of CAG repeats in five SCA loci in Mexican population: epidemiological evidence of a SCA7 founder effect.

Spinocerebellar ataxias (SCA) are a heterogeneous group of neurodegenerative disorders. CAG (cytosine-adenine-guanine) trinucleotide repeat expansions in the causative genes have been identified as the cause of different SCA. In this study, we simultaneously genotyped SCA1, SCA2, SCA3, SCA6, and SCA7 applying a fluorescent multiplex polymerase chain reaction assay. We analyzed 10 families with SCA (64 patients) from five different communities of Veracruz, a Mexican southeastern state, and identified 55 patients for SCA7 and 9 for SCA2, but none for SCA1, SCA3, or SCA6. To our knowledge, this sample represents one of the largest series of SCA7 cases reported worldwide. Genotyping of 300 healthy individuals from Mexican population and compiled data from different ethnicities showed discordant results concerning the hypothesis that SCA disease alleles arise by expansion of large normal alleles.

Piracetam-induced changes on the brainstem auditory response in anesthetized juvenile rhesus monkeys (Macaca mulatta). Report of two clinical cases.

BACKGROUND: We describe two clinical cases and examine the effects of piracetam on the brainstem auditory response in infantile female rhesus monkeys (Macaca mulatta). RESULTS: We found that the interwave intervals show a greater reduction in a 3-year-old rhesus monkey compared to a 1-year-old rhesus monkey. DISCUSSION: In this report, we discuss the significance of these observations.

The selective inhibition of the D1 dopamine receptor results in an increase of metabolized dopamine in the rat striatum.

Our aim was to study the specific role of the postsynaptic D(1) receptors on dopaminergic response and analyze the metabolized dopamine (DA) in the rat striatum. We used male Wistar rats to evaluate the effects of different doses of a D(1) agonist (SKF-38393) and a D(1) antagonist (SCH-23390), and their co-administration. The levels of DA and L-3, 4-dihydroxyphenylacetic acid (DOPAC) were measured using high performance liquid chromatography. The systemic injection of SKF-38393 alone at 1, 5 and 10 mg/kg did not alter the DA and DOPAC levels or the DOPAC/DA ratio. In contrast, injection of SCH-23390 alone at 0.25, 0.5 and 1 mg/kg significantly increased the DA and DOPAC levels, as well as the DOPAC/DA ratio, compared with the respective control groups. The co-administration of SCH-23390+SKF-38393 did not alter the DA or DOPAC levels, but it did significantly inhibit the SCH-23390-induced increase of the DA and DOPAC levels. The SCH-23390+SKF-38393 and the SCH-23390-only groups showed an increase in the DOPAC/DA ratio. The co-administration of SCH-23390+PARGYLINE significantly decreased the DOPAC levels and the DOPAC/DA ratio compared with the control and SCH-23390 groups. Taken together, our results showed that selective inhibition with SCH-23390 produced an increase in metabolized DA via striatal monoamine oxidase. These findings also contribute to the understanding of the role of postsynaptic D(1) receptors in the long-loop negative feedback system in the rat striatum.

Burden of disease related to hepatitis C and hepatitis B in Spain: a methodological challenge of an unfolding health problem.

Most previous studies of burden of disease (BoD) in the area of transmissible diseases have assessed the burden of hepatitis C and B without including the end stages of the disease and using an incident approach. We aimed to assess the disability-adjusted life years (DALYs) related to hepatitis C and B in Spain in 2006 taking into account related cirrhosis and liver cancer. A prevalence approach was used to estimate current years lived with disability (YLD) because of viral hepatitis contracted years/decades before. We added years of life lost (YLL) to obtain DALYs. Around 76,000 DALYs were attributed to hepatitis C virus (HCV) and 15,323 to hepatitis B virus (HBV) when calculated without applying social values. Applying the discount rate and age-weighting used in the Global Burden Disease study, the BoD nearly halved. In any case, the burden related to hepatitis C including long-term outputs becomes the leading cause of DALYs among transmissible diseases in Spain. The mortality component (YLL) represents more than 90% of the BoD in both HCV and HBV. The findings emphasize the need to provide good surveillance systems not only concerning acute viral hepatitis, but also chronic and end-stage consequences to allow a reliable assessment of the prevention and public health control policies.

A dot-ELISA using a partially purified cathepsin-L-like protein fraction from Taenia solium cysticerci, for the diagnosis of human neurocysticercosis.

Human neurocysticercosis (NCC), caused by the cestode Taenia solium, is responsible for a significant amount of neurological morbidity and epilepsy in developing countries. The disease remains highly endemic in many areas, despite several efforts and interventions to control it. A simple, cheap and fast diagnostic assay that is suitable for use in field conditions is highly desired. In immunodiagnostics based on western immunoblots or standard ELISA, a cathepsin-L-like protein purified from the cysticercus fluid has previously performed well as an antigen. In a recent study in Peru, the same 53/25-kDa antigen was therefore used in the development of a dot-ELISA that could be employed for mass screenings under field conditions. The assay was standardized and tested not only against sera from a large group of NCC cases but also against sera from patients with other common parasitic infections, so that sensitivity and specificity could be assessed. For NCC, the assay gave better sensitivity in the detection of individuals with extraparenchymal cysts (94·4%-100%) or multiple parenchymal cysts (74·6%-80·0%) than in the detection of individuals with single parenchymal cysts (29·4%-45·1%). The assay also showed a high specificity for NCC (99·0%-100%), with a very low level of cross-reactivity with other parasitic infections. The dot-ELISA developed in this study is a highly specific, simple, cheap and rapid test for NCC that could be used under field conditions, even in the low-resource settings that are common in developing countries.

[Paradigm of negative feedback via long-loop in the striatal dopamine release modulation in the rat]. / Paradigma de retroalimentacion negativa via circuito largo en la modulacion de la liberacion de dopamina en el estriado dorsal de la rata.

INTRODUCTION: The basal ganglia include the striatum, globus pallidus, the substantia nigra pars compacta and pars reticulata. The striatum receives afferent input from the substantia nigra pars compacta. The principal neurons of the striatum are medium spiny neurons, that express high levels of D1 and D2 receptors. AIMS: This review deals about the aspects underlying to the negative feedback via long-loop in the striatal dopamine release modulation in the rat. Also, the motor function in dopamine receptor knock-out mice is discussed. DEVELOPMENT AND CONCLUSIONS: The intrastriatal infusion and systemic injection of dopamine receptor agonists and antagonists may regulate the striatal dopamine release and induce changes in motor function. Disruption of the D1 and D2 gene shown that the motor function is controlled by D1 and D2 receptors. The study of the long-loop negative feedback may contribute to our understanding in the physiology and dysfunction of basal ganglia.

Sensitivity analysis of surface runoff generation in urban flood forecasting.

Reliable flood forecasting requires hydraulic models capable to estimate pluvial flooding fast enough in order to enable successful operational responses. Increased computational speed can be achieved by using a 1D/1D model, since 2D models are too computationally demanding. Further changes can be made by simplifying 1D network models, removing and by changing some secondary elements. The Urban Water Research Group (UWRG) of Imperial College London developed a tool that automatically analyses, quantifies and generates 1D overland flow network. The overland flow network features (ponds and flow pathways) generated by this methodology are dependent on the number of sewer network manholes and sewer inlets, as some of the overland flow pathways start at manholes (or sewer inlets) locations. Thus, if a simplified version of the sewer network has less manholes (or sewer inlets) than the original one, the overland flow network will be consequently different. This paper compares different overland flow networks generated with different levels of sewer network skeletonisation. Sensitivity analysis is carried out in one catchment area in Coimbra, Portugal, in order to evaluate overland flow network characteristics.

[Is cochlear processing involved in language disorders?]. / El procesamiento coclear está involucrado en los problemas de lenguaje?

INTRODUCTION: Otoacoustic emissions are evidence of the existence of an active process in the cochlea, and the motility of the outer hair cells means that they can change the cochlear mechanical response. We believe that incorrect processing of the sounds of language in the cochlea can result in impaired language processes. SUBJECTS AND METHODS: Data were collected from the patient record; neurological, visual and auditory examination; Weschler intelligence scale; initial language test (ILT); brainstem auditory evoked potentials (BAEPs) and transient otoacoustic emissions. The results of the ILT were used to form three groups: controls, pathological and pathological with normal ILT. RESULTS: All the children presented a response at 20 dB by means of the BAEPs. In the transient otoacoustic emissions, Student's t test was conducted between the right and the left ear for total reproducibility and reproducibility at different band frequencies within each group. No significant differences were observed. The same test was carried out between groups (controls versus pathological, controls versus pathological with normal ILT, and pathological versus pathological with normal ILT) in the right and left ears; no significant differences were found in the total reproducibility for the two ears. No significant differences were found in the reproducibility at different frequency bands for the left ear, but some were found in the case of the right ear. CONCLUSIONS: Laterality from the periphery exists for language processing and if this process fails to perform correctly, due to malfunctioning of the outer hair cells, language may be affected.

Indications for and results of liver retransplantation.

Liver retransplantation (LReTx) is the therapeutic option for the irreversible failure of a hepatic graft. Our aim was to evaluate the rate of and indications for LReTx and actuarial patient survivals. Among 1260 LTx were 79 LReTx (6.3%). During the first LTx, there were no apparent differences between patients who did or did not required LReTx. The most frequent reasons were hepatic artery thrombosis (31.6%), recurrence of the VHC cirrhosis (30.4%), and primary graft failure (21.5%). The actuarial survivals at 1 and 5 years were 83% and 69% among those without LReTx versus 71% and 61% among early LReTx, and 64% and 34% among late LReTx (P < .001). Although there exists high morbidity and mortality with LReTx, it seems that this therapeutic alternative continues to be valid for patients with early hepatic loss, but not when the graft loss was late. It becomes necessary to define the minimal acceptable results that patient can benefit from LReTx.

[Anatomic and topographic models of the cerebral areas that activates during the linguistic functions]. / Modelos anatomotopográficos de las áreas cerebrales que se activan durante la función lingüística.

AIM: A brief revision was performed in order to develop a topographic model of cerebral activation during silent reading, syllable's repetition and emotional prosody, based in recent neuroimaging studies. DEVELOPMENT: It has been reported that the words are analyzed in both occipital hemispheres during silent reading, after they are 'written' in the right temporal cortex while the integration of the semantic and phonologic processes are integrated on different left temporal areas and also in the left frontal lower part. The understanding is achieved in the left-middle temporal cortex. In the other hand, activation during articulatory movements is carried out in the left supratemporal gyrus and the left motor and premotor cortex, the left putamen and part of both hemispheres of the cerebellum. Finally, recognition of the emotional prosody occurs in three stages: obtaining of the acoustic information in some areas of the right temporal lobe, representation of acoustic sequences in the right posterio-superior temporal area, and an evaluation of the emotional prosody in the lower frontal bilateral cortex, with the involvement of the basal ganglia in the emotional expression. CONCLUSIONS: The location and synchrony of the areas that activate during the language processing is lateralized toward the left hemisphere and it involves cortical and subcortical areas, except for the emotional prosody. The understanding of the language processes will open the field for to take advantage of the plastic mechanisms for the speech therapy and rehabilitation.

[Evaluation of the motor behavior in rats with cortical ablation]. / Caracterizacion de la conducta motora en ratas con ablacion cortical.

INTRODUCTION: The cortical ablation has been used as an experimental model in order to study the basic mechanisms of functional recovery. However, there is not data concerning to the injury effects on the motor and somatosensorial behavioral manifestations that allow us to categorize such sequels as a hemiplegic model. MATERIALS AND METHODS: We used 35 male Wistar rats (280-300 g) allocated in two groups: control (n = 17) and brain injured by cortical ablation (n = 18). Previously trained, basal recordings of the footprint and motor and somatosensorial assessment were performed in the rats before surgery. The behavioral tests were performed again 6 hours after surgery and the spontaneous ambulatory activity was also evaluated. RESULTS AND CONCLUSIONS: It was observed a decrease in the stride's length and an increase in the stride's angle and in the motor deficit, while the somatosensorial assessment and spontaneous ambulatory activity were not affected. These findings are discussed in function of the motor features of the hemiparetic sequels in humans.

Propuesta metodológica para el análisis del flujo informacional en las organizaciones / Methodological proposal for the analysis of information flow chart in organizations

Ante la necesidad de desarrollar una herramienta para diagnosticar y auditar los flujogramas informacionales en las organizaciones que asumen la información como un activo intangible de alto valor, se propone una metodología para su análisis con un enfoque sistémico y sobre la base de un enfoque estratégico gerencial. Se exponen las tareas y salidas previstas en cada paso, sus tecnologías, recursos, y el lugar del factor humano, desde la perspectiva del enfoque de proceso. Mediante un software diseñado para el estudio de las redes y grafos, se crean las bases de datos de cada subsistema y se muestra su interrelación informacional. El estudio de un caso ilustra la propuesta realizada.

Facing the need of developing a tool to diagnose and audit informational flow charts in organizations that understand information as an intangible asset of high value, it is proposed a systemic methodology of analysis, based on a managerial strategic approach. The tasks and solutions forseen for each step, as well as their technologies, resources, and the place of the human factor, are exposed from the perspective of the process approach. By means of a software designed for the study of graphs and networks, the databases of every subsystem are created and their informational interrelation is shown. The study of a case illustrates the proposal.

Reconstrucción de lesiones de extremidad inferior con Colgajo de Arteria Sural Superficial, experiencia de 10 años / Reconstruction of lower extremity lesions with superficial sural artery flap: a ten-year experience

La cobertura de heridas complejas en extremidades inferiores es un desafío de difícil manejo. Se realizó un estudio retrospectivo, analizando el resultado y las complicaciones en el uso del colgajo sural a pedículo distal para cobertura de defectos de extremidad inferior. Material y Método: Revisión de fichas clínicas de todos los pacientes sometidos a colgajo sural en los Hospitales Militar y Trabajador de Santiago entre los años 1995 y 2005, analizando características epidemiológicas, técnica quirúrgica y complicaciones del procedimiento. Resultados: Colgajos surales totales: 40 casos. Etiología de lesión: Fracturas: 33 casos (82,5%), heridas complejas (infectadas, inestables) 4 casos (10%), desforrramiento: 2 casos (5%) y quemadura: 1 caso (2,5%). En 20 casos no hubo complicación, y dentro de las complicaciones se encontraron necrosis parcial: 8 casos (20%), infección: 5 casos (12,5%), epidermolísis: 4 casos (10%) y seroma en 3 casos (7,5%). No se reportaron casos de necrosis total. Conclusión: El colgajo sural a pedículo distal es una alternativa válida de cobertura en lesiones complejas de extremo distal de extremidad inferior, con complicaciones de manejo aceptables, y con buen resultado a largo plazo.

Background: The covering of complex wounds of lower extremities is a difficult challenge. Aim: To analyze the results and complications on the use of sural flaps with distal pedicle for the covering of lower extremity defects. Material and Methods: We reviewed the clinical records of all the patients that had sural flaps between 1995 and 2005 at the Military Hospital and Workers Hospital of Santiago, Chile. We analyzed the epidemiologic characteristics, surgical techniques and complications of the procedure. Results: We found 40 cases of sural flaps. The etiology of the lesions were fractures in 33 cases (82.5%), complex wounds: four cases (10%), skin tearing and muscle laceration in 2 cases (5%) and burns 1 case (2.5%). In 20 cases there were no complications. Eight cases had partial necrosis (20%), five had infections (12.5%), four had epidermolysis and three had a seroma (7.5%). There were no reports of total necrosis. Conclusions: Sural flaps with a distal pedicle are a valid alternative for the covering of complex wounds of the distal portion of lower extremities, with a low rate of complications and good long term results.

Effect of pentobarbital on pH and electrolyte levels after induced seizure in rats.

We studied the effects of high doses of pentobarbital (PB) and carbamazepine (CBZ) on electrolyte levels and pH in an epileptic animal model. Pentobarbital decreased Ca2+ and Na+ levels without pentylenetetrazole (PTZ). After this, Ca2+ and Na+ levels continued to decrease except when CBZ was used, which preserved the Ca2+ levels PTZ may have opposed effects on PB. Our results suggest that PB causes changes in electrolyte levels and pH, but these changes are diminished by CBZ.

Prevalencia de anemia ferropénica en escolares de 1ro a 6to grado de la Escuela Bolivariana Las dos Bocas, Municipio Colina, Estado Falcón: febrero-junio, 2004 / Prevalencia of anemia ferropenica in school of 1ro to 6to grade of the school Bolivarian Las Dos Bocas, Municipality Colina, State Falcon: february-june 2004

La deficiencia de hierro es el problema nutricional más común en el mundo así la anemia ferropénica es la enfermedad hematológica más frecuente de la infancia, constituye una de las principales causas de morbilidad y mortalidad en el mundo entero. Con el propósito de determinar la prevalencia de anemia ferropénica en escolares de 1ro a 6to grado de la Escuela Bolivariana Las Dos Bocas, Municipio Colonia del Estado Falcón, en el lapso comprendido entre febrero-junio 2004; se realizó un estudio descriptivo, diagnóstico y transversal, con muestreo probabilístico simple, que incluyó 24 escolares se determinó: hemoglobina, hematocrito, índices hematimétricos por técnica semi-automatizada y niveles séricos de hierro y ferritina, a través del test inmunoenzimático ELISA. Los valores de referencia fueron los establecidos como normales por la Organización Mundial de la Salud. El 58,3 por ciento de los escolares presentó niveles de Hb y Hto bajos. El 71,4 por ciento de los escolares anémicos presentó índices hematimétricos bajos. El 25 por ciento mostró niveles de hierro debajo de lo normal y el 41,6 por ciento presentó niveles bajos de ferritina. La prevalencia de anemia ferropénica obtenida fue de 25 por ciento ferropenía sin anemia 16,6 por ciento . El valor promedio de Hb encontrado en escolares sin déficit de hierro fue 11,75 g/dl. Se concluye que la prevalencia de anemia ferropénica es alta en el Estado Falcón. Se hace nesesario la determinación de hierro sérico y ferritina sérica para el diagnóstico específico de la anemia por déficit de hierro.

Serotonin and 5-hydroxy-indole-acetic acid contents in dorsal raphe and suprachiasmatic nuclei in normal, malnourished and rehabilitated rats under 24 h of sleep deprivation.

It has been discussed that serotonin (5-HT) could be involved in the effects of sleep deprivation (SD) and/or malnutrition (M) on the sleep-wake cycle. The aim of this work was to study the effects of the M, SD and its interaction on 5-HT and 5-hydroxy-indole-acetic acid (5-HIAA) contents in the dorsal raphe (DR) and the suprachiasmatic nuclei (SCN), two sleep-wake cycle regulators. Forty-eight puppets rats were obtained from mothers fed with low or normal casein diet. They were allocated in 3 groups (n=16 each): prenatal/postnatal casein malnutrition (6/6%), prenatal casein malnutrition/nutritional casein rehabilitation (6/25%) and prenatal/postnatal casein well-nourished state (25/25%). When rats were 60 days old, 24 animals were exposed to sleep deprivation by means of forced locomotion during 24 h. The remaining 24 were kept under normal conditions of sleep-wake cycle. Then, all animals were sacrificed by decapitation. DR and SCN were dissected and processed to determine the 5-HT and 5-HIAA contents by means of HPLC. It was observed that 6/6% rats showed a 5-HT increase (DR p<0.011; SCN p<0.019) as well as in SD (DR p<0.0008; SCN p<0.0009) with respect to 25/25% rats. No differences were found in 6/25% rats. Therefore, 5-HIAA decreased significantly in both nuclei in all the groups, notably in M+SD animals (DR p<0.001; SCN p<0.001). We conclude that the sleep-wake cycle disruptions produced by chronic M and SD are mediated in part by a synergistic effect on 5-HT in the DR-SCN pathway, perhaps due to a delay in the development of such brain structures.