Understanding electrical and chemical transmission in the brain.

The histochemical Falck-Hillarp method for the localization of dopamine (DA), noradrenaline (NA) and serotonin in the central nervous system (CNS) of rodents was introduced in the 1960s. It supported the existence of chemical neurotransmission in the CNS. The monoamine neurons in the lower brain stem formed monosynaptic ascending systems to the telencephalon and diencephalon and monoamine descending systems to the entire spinal cord. The monoamines were early on suggested to operate via synaptic chemical transmission in the CNS. This chemical transmission reduced the impact of electrical transmission. In 1969 and the 1970s indications were obtained that important modes of chemical monoamine communication in the CNS also took place through the extra-synaptic fluid, the extracellular fluid, and long-distance communication in the cerebrospinal fluid involving diffusion and flow of transmitters like DA, NA and serotonin. In 1986, this type of transmission was named volume transmission (VT) by Agnati and Fuxe and their colleagues, also characterized by transmitter varicosity and receptor mismatches. The short and long-distance VT pathways were characterized by volume fraction, tortuosity and clearance. Electrical transmission also exists in the mammalian CNS, but chemical transmission is in dominance. One electrical mode is represented by electrical synapses formed by gap junctions which represent low resistant passages between nerve cells. It allows for a more rapid passage of action potentials between nerve cells compared to chemical transmission. The second mode is based on the ability of synaptic currents to generate electrical fields to modulate chemical transmission. One aim is to understand how chemical transmission can be integrated with electrical transmission and how putative (aquaporin water channel, dopamine D2R and adenosine A2AR) complexes in astrocytes can significancy participate in the clearance of waste products from the glymphatic system. VT may also help accomplish the operation of the acupuncture meridians essential for Chinese medicine in view of the indicated existence of extracellular VT pathways.

CYP46A1-mediated cholesterol turnover induces sex-specific changes in cognition and counteracts memory loss in ovariectomized mice.

The brain-specific enzyme CYP46A1 controls cholesterol turnover by converting cholesterol into 24S-hydroxycholesterol (24OH). Dysregulation of brain cholesterol turnover and reduced CYP46A1 levels are observed in Alzheimer's disease (AD). In this study, we report that CYP46A1 overexpression in aged female mice leads to enhanced estrogen signaling in the hippocampus and improved cognitive functions. In contrast, age-matched CYP46A1 overexpressing males show anxiety-like behavior, worsened memory, and elevated levels of 5α-dihydrotestosterone in the hippocampus. We report that, in neurons, 24OH contributes to these divergent effects by activating sex hormone signaling, including estrogen receptors. CYP46A1 overexpression in female mice protects from memory impairments induced by ovariectomy while having no effects in gonadectomized males. Last, we measured cerebrospinal fluid levels of 24OH in a clinical cohort of patients with AD and found that 24OH negatively correlates with neurodegeneration markers only in women. We suggest that CYP46A1 activation is a valuable pharmacological target for enhancing estrogen signaling in women at risk of developing neurodegenerative diseases.

Prevalence and Clinical Factors Associated With Pes Planus Among Children and Adults: A Population-Based Synthesis and Systematic Review.

Estimates of pes planus ("flatfoot") prevalence vary considerably across studies. Moreover, there is uncertainty over which factors are associated with the pes planus prevalence. We aimed to systematically review the prevalence and clinical factors associated with flatfoot among children and adults. We searched Web of Science, PubMed/MEDLINE, and Google Scholar databases reporting population-based flatfoot prevalence. Two reviewers independently extracted the data and assessed the qualities of the studies. Subgroup analysis was conducted to analyze the associated factors on flatfoot prevalence. Frequencies, odds ratios (OR), and 95% confidence intervals (CI) were performed using descriptive analysis and chi-square test accounting for heterogeneity. Any conflict in the data analysis was discussed by all the reviewers. Twelve studies including 2509 flatfoot cases were analyzed (overall prevalence 15.6%, n = 16,000). The subgroup analysis indicated that male gender (OR = 1.26, 95% CI: 1.15-1.37), age groups 3 to 5 years (OR = 2.02, 95% CI: 1.78-2.30) and 11 to 17 years (OR = 1.91, 95% CI: 1.64-2.22), Asian race (OR = 2.34, 95% CI: 2.10-2.60), and obesity (OR = 2.62, 95% CI: 2.06-3.32) were more associated with flatfoot (p < .001). Conversely, female gender (OR = 0.44, 95% CI: 0.40-0.48) and White race (OR = 0.52, 95% CI: 0.47-0.57) were less associated with flatfoot (p < .001). Our findings may be valuable for clinical/surgical settings, particularly, for those modifiable findings and targeted populations. However, we suggest that future studies estimating flatfoot should consider prospective/multicenter designs using a common screening methods in random samples populations.

Guía de práctica clínica para el diagnóstico y tratamiento de la distrofia muscular de Duchenne. Sociedad Peruana de Neurología. Versión Corta / Clinical Practice Guidelines for diagnosis and treatment of Duchenne muscular dystrophy. Peruvian Neurology Society. Short Version

RESUMEN Objetivo : Elaborar una guía de práctica clínica peruana para el diagnóstico y tratamiento de la Distrofia Muscular de Duchenne y Becker (DMD). Materiales y métodos : Se conformó un grupo elaborador de la guía (GEG) que incluyó médicos especialistas en neurología, neuropediatría, genética y metodología. El GEG formuló ocho preguntas para desarrollar las recomendaciones de la Guía de Práctica Clínica (GPC). Se realizó una búsqueda sistemática en Medline, Scopus y CCRT durante el periodo enero-abril 2021 para responder a las preguntas PICO. La certeza de la evidencia fue evaluada usando la metodología Grading of Recommendations Assessment, Development, and Evaluation (GRADE). Resultados : Las preguntas PICO, se orientaron para explorar el tamizaje, diagnóstico y tratamiento de la DMD. Se formularon 15 recomendaciones (10 fuertes, 5 condicionales) y 11 puntos de buena práctica clínica Conclusión : Se presenta la guía para el diagnóstico y tratamiento de la DMD, elaborada bajo una metodología basada en las evidencias actuales.

ABSTRACT Objective : to provide evidence-based clinical recommendations for the diagnosis and treatment of Duchenne Muscular Dystrophy. Methods : a guideline development group (GEG) was formed that included specialized physicians in the fields of neurology, neuropediatrics, genetics, and methodology. The GEG asked eight clinical questions to be answered by recommendations in this clinical practice guidelines (CPG). We conducted a systematic search and - when deemed relevant - primary studies in Medline, Scopus, and the Cochrane Controlled Register of Trials during 2021 were reviewed. Evidence was selected to answer each of the clinical questions posed. Certainty of the evidence was assessed using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system. In periodic work meetings, the GEG used the GRADE methodology to review the evidence and formulate recommendations, points of good clinical practice, and a diagnosis and treatment flowchart. Results : this CPG addressed eight clinical questions, divided into three topics: screening, diagnosis, and treatment. Based on these questions, fifteen recommendations were formulated (10 strong, 5 conditional) and 11 points for good clinical practice. Conclusion : this paper summarizes the methodology and evidence- based conclusions of the CPG for the diagnosis and treatment of Duchenne muscular dystrophy.

Intranasal delivery of pro-resolving lipid mediators rescues memory and gamma oscillation impairment in AppNL-G-F/NL-G-F mice.

Sustained microglial activation and increased pro-inflammatory signalling cause chronic inflammation and neuronal damage in Alzheimer's disease (AD). Resolution of inflammation follows neutralization of pathogens and is a response to limit damage and promote healing, mediated by pro-resolving lipid mediators (LMs). Since resolution is impaired in AD brains, we decided to test if intranasal administration of pro-resolving LMs in the AppNL-G-F/NL-G-F mouse model for AD could resolve inflammation and ameliorate pathology in the brain. A mixture of the pro-resolving LMs resolvin (Rv) E1, RvD1, RvD2, maresin 1 (MaR1) and neuroprotectin D1 (NPD1) was administered to stimulate their respective receptors. We examined amyloid load, cognition, neuronal network oscillations, glial activation and inflammatory factors. The treatment ameliorated memory deficits accompanied by a restoration of gamma oscillation deficits, together with a dramatic decrease in microglial activation. These findings open potential avenues for therapeutic exploration of pro-resolving LMs in AD, using a non-invasive route.

The urban contrast: A nationwide assessment of avian diversity in Mexican cities.

In this study we focused on urban bird diversity across Mexico, a megadiverse country, with a special focus on the relative role of urban greenspaces and heavily-built sites. We considered a country-wide approach, including 24 different sized Mexican cities. Our aims were to describe the urban bird diversity in focal cities and further assess the relationships between it and the biogeographic region where cities are located, their size, elevation, and annual rainfall. Additionally, we evaluated differences in the functional composition of bird communities in both studied urban scenarios (i.e., urban greenspaces, heavily-built sites). Our results confirm that urban greenspaces are home to a large proportion of species when contrasted with heavily-built sites. While total species richness and species richness of greenspaces were related with the cities' biogeographic region -with higher species richness in the Neotropical region and Transition Zone-, the relationship did not hold true in heavily-built sites. We found that annual rainfall was negatively related to bird richness in heavily-built sites, suggesting that species from arid systems can be more tolerant to urbanization. Regarding the bird functional group assessment, results show a clear differentiation between the functional groups of greenspaces and those of heavily-built sites, with granivores and omnivores associated with the latter and a highly diverse array of functional groups associated with urban greenspaces.

Cambios hematológicos relacionados con componentes del síndrome metabólico en personal de salud con alimentación balanceada / Hematological changes related to metabolic syndrome components in healthpersonnel with a balanced diet

INTRODUCCIÓN: El síndrome metabólico (SM) es un conjunto de trastornos interrelacionados que produce alteraciones en diversos sistemas biológicos. OBJETIVO: El objetivo de este estudio fue evaluar los cambios hematológicos en presencia de síndrome metabólico en personal de salud con alimentación balanceada. Materiales y MÉTODOS: Se realizó un estudio transversal donde se analizó la base de datos del personal de salud que participó del Plan de Prevención de Enfermedades Transmisibles y no Transmisibles del Hospital de Huaycán, Perú. La evaluación del SM se realizó usando los criterios de la Asociación Latinoamericana de Diabetes (ALAD) en los trabajadores que presentaron alimentación balanceada según el cuestionario "FANTÁSTICO". La relación entre los cambios hematológicos y componentes del SM se realizó a través de la correlación de Spearman mientras que la comparación de grupos acumulados de componentes de SM y cambios hematológicos se realizó con el test de Kruskal-Wallis y posterior análisis pos hoc de Bonferroni. RESULTADOS: Se analizaron los datos de 285 participantes, 31.2% hombres y 68.8% mujeres con una edad media de 46.1 ± 10.5 años. La prevalencia del SM fue de 36.2%, solo las mujeres presentaron cambios en los parámetros hematológicos en presencia de SM. La relación entre los componentes del SM y cambios hematológicos fue fuerte con el aumento del perímetro abdominal y los niveles séricos de triglicéridos; de igual manera, el acúmulo de más de 2 componentes del SM aumenta significativamente los niveles de hemoglobina y hematocrito en mujeres. CONCLUSIONES: En nuestro estudio las mujeres presentaron cambios hematológicos principalmente en la serie roja relacionados al SM y determinados componentes del mismo. Se requieren más estudios poblacionales para corroborar nuestros hallazgos

INTRODUCTION: Metabolic syndrome (MS) is a set of interrelated disorders that produce alterations in various biological systems. OBJECTIVE: This study aimed to evaluate the hematological changes in the presence of metabolic syndrome in health personnel with a balanced diet. MATERIALS AND METHODS: A cross-sectional study was conducted where the database of health personnel who participated in the Plan for the Prevention of Communicable and Non-Communicable Diseases of the Hospital of Huaycan, Peru, was analyzed. The evaluation of the SM was carried out using the criteria of the Latin American Association of Diabetes (ALAD) in the workers who presented a balanced diet according to the questionnaire "FANTASTIC". The relationship between hematological changes and SM components was made through Spearman's correlation while the comparison of accumulated groups of SM components and hematological changes was made with the Kruskal-wallis test andlater Bonferroni's post hoc analysis. RESULTS: Data from 285 participants were analyzed, 31.2% men and 68.8% women with a mean age of 46.1 ± 10.5 years. The prevalence of MS was 36.2%, only women presented changes in hematological parameters in the presence of MS. The relationship between the components of MS and hematological changes was strong with the increase in abdominal circumference and triglycerides; likewise, the accumulation of more than 2 components of MS significantly increases the levels of hemoglobin and hematocrit in women. CONCLUSIONS: In our study the women presented hematological changes mainly in the red series related to MS and certain components of it. Further population-based studies are needed to corroborate our findings

Morbilidad por COVID-19: análisis de los aspectos epidemiológicos, clínicos y diagnósticos / COVID-19 morbidity: analysis of epidemiological, clinical and diagnostic aspects

Introducción: En marzo de 2020 la OMS declaró pandemia a la COVID-19, enfermedad causada por el virus denominado SARS-CoV-2. Cuba, hasta el 9 de junio, reportó 2211 casos y 83 fallecidos; de estos 49 casos eran de Santiago de Cuba, con una letalidad de 6,12. Objetivo: Caracterizar la morbilidad por COVID-19 en Santiago de Cuba según aspectos epidemiológicos, clínicos y de diagnóstico seleccionados. Métodos: Estudio descriptivo transversal con los 49 pacientes confirmados en la provincia. Se efectuó la revisión de base de datos, estadísticas, historias epidemiológicas y clínicas. Se calcularon las tasas de incidencia, media aritmética y mediana, diferencia porcentual de tasas y prueba exacta de Fischer. Se utilizó el software EPIDAT con un nivel de confianza 95 por ciento y significancia ≤ 0,05 para determinar asociación estadística. Resultados: La tasa de incidencia fue 4,7 por 1000 habitantes. Los municipios comprometidos fueron Santiago, Contramaestre y Palma Soriano. El mayor riesgo estuvo en el grupo de los mayores de 60 años, con síntomas frecuentes tos, fiebre y rinitis. El 26,53 por ciento se encontró asintomático. Las principales comorbilidades asociadas fueron hipertensión arterial, trastornos neurológicos y respiratorios. Los procedimientos diagnósticos informaron RT-PCR positiva, LDH elevada, proteína C reactiva, hiperglucemia e infiltrado inflamatorio difuso pulmonar. Existió asociación estadística entre el periodo de evolución, 7 y más días desde el inicio de síntomas al ingreso, y el nivel de gravedad. Conclusiones: El mayor riesgo de enfermar y fallecer se constató en edades más avanzadas de la vida. Los síntomas más frecuentes se comportaron de manera similar a lo descrito en la bibliografía consultada, así como los resultados de laboratorio. La demora en acudir a instituciones de salud y comorbilidades asociadas constituyeron un riesgo, de evolucionar hacia la gravedad y muerte(AU)

Introduction: COVID-19, a disease caused by the virus named SARS-CoV-2, was declared pandemic by the WHO in March 2020. Until 9 June Cuba had reported 2 211 cases and 83 deaths. Forty-nine of these cases were from Santiago de Cuba, for a lethality of 6.12. Objective: Characterize COVID-19 morbidity in Santiago de Cuba based on the analysis of selected epidemiological, clinical and diagnostic aspects. Method: A descriptive cross-sectional study was conducted of the 49 patients confirmed in the province. A review was performed of databases, statistics, and clinical and epidemiological records. Estimation was made of incidence rates, arithmetic mean and median, percentage difference between the rates, and Fischer's exact test. Statistical association was determined with the software EPIDAT, using a confidence level of 95 percent and a significance level of ≤ 0.05. Results: The incidence rate was 4.7 per 1 000 inhabitants. The municipalities involved were Santiago, Contramaestre and Palma Soriano. The greatest risk lay in patients aged over 60 years, among whom coughing, fever and rhinitis were common symptoms. Of the patients studied, 26.53 percent were asymptomatic. The main associated comorbidities were hypertension and neurological and respiratory disorders. The results of the diagnostic procedures applied were positive RT-PCR, high LDH, C-reactive protein, hyperglycemia and diffuse inflammatory pulmonary infiltrate. A statistical association was found between the evolution period, 7 and more days from symptom onset to admission, and the degree of severity. Conclusions: The highest risk of becoming ill and dying was found in the most advanced ages of life. The most common symptoms behaved in a manner similar to the one described in the bibliography consulted, and so did the laboratory results obtained. Delay in reporting to health institutions and associated comorbidities were risks for progression to severity and death(AU)

Pregabalin as a premedication for anxiety in patients undergoing plastic surgery: randomized double-blind, placebo-controlled study.

OBJECTIVE: To evaluate the usefulness of premedication with 75 mg pregabalin orally to reduce the degree of preoperative anxiety in patients scheduled for plastic surgery procedures. METHOD: A controlled randomized double-blind clinical trial that analyzed two groups of patients: 75 mg pregabalin tablet (Pg) against placebo tablet (Pl). Efficacy was assessed using the visual anxiety scale (VAS) with two measurements, the first without medication and the second 70 minutes after the drug was taken. RESULTS: One hundred patients were evaluated, fifty received pregabalin and fifty placebo, baseline VAS score showed an general average of 4.6 ± 1.9 points, significantly higher in the Pg group (Pg 5.2 ± 2.1 points vs 4.1 ± 1.6 points Pl; p = 0.0035). The VAS score after premedication was 3.9 ± 2.1 points, significantly lower in the Pg group (Pg 3.2 ± 1.6 points vs 4.6 ± 2.3 Pl points, p = 0.0006). CONCLUSION: Premedication 75 mg pregabalin orally decreases the degree of preoperative anxiety in adult patients scheduled for plastic surgery procedures.

OBJETIVO: Evaluar la utilidad de la premedicación con 75 mg de pregabalina por vía oral como dosis única para disminuir el grado de ansiedad preoperatoria en pacientes sometidos a cirugía plástica. MÉTODO: Ensayo clínico controlado, prospectivo, aleatorizado, doble ciego, que analizó dos grupos de pacientes: pregabalina tableta de 75 mg (grupo Pg) contra tableta placebo (grupo Pl). La eficacia se evaluó utilizando la escala visual de ansiedad (EVa) con dos mediciones, la primera sin medicación y la segunda 70 minutos después de tomar la cápsula. RESULTADOS: Se evaluaron 100 pacientes: 50 que recibieron pregabalina y 50 placebo. La puntuación basal de la EVa mostró un promedio general de 4.6 ± 1.9 puntos, significativamente mayor en el grupo Pg (5.2 ± 2.1 puntos en Pg vs. 4.1 ± 1.6 puntos en Pl; p = 0.0035). El puntaje en la EVa posterior a la premedicación fue de 3.9 ± 2.1 puntos, significativamente menor en el grupo Pg (3.2 ± 1.6 puntos en Pg vs. 4.6 ± 2.3 puntos en Pl; p = 0.0006). CONCLUSIÓN: La premedicación con 75 mg de pregabalina disminuye el grado de ansiedad preoperatoria en pacientes que serán intervenidos de cirugía plástica.

Astrocyte-mediated switch in spike timing-dependent plasticity during hippocampal development.

Presynaptic spike timing-dependent long-term depression (t-LTD) at hippocampal CA3-CA1 synapses is evident until the 3rd postnatal week in mice, disappearing during the 4th week. At more mature stages, we found that the protocol that induced t-LTD induced t-LTP. We characterized this form of t-LTP and the mechanisms involved in its induction, as well as that driving this switch from t-LTD to t-LTP. We found that this t-LTP is expressed presynaptically at CA3-CA1 synapses, as witnessed by coefficient of variation, number of failures, paired-pulse ratio and miniature responses analysis. Additionally, this form of presynaptic t-LTP does not require NMDARs but the activation of mGluRs and the entry of Ca2+ into the postsynaptic neuron through L-type voltage-dependent Ca2+ channels and the release of Ca2+ from intracellular stores. Nitric oxide is also required as a messenger from the postsynaptic neuron. Crucially, the release of adenosine and glutamate by astrocytes is required for t-LTP induction and for the switch from t-LTD to t-LTP. Thus, we have discovered a developmental switch of synaptic transmission from t-LTD to t-LTP at hippocampal CA3-CA1 synapses in which astrocytes play a central role and revealed a form of presynaptic LTP and the rules for its induction.

Adenosine Receptor-Mediated Developmental Loss of Spike Timing-Dependent Depression in the Hippocampus.

Critical periods of synaptic plasticity facilitate the reordering and refining of neural connections during development, allowing the definitive synaptic circuits responsible for correct adult physiology to be established. Presynaptic spike timing-dependent long-term depression (t-LTD) exists in the hippocampus, which depends on the activation of NMDARs and that probably fulfills a role in synaptic refinement. This t-LTD is present until the third postnatal week in mice, disappearing in the fourth week of postnatal development. We were interested in the mechanisms underlying this maturation related loss of t-LTD and we found that at CA3-CA1 synapses, presynaptic NMDA receptors (pre-NMDARs) are tonically active between P13 and P21, mediating an increase in glutamate release during this critical period of plasticity. Conversely, at the end of this critical period (P22-P30) and coinciding with the loss of t-LTD, these pre-NMDARs are no longer tonically active. Using immunogold electron microscopy, we demonstrated the existence of pre-NMDARs at Schaffer collateral synaptic boutons, where a decrease in the number of pre-NMDARs during development coincides with the loss of both tonic pre-NMDAR activation and t-LTD. Interestingly, this t-LTD can be completely recovered by antagonizing adenosine type 1 receptors (A1R), which also recovers the tonic activation of pre-NMDARs at P22-P30. By contrast, the induction of t-LTD was prevented at P13-P21 by an agonist of A1R, as was tonic pre-NMDAR activation. Furthermore, we found that the adenosine that mediated the loss of t-LTD during the fourth week of development is supplied by astrocytes. These results provide direct evidence for the mechanism that closes the window of plasticity associated with t-LTD, revealing novel events probably involved in synaptic remodeling during development.

Cardiac Biomarker Release after Endurance Exercise in Male and Female Adults and Adolescents.

OBJECTIVES: To compare the responses of high-sensitivity cardiac troponin T (hs-cTnT) and NH2-terminal probrain natriuretic peptide (NT-proBNP) after 60 minutes of swimming in male and female adults and adolescents with different pubertal status. STUDY DESIGN: Adolescent swimmers (25 male and 25 female) and adult swimmers (7 male and 9 female) participated in a 60-minute maximal swimming test with serial assessment of hs-cTnT and NT-proBNP at rest, immediately postexercise, and at 1, 3, 6, 12, and 24 hours postexercise. Adolescents were classified according to pubertal status: Tanner stages 3 (n = 14), 4 (n = 22), and 5 (n = 14). RESULTS: Exercise resulted in an increase in both biomarkers. hs-cTnT responses to exercise were similar in adolescents with different pubertal status and adults, although there was substantial individual variability in peak hs-cTnT, with the upper reference limit exceeding in 62% of the participants. Postexercise kinetics for hs-cTnT were largely consistent across all groups with a return to near baseline levels 24 hours postexercise. The male participants showed higher values of hs-cTnT at baseline and postexercise. All groups had similar NT-proBNP responses to acute exercise and recovery. One swimmer exceeded the upper reference limit for NT-proBNP. CONCLUSIONS: An exercise-associated increase in hs-cTnT and NT-proBNP occurred in response to a 60-minute maximal swimming test that was independent of pubertal status/adolescent vs adults. The present data also suggests that baseline and postexercise hs-cTnT values are higher in male compared with female, with no sex differences in NT-proBNP values.

Localización infrecuente del quiste hidatídico suprarrenal primario / Uncommon location of the primary adrenal hydatid cyst

El quiste hidatídico suprarrenal primario es una patología muy infrecuente por su localización y se encuentra en este órgano en menos del 0,5 por ciento de los casos, incluso en países con presencia endémica del Echinococcus. La mayoría de los quistes hidatídicos suprarrenales son asintomáticos, siendo el diagnóstico un hallazgo incidental. Las pruebas serológicas para el diagnóstico pueden ser negativas en muchos casos y el tratamiento es en su mayoría quirúrgico, con múltiples vías de abordaje. Es una patología poco común; el diagnóstico, manejo, tratamiento y vías de abordaje no se encuentran aún muy establecidos. Con este artículo tratamos de realizar un acercamiento más certero en cuanto a estos aspectos(AU)

The primary adrenal hydatid cyst is a very rare disease for its location and it is found in less than 0.5 percent of the cases, even in countries with endemic presence of Echinococcus. Most adrenal hydatid cysts are asymptomatic, and the diagnosis is an incidental finding, the serological tests for the diagnosis are negative in many cases and the treatment is mostly surgical, with multiple surgical approaches. It is a rare pathology whose diagnosis, management, treatment and surgical approaches are not yet well established. This article was intended to address these aspects in a more accurate way(AU)

Blackwater fever like in murine malaria.

Blackwater fever (BWF) is the term used to designate the occurrence of hemoglobin pigments in the urine of patients infected with malaria parasites. BWF is more often associated with Plasmodium falciparum infection in man. The pathogenesis of BWF has not been explained satisfactorily. In the present study, the clinical and pathological observations made upon CD1 mice infected with Plasmodium yoelii yoelii lethal strain with clinical signs of hemoglobinuria and acute renal failure were evaluated. From the 40 P. yoelii yoelii-infected mice, 14 presented hemoglobinuria. In the observations, it was emphasized that hemoglobinuria occurred in the animals 1-2 days before they die. At 6 days post-infection, infected hemoglobinuric mice (HM) exhibited clinical signs such as dark red urine, apnea, and evident oliguria and hematuria; urine microscopical examination showed very few red blood cells. The entire non hemoglobinuric infected mice had a high parasitemia preceding the time of death, while the HM parasitemia was just detectable. In HM, marked hepatosplenomegaly, anemia, and renal and hepatic dysfunction were observed with the blood chemistry analysis at 6 days post-infection. Severe renal lesions were demonstrated in histopathological and scanning electron microscopy samples. Occlusion and necrosis of convoluted tubules were the main lesions found. The conditions required for the experimental production of hemoglobinuria in CD1 mouse infected by P. yoelii yoelii is still unknown. The clinical picture of a BWF, like in our rodents, was produced exclusively by the interaction between the parasite and its host. Results showed that hemoglobinuria in CD1 mice infected with P. yoelii yoelii and BWF in man infected with P. falciparum are similar in their pathogenesis.

Validity of the Wingate anaerobic test for the evaluation of elite runners.

This study aimed to determine performance differences, based on the Wingate anaerobic test (WAnT), between homogeneous groups of elite male and female runners competing at distances ranging from 100 m to the marathon. We also attempted to establish a link between running ability and performance as measured by the WAnT. In total, 116 world-class runners (86 men and 30 woman) volunteered to participate in our study. Subjects were tested for peak power (PP, 5-second output) and mean power (MP, 30-second output) using WAnT procedures. Runners were classified into groups according to their best performances times. For male runners, PP and MP outputs decreased with increasing distance (p < 0.001). This trend was also true for female runners (p < 0.005). However, for both sexes, there were no significant differences in the PP values among 100-, 400-, and 800-m runners, and there were also no differences in the MP values for subjects that ran distances of 100 m compared with the values for subjects that ran distances of 400 and 800 m. In addition, no significant differences were observed in the PP and MP values between subjects that ran distances of 800, 1,500, and 3,000 m. Performance in the WAnT was not significantly associated with running performance in any distance event. The results of this study indicate that the WAnT is not a useful tool for the evaluation of elite runners.

[Update on and evaluation of an IgG ELISA technique for the diagnosis of human hydatidosis]. / Puesta a punto y valoración de una técnica ELISA IgG para el diagnóstico de hidatidosis humanas.

The methodology to carry out a diagnostic test for hydatid disease is reported. Full hydatid fluid was used as antigen and specific IgG was detected. 61 sera from patients in whom hydatid disease was subsequently confirmed at surgery, 28 sera of patients with other diseases and 16 sera from blood donors were evaluated. The sensitivity and specificity were established on the basis of statistical criteria. In the group of patients with hydatid disease, sensitivity was 98.4%, with only one nonreactive serum. Specificity was 60.6% and was higher with increasing age of the patients or depending on the cyst localization (it was higher in hepatic than in pulmonary cysts).

The prevalence of Cryptosporidium species in children in day care centres and primary schools in Salamanca (Spain): an epidemiological study.

Cryptosporidium species was found in 1.8% (2/113 children in the first sampling) and 1.9% (2/107 children in the second sampling) of the children studied in 11 day care centres. All cases were observed in children younger than 3 years of age, who were immunocompetent and asymptomatic. No cases of parasitization by Cryptosporidium species was detected in 67 children aged 5-14 years attending 7 primary schools.

[Incidence of Cryptosporidium sp in patients treated in a general hospital. Technics for the identification of oocysts in feces]. / Incidencia de Cryptosporidium sp en pacientes asistidos en un hospital general. Técnicas para la identificación de ooquistes en heces.

In feces referred for parasite investigation from 1973 patients of the Hospital Clinico Universitario in Salamanca, 27 instances of infestation by Cryptosporidium sp (1.5% of all investigated patients) were detected in 19 children (1.4%) and 8 adults (2.2%). The incidence in patients with antibodies against the human immunodeficiency virus (HIV) was 12.5%, in contrast with 1.25% in patients without anti-HIV antibodies. 55.5% of the instances of Cryptosporidium sp infestation were found in children less than 4 years old. The higher incidence was in winter and spring. The association with other enteropathogens was found in 14.8%. Diarrhea and abdominal pain were the most common clinical features of cryptosporidial disease. Chronic diarrhea was found in two adult patients with acquired immunodeficiency syndrome. In immunocompromised children and adults asymptomatic carriers were found. The sensitivity and specificity of immunofluorescence testing with monoclonal antibodies as compared with Ziehl-Neelsen stain for the detection of Cryptosporidium sp oocysts were 100%.