3-Acetylpyridine-induced ataxic-like motor impairments are associated with plastic changes in the Purkinje cells of the rat cerebellum.

Ataxias are characterized by aberrant movement patterns closely related to cerebellar dysfunction. Purkinje cell axons are the sole outputs from the cerebellar cortex, and dysfunctional activity of Purkinje cells has been associated with ataxic movements. However, the synaptic characteristics of Purkinje cells in cases of ataxia are not yet well understood. The nicotinamide antagonist 3-acethylpyridine (3-AP) selectively destroys inferior olivary nucleus neurons so it is widely used to induce cerebellar ataxia. Five days after 3-AP treatment (65mg/kg) in adult male Sprague-Dawley rats, motor incoordination was revealed through BBB and Rotarod testing. In addition, in Purkinje cells from lobules V-VII of the cerebellar vermis studied by the Golgi method, the density of dendritic spines decreased, especially the thin and mushroom types. Western blot analysis showed a decrease in AMPA and PSD-95 content with an increase of the α-catenin protein, while GAD-67 and synaptophysin were unchanged. Findings suggest a limited capacity of Purkinje cells to acquire and consolidate afferent excitatory inputs and an aberrant, rigid profile in the movement-related output patterns of Purkinje neurons that likely contributes to the motor-related impairments characteristic of cerebellar ataxias.

Prenatal predictors of motor function in children with open spina bifida: a retrospective cohort study.

OBJECTIVE: To identify predictors for intact motor function (MF) at birth and at 12 months of life in babies with prenatally versus postnatally repaired open spina bifida (OSB). DESIGN: Retrospective cohort study. SETTING: Texas Children's Hospital, 2011-2018. POPULATION: Patients who underwent either prenatal or postnatal OSB repair. METHODS: Prenatal MF of the lower extremities was evaluated by ultrasound following a metameric distribution at the time of diagnosis (US1), 6 weeks postoperatively (or 6 weeks after initial evaluation in postnatally repaired cases) (US2) and at the last ultrasound before delivery (US3). At birth and at 12 months, MF was assessed clinically. Intact MF (S1) was defined as the observation of plantar flexion of the ankle. Results from logistic regression analysis are expressed as odds ratios (95% confidence intervals, P values). RESULTS: A total of 127 patients were included: 93 with prenatal repair (51 fetoscopic; 42 open hysterotomy repair) and 34 with postnatal repair. In the prenatal repair group, predictors for intact MF at birth and at 12 months included: absence of clubfeet (OR 11.3, 95% CI 3.2-39.1, P < 0.01; OR 10.8 95% CI 2.4-47.6, P < 0.01); intact MF at US1 (OR 19.7, 95% CI 5.0-76.9, P < 0.01; OR 8.7, 95% CI 2.0-38.7, P < 0.01); intact MF at US2 (OR 22, 95% CI 6.5-74.2, P < 0.01; OR 13.5, 95% 3.0-61.4, P < 0.01); intact MF at US3 (OR 13.7, 95% CI 3.4-55.9, P < 0.01; OR 12.6, 95% CI 2.5-64.3, P < 0.01); and having a flat lesion (OR 11.2, 95% CI 2.4-51.1, P < 0.01; OR 4.1, 95% CI 1.1-16.5, P = 0.04). In the postnatal repair group, the only predictor of intact MF at 12 months was having intact MF at birth (OR 15.2, 95% CI 2.0-113.3, P = 0.03). CONCLUSIONS: The detection of intact MF in utero from mid-gestation to delivery predicts intact MF at birth and at 12 months in babies who undergo prenatal OSB repair. TWEETABLE ABSTRACT: Detection of intact motor function in utero predicts intact motor function at birth and at 1 year in fetuses who undergo prenatal OSB repair.

Longitudinal evaluation of motor function in patients who underwent prenatal or postnatal neural tube defect repair.

OBJECTIVE: To compare the evolution of motor function from mid-gestation to 12 months of age between prenatally and postnatally repaired cases of open neural tube defect (ONTD). METHODS: This was a retrospective cohort study of all fetuses that underwent prenatal (fetoscopic or open hysterotomy) or postnatal ONTD repair at a single institution between November 2011 and December 2018. The anatomical level of the lesion was defined as the upper bony spinal defect at initial magnetic resonance imaging assessment. Prenatal motor function of the lower extremities was evaluated by ultrasound according to the metameric level of the neurological lesion, based on the methodology of Carreras et al. Fetal motor function was assessed at referral, at 6 weeks after surgery in prenatally repaired cases or 6 weeks after referral in postnatally repaired cases (6-week follow-up) and at the last scan before delivery. In addition, motor function was assessed by a detailed neurological examination at birth and 12 months of age. First sacral (S1) neurological level of the lesion was considered as intact motor function. For statistical comparisons, we attributed numerical scores to each neurological level and motor function was expressed as median (range) neurological level. Motor function (as numerical score) and the proportion of cases with intact motor function and with motor function two or more levels better than expected based on the anatomical level of the lesion were compared between the prenatal- and postnatal-repair groups. Fetal motor function was compared to the anatomical level of the lesion at referral and a better motor function was defined when it was two or more levels better than the anatomical level of the lesion. To assess the evolution of motor function, we compared motor function at referral with that at each follow-up assessment using paired t-tests. RESULTS: We included 127 patients with ONTD, of whom 93 underwent prenatal (51 fetoscopic and 42 open hysterotomy) and 34 postnatal repair. At the time of referral, cases in the prenatal- and postnatal-repair groups presented with a similar anatomical level of lesion (L3 (T9-S1) vs L3 (T7-S1); P = 0.52), similar motor function (S1 (L1-S1) vs S1 (L1-S1); P = 0.52) and a similar proportion of cases with intact motor function (81% vs 79%; P = 0.88) and with motor function two or more levels better than expected based on the anatomical level of the lesion (62% vs 74%; P = 0.24). When compared with prenatally repaired cases, postnatally repaired cases showed worse motor function at birth (S1 (L1-S1) vs L4 (L1-S1); P < 0.01) and at 12 months of age (S1 (L1-S1) vs L4 (L1-S1); P < 0.01). In the prenatal-repair group, motor function remained stable from the time of referral to 12 months of age (P = 0.26). Furthermore, the proportion of patients with intact motor function at referral (81% (75/93)) was similar to that at the 6-week follow-up (74% (64/87)), at the last scan before birth (74% (42/57)), at birth (68% (63/93)) and at 12 months of age (67% (39/58)) in the prenatal-repair group. In the postnatal-repair group, worse motor function, starting from the third trimester to 12 months of age, was observed. The proportion of patients with intact motor function at referral (79% (27/34)) was similar to that at 6-week follow-up (80% (12/15); P = 0.92), but was lower at the last assessment before birth (25% (2/8); P < 0.01), at birth (24% (8/34); P < 0.01) and at 12 months of age (28% (7/25); P < 0.01). Similar findings were noted when assessing the evolution of the proportion of cases with motor function two or more levels better than expected based on the anatomical level of the lesion in each group. CONCLUSIONS: Infants with ONTD that underwent postnatal repair had worse motor function at birth and at 12 months of age than at mid-gestation and when compared with infants that underwent prenatal ONTD repair. Prenatal motor function assessment by ultrasound is an adequate tool to identify those infants who should have a good clinical motor function after delivery. Information obtained by fetal motor function assessment can have an important role for patient counseling and case selection for surgery. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.

Outcomes of cholera and measles outbreak alerts in the Democratic Republic of Congo.

SETTING: In 1995, a rapid response project for humanitarian and medical emergencies, including outbreak responses, named 'Pool d'Urgence Congo' (PUC), was implemented in the Democratic Republic of Congo by Médecins Sans Frontières. OBJECTIVE: To assess the outcomes of cholera and measles outbreak alerts that were received in the PUC surveillance system between 2016 and 2018. DESIGN: This was a retrospective cross-sectional study. RESULTS: Overall, 459 outbreak alerts were detected, respectively 69% and 31% for cholera and measles. Of these, 32% were actively detected and 68% passively detected. Most alerts (90%) required no intervention and 10% of alerts had an intervention. There were 25% investigations that were not carried out despite thresholds being met; 17% interventions were not performed, the main reported reason being PUC operational capacity was exceeded. Confirmed cholera and measles outbreaks that met an investigation threshold comprised respectively 90% and 76% of alerts; 59% of measles investigations were followed by a delayed outbreak response of ⩾14 days (n = 10 outbreaks). CONCLUSION: Some alerts for cholera and measles outbreaks that were detected in the PUC system did not lead to a response even when required; the main reported reason was limited operational capacity to respond to all of them.

Comparison of brain microstructure after prenatal spina bifida repair by either laparotomy-assisted fetoscopic or open approach.

OBJECTIVE: To compare prenatal and postnatal brain microstructure between infants that underwent fetoscopic myelomeningocele (MMC) repair and those that had open-hysterotomy repair. METHODS: This was a longitudinal retrospective cohort study of 57 fetuses that met the Management of Myelomeningocele Study (MOMS) trial criteria and underwent prenatal MMC repair, by a fetoscopic (n = 27) or open-hysterotomy (n = 30) approach, at 21.4-25.9 weeks' gestation. Fetoscopic repair was performed under CO2 insufflation, according to our protocol. Diffusion-weighted magnetic resonance imaging (MRI) was performed before surgery in 30 cases (14 fetoscopic and 16 open), at 6 weeks postsurgery in 48 cases (24 fetoscopic and 24 open) and within the first year after birth in 23 infants (five fetoscopic and 18 open). Apparent diffusion coefficient (ADC) values from the basal ganglia, frontal, occipital and parietal lobes, mesencephalon and genu as well as splenium of the corpus callosum were calculated. ADC values at each of the three timepoints (presurgery, 6 weeks postsurgery and postnatally) and the percentage change in the ADC values between the timepoints were compared between the fetoscopic-repair and open-repair groups. ADC values at 6 weeks after surgery in the two prenatally repaired groups were compared with those in a control group of eight healthy fetuses that underwent MRI at a similar gestational age (GA). Comparison of ADC values was performed using the Student's t-test for independent samples (or Mann-Whitney U-test if non-normally distributed) and multivariate general linear model analysis, adjusting for GA or age at MRI and mean ventricular width. RESULTS: There were no differences in GA at surgery or GA/postnatal age at MRI between the groups. No significant differences were observed in ADC values in any of the brain areas assessed between the open-repair and fetoscopic-repair groups at 6 weeks after surgery and in the first year after birth. No differences were detected in the ADC values of the studied areas between the control and prenatally repaired groups, except for significantly increased ADC values in the genu of the corpus callosum in the open-hysterotomy and fetoscopic-repair groups. Additionally, there were no differences between the two prenatally repaired groups in the percentage change in ADC values at any of the time intervals analyzed. CONCLUSIONS: Fetoscopic MMC repair has no detectable effect on brain microstructure when compared to babies repaired using an open-hysterotomy technique. CO2 insufflation of the uterine cavity during fetoscopy does not seem to have any isolated deleterious effects on fetal brain microstructure. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Chorioamniotic membrane separation following fetal myelomeningocele repair: incidence, risk factors and impact on perinatal outcome.

OBJECTIVES: Prenatal myelomeningocele (MMC) repair has been shown to provide significant benefits to the infant, decreasing the postnatal need for ventriculoperitoneal shunt and improving motor outcome. Chorioamniotic membrane separation (CAS) is a potential complication following prenatal MMC repair and may increase the risk of preterm prelabor rupture of membranes (PPROM) and preterm birth. The objectives of this study were: (1) to evaluate the incidence of CAS after prenatal MMC repair; (2) to determine risk factors associated with its occurrence; and (3) to assess its association with adverse perinatal outcomes. METHODS: This was a retrospective cohort study of patients who underwent fetal MMC repair between November 2011 and December 2018. Surgery was performed using either a fetoscopic (laparotomy or exteriorized uterus) approach or an open-hysterotomy approach. Eligibility criteria were those reported in the Management of Myelomeningocele Study. If CAS was detected on ultrasound (US), its severity was graded as 'mild' if amnion detachment involved < 25% of the uterine cavity, 'moderate' if it involved 25-50% and 'severe' if it involved > 50%. Evolution of CAS was classified as stable, increasing or decreasing based on the difference in severity grading between the time at first diagnosis and the last US scan before delivery. Logistic regression analysis was performed to identify pre- or perisurgical factors associated with the development of CAS and to determine the risk of adverse perinatal outcome associated with CAS. RESULTS: In total, 91 cases were included. Fetoscopic or open-hysterotomy repair of MMC was performed in 52/91 (57.1%) and 39/91 (42.9%) cases, at a median gestational age (GA) of 25.0 weeks (range, 22.9-26.0 weeks) and 25.0 weeks (range, 21.3-25.9 weeks), respectively. CAS was diagnosed in 31/91 (34.1%) patients, at a median GA of 28.1 weeks (range, 24.4-37.6 weeks). Anterior placenta was identified as a risk factor for the postoperative development of CAS (odds ratio (OR), 3.72 (95% CI, 1.46-9.5); P < 0.01). This risk was dependent on the repair technique. An anterior placenta significantly increased the risk of CAS after fetoscopic repair (OR, 3.94 (95% CI, 1.14-13.6); P = 0.03) but not after open repair (OR, 2.8 (95% CI, 0.6-12.5); P = 0.16). There was no significant difference in the rate of CAS after fetoscopic repair (21/52 (40.4%)) vs open-hysterotomy repair (10/39 (25.6%)) (P = 0.14), nor were there any differences in GA at diagnosis of CAS, interval between surgery and diagnosis, distribution of CAS severity or progression of CAS between the two groups. CAS increased the risk of PPROM (50% in those with vs 12% in those without CAS) (OR, 7.6 (95% CI, 2.5-21.9); P < 0.01) and preterm delivery (70% vs 38%) (OR, 3.2 (95% CI, 1.3-8.1); P < 0.01). Fetoscopically repaired cases with CAS had a higher rate of PPROM (12/20 (60.0%) vs 2/31 (6.5%); P < 0.01) and preterm delivery (13/20 (65.0%) vs 5/31 (16.1%); P < 0.01) than those that did not develop CAS, while the differences were not significant in cases with open-hysterotomy repair. Early detection of CAS (before 30 weeks' gestation) was a risk factor for preterm delivery (90% before 30 weeks vs 36% at or after 30 weeks) (OR, 15.7 (95% CI, 2.3-106.3); P < 0.01). There was no association between PPROM or preterm delivery and the severity or progression of CAS. CONCLUSIONS: The presence of an anterior placenta was the only factor that increased the risk for CAS after fetoscopic MMC repair. Detection of CAS after fetoscopic MMC repair significantly increases the risk for PPROM and preterm delivery. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Prenatal brain imaging for predicting need for postnatal hydrocephalus treatment in fetuses that had neural tube defect repair in utero.

OBJECTIVE: To determine if brain imaging in fetuses that underwent prenatal repair of neural tube defect (NTD) can predict the need for postnatal hydrocephalus treatment (HT) in the first year postpartum. METHODS: This was a retrospective study of fetuses diagnosed with open NTD that had in-utero myelomeningocele repair between April 2014 and April 2016. Independent variables were collected from four chronological sets of fetal images: presurgery ultrasound, presurgery magnetic resonance imaging (MRI), 6-week postsurgery MRI and predelivery ultrasound. The following independent variables were collected from all image sets unless otherwise noted: gestational age, head circumference, mean ventricular width, ventricular volume (MRI only), hindbrain herniation (HBH) score (MRI only), and level of lesion (LOL), defined as the upper bony spinal defect (presurgery ultrasound only). Based on these measurements, additional variables were defined and calculated including change in degree of HBH, ventricular width growth (mm/week) and ventricular volume growth (mL/week). The need for HT (by either ventriculoperitoneal shunt or endoscopic third ventriculostomy with choroid plexus cauterization) was determined by a pediatric neurosurgeon using clinical and radiographic criteria; a secondary analysis was performed using the MOMS trial criteria for hydrocephalus. The predictive value of each parameter was assessed by receiver-operating characteristics curve and logistic regression analyses. RESULTS: Fifty affected fetuses were included in the study, of which 32 underwent open hysterotomy and 18 fetoscopic repair. Two neonates from the open hysterotomy group died and were excluded from the analysis. The mean gestational ages for the presurgery ultrasound, presurgery MRI, postsurgery MRI and predelivery ultrasound were 21.8 ± 2.1, 22.0 ± 1.8, 30.4 ± 1.6 and 31.0 ± 4.9 weeks, respectively. A total of 16 subjects required HT. The area under the curve (AUC) of predictive accuracy for HT showed that HBH grading on postsurgery MRI had the strongest predictive value (0.86; P < 0.01), outperforming other predictors such as postsurgery MRI ventricular volume (0.73; P = 0.03), MRI ventricular volume growth (0.79; P = 0.01), change in HBH (0.82; P = 0.01), and mean ventricular width on predelivery ultrasound (0.73; P = 0.01). Other variables, such as LOL, mean ventricular width on presurgery ultrasound, mean ventricular width on presurgery and postsurgery MRI, and ventricular growth assessment by MRI or ultrasound, had AUCs < 0.7. Optimal cut-offs of the variables with the highest AUC were evaluated to improve prediction. A combination of ventricular volume growth ≥ 2.02 mL/week and/or HBH of 3 on postsurgery MRI were the optimal cut-offs for the best prediction (odds ratio (OR), 42 (95% CI, 4-431); accuracy, 84%). Logistic regression analyses showed that persistence of severe HBH 6 weeks after surgery by MRI is one of the best predictors for HT (OR, 39 (95% CI, 4-369); accuracy, 84%). There was no significant change in the results when the MOMS trial criteria for hydrocephalus were used as the dependent variable. CONCLUSIONS: Persistence of HBH on MRI 6 weeks after prenatal NTD repair independently predicted the need for postnatal HT better than any ultrasound- or other MRI-derived measurements of ventricular characteristics. These results should aid in prenatal counseling and add support to the hypothesis that HBH is a significant driver of hydrocephalus in myelomeningocele patients. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Imágenes cerebrales prenatales para predecir el tratamiento postnatal de la hidrocefalia en fetos con reparación de defectos del tubo neural OBJETIVOS: Determinar si las imágenes cerebrales en fetos que se sometieron a reparación prenatal de defectos del tubo neural (DTN) pueden predecir la necesidad de tratamiento postnatal de la hidrocefalia (TH) en el primer año después del parto. MÉTODOS: Este fue un estudio retrospectivo de fetos diagnosticados con DTN aun abierto cuyo mielomeningocele fue reparado en el útero, entre abril de 2014 y abril de 2016. Se recolectaron variables independientes de cuatro conjuntos cronológicos de imágenes fetales: ecografía prequirúrgica, imágenes por resonancia magnética (IRM) prequirúrgica, imágenes por resonancia magnética (IRM) posquirúrgica a las seis semanas y ecografía previa al parto. Las siguientes variables independientes se recolectaron de todos los conjuntos de imágenes, a menos que se indique lo contrario: edad gestacional, perímetro cefálico, ancho ventricular medio, volumen ventricular (IRM solamente), puntaje de hernia del rombencéfalo (HR) (IRM solamente) y nivel de lesión (NDL), definido como el defecto espinal óseo superior (ecografía prequirúrgica solamente). A partir de estas mediciones se definieron y calcularon variables adicionales, como el cambio en el grado de HR, el aumento del ancho ventricular (mm/semana) y el aumento del volumen ventricular (mL/semana). La necesidad de TH (ya sea por derivación ventriculoperitoneal o por ventriculostomía endoscópica del tercer ventrículo y cauterización del plexo coroideo) fue determinada por un neurocirujano pediátrico utilizando criterios clínicos y radiográficos; se realizó un análisis secundario utilizando los criterios del estudio MOMS para la hidrocefalia. El valor predictivo de cada parámetro se evaluó mediante un análisis de la curva de la característica operativa del receptor y de la regresión logística. RESULTADOS: Se incluyeron en el estudio 50 fetos afectados, de los cuales 32 se sometieron a histerotomía abierta y 18 a reparación fetoscópica. Dos de los recién nacidos del grupo de histerotomía abierta murieron y fueron excluidos del análisis. Las edades gestacionales medias para la ecografía prequirúrgica, la IRM prequirúrgica, la IRM postoperatoria y la ecografía previa al parto fueron 21,8 ±2,1; 22,0 ±1,8; 30,4 ±1,6 y 31,0 ±4,9 semanas, respectivamente. Un total de 16 sujetos requirieron TH. El área bajo la curva (ABC) de precisión predictiva para la TH mostró que la clasificación de la HR en la IRM postoperatoria tuvo el valor predictivo más fuerte (0,86; P<0.01), por encima de otros valores predictivos como el volumen ventricular en la IRM posquirúrgica (0,73; P=0,03), el crecimiento del volumen ventricular en la IRM (0,79; P=0,01), cambios en la HR (0,82; P=0,01), y el ancho ventricular medio en la ecografía previa al parto (0,73; P=0,01). Otras variables, como el NDL, la anchura ventricular media en la ecografía prequirúrgica, la anchura ventricular media en la IRM prequirúrgica y posquirúrgica, y la evaluación del crecimiento ventricular mediante ecografía o IRM, tuvieron AUC <0,7. Para mejorar la predicción se evaluaron los límites óptimos de las variables con las AUC más altas. Los límites óptimos para la mejor predicción (razones de momios [RM], 42 [IC 95%: 4-431]; precisión, 84%) fueron una combinación de crecimiento del volumen ventricular ≥2,02 mL/semana y/o HR de 3 en la IRM postoperatoria. Los análisis de regresión logística mostraron que la persistencia de la HR grave a las 6 semanas después de la cirugía en IRM es uno de los mejores predictores de la TH (RM, 39 (IC 95%: 4-369); precisión, 84%). Los resultados no cambiaron de forma significativa cuando se utilizaron los criterios del estudio MOMS para la hidrocefalia como variable dependiente. CONCLUSIONES: La persistencia de la HR en la IRM 6 semanas después de la reparación prenatal de DTN predijo independientemente la necesidad de la TH postnatal mejor que cualquier ecografía o que otras mediciones de las características ventriculares a partir de IRM. Estos resultados deberían ayudar en el asesoramiento previo al parto y a apoyar la hipótesis de que la HR es un impulsor significativo de la hidrocefalia en pacientes con mielomeningocele.

Does fetoscopic or open repair for spina bifida affect fetal and postnatal growth?

OBJECTIVE: The effect of fetoscopic myelomeningocele (MMC) repair on fetal growth is unknown. Fetal surgery itself and/or exposure to a carbon dioxide (CO2 ) environment during spina bifida repair may affect placental function and impair fetal growth. Our aim was to assess and compare growth in fetuses, neonates and infants who underwent prenatal fetoscopic or open MMC repair. METHODS: Fetal biometrics were obtained serially using ultrasound after fetoscopic (n = 32) or open hysterotomy (n = 34) MMC repair in utero at a single institution between November 2011 and July 2017. Measurements obtained during growth scans on initial evaluation prior to surgery, and those taken at 6 weeks post-surgery, were transformed into percentiles and compared between groups. Additional neonatal and infant anthropometric measurements, including weight, length/height and head circumference, were also transformed into percentiles and compared between the groups. The proportions of cases in each group with estimated fetal weight (EFW) or postnatal weight < 10th and < 3rd percentiles were calculated and compared. A linear mixed model was used to analyze the serial fetal growth measurements of each parameter, and random intercepts and slopes were used to compare study variables between the study groups. The duration of surgery (skin-to-skin time at fetoscopic and open MMC repair) and duration of CO2 exposure (fetoscopic repair) were evaluated for any effect on the fetal, neonatal or infant biometric percentiles. RESULTS: Fetuses which underwent fetoscopic repair had a larger abdominal circumference percentile at referral (57 ± 21 vs 46 ± 23; P = 0.04). There were no other differences between the two groups in fetal biometric percentiles at the time of referral, 6 weeks post-surgery or at birth. There were no differences between groups in EFW percentile or in proportions of cases with birth weight < 10th and < 3rd percentiles. Linear mixed-model analysis did not show any significant differences in any fetal growth parameter between the groups over time. There were no significant correlations between duration of surgery or duration of CO2 exposure and any of the biometric percentiles evaluated. Postnatal growth showed no significant differences between the groups in weight, height or head circumference percentiles, at 6-18, 18-30 or > 30 months of age. CONCLUSIONS: Babies exposed to fetoscopic or open MMC repair in-utero did not show significant differences in fetal or postnatal growth parameters. These results support the safety of the use of CO2 gas for fetoscopic surgery. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Naegleria fowleri immunization modifies lymphocytes and APC of nasal mucosa.

We investigated whether intranasal immunization with amoebic lysates plus cholera toxin modified the populations of T and B lymphocytes, macrophages and dendritic cells by flow cytometry from nose-associated lymphoid tissue (NALT), cervical lymph nodes (CN), nasal passages (NP) and spleen (SP). In all immunized groups, the percentage of CD4 was higher than CD8 cells. CD45 was increased in B cells from mice immunized. We observed IgA antibody-forming cell (IgA-AFC) response, mainly in NALT and NP. Macrophages from NP and CN expressed the highest levels of CD80 and CD86 in N. fowleri lysates with either CT or CT alone immunized mice, whereas dendritic cells expressed high levels of CD80 and CD86 in all compartment from immunized mice. These were lower than those expressed by macrophages. Only in SP from CT-immunized mice, these costimulatory molecules were increased. These results suggest that N. fowleri and CT antigens are taking by APCs, and therefore, protective immunity depends on interactions between APCs and T cells from NP and CN. Consequently, CD4 cells stimulate the differentiation from B lymphocytes to AFC IgA-positive; antibody that we previously found interacting with trophozoites in the nasal lumen avoiding the N. fowleri attachment to nasal epithelium.

Neutrophils extracellular traps damage Naegleria fowleri trophozoites opsonized with human IgG.

Naegleria fowleri infects humans through the nasal mucosa causing a disease in the central nervous system known as primary amoebic meningoencephalitis (PAM). Polymorphonuclear cells (PMNs) play a critical role in the early phase of N. fowleri infection. Recently, a new biological defence mechanism called neutrophil extracellular traps (NETs) has been attracting attention. NETs are composed of nuclear DNA combined with histones and antibacterial proteins, and these structures are released from the cell to direct its antimicrobial attack. In this work, we evaluate the capacity of N. fowleri to induce the liberation of NETs by human PMN cells. Neutrophils were cocultured with unopsonized or IgG-opsonized N. fowleri trophozoites. DNA, histone, myeloperoxidase (MPO) and neutrophil elastase (NE) were stained, and the formation of NETs was evaluated by confocal microscopy and by quantifying the levels of extracellular DNA. Our results showed N. fowleri induce the liberation of NETs including release of MPO and NE by human PMN cells as exposure interaction time is increased, but N. fowleri trophozoites evaded killing. However, when trophozoites were opsonized, they were susceptible to the neutrophils activity. Therefore, our study suggests that antibody-mediated PMNs activation through NET formation may be crucial for antimicrobial responses against N. fowleri.

Latin American Study of Nutrition and Health (ELANS): rationale and study design.

BACKGROUND: Obesity is growing at an alarming rate in Latin America. Lifestyle behaviours such as physical activity and dietary intake have been largely associated with obesity in many countries; however studies that combine nutrition and physical activity assessment in representative samples of Latin American countries are lacking. The aim of this study is to present the design rationale of the Latin American Study of Nutrition and Health/Estudio Latinoamericano de Nutrición y Salud (ELANS) with a particular focus on its quality control procedures and recruitment processes. METHODS/DESIGN: The ELANS is a multicenter cross-sectional nutrition and health surveillance study of a nationally representative sample of urban populations from eight Latin American countries (Argentina, Brazil, Chile, Colombia, Costa Rica, Ecuador, Perú and Venezuela). A standard study protocol was designed to evaluate the nutritional intakes, physical activity levels, and anthropometric measurements of 9000 enrolled participants. The study was based on a complex, multistage sample design and the sample was stratified by gender, age (15 to 65 years old) and socioeconomic level. A small-scale pilot study was performed in each country to test the procedures and tools. DISCUSSION: This study will provide valuable information and a unique dataset regarding Latin America that will enable cross-country comparisons of nutritional statuses that focus on energy and macro- and micronutrient intakes, food patterns, and energy expenditure. TRIAL REGISTRATION: Clinical Trials NCT02226627.

Protection against Naegleria fowleri infection in mice immunized with Cry1Ac plus amoebic lysates is dependent on the STAT6 Th2 response.

We previously reported that intranasal administration of Cry1Ac protoxin alone or in combination with amoebic lysates increases protection against Naegleria fowleri meningoencephalitis in mice. Those results suggested that both antibody responses and innate immune mechanisms may be participating in the protective effects observed. The present study was aimed to investigate whether the STAT6-induced Th2 immune response is essential for the resistance to N. fowleri infection, conferred by immunization with amoebic lysates plus Cry1Ac. STAT6-deficient (STAT6-/-) and wild-type (STAT6+/+) BALB/c mice were immunized by the intranasal route with a combination of N. fowleri lysates plus Cry1Ac, and subsequently challenged with lethal doses of N. fowleri trophozoites. STAT6+/+ mice displayed 100% protection, while no protection was observed in STAT6-/- mice. Significantly higher titres of Th2-associated IgG1 as well as interleukin-4 (IL-4) were found in STAT6+/+ mice, whereas in STAT6-/- mice significantly more IL-12 and IFN-gamma as well as significantly higher titres of Th1-associated IgG2a were detected. Thus, whereas protected STAT6+/+-immunized mice elicited a Th-2 type inclined immune response that produced predominantly humoral immunity, unprotected STAT6-/- mice exhibited a polarized Th1 type cellular response. These findings suggest that the STAT6-signalling pathway is critical for defence against N. fowleri infection.

Statistical scattering of waves in disordered waveguides: From microscopic potentials to limiting macroscopic statistics.

We study the statistical properties of wave scattering in a disordered waveguide. The statistical properties of a "building block" of length deltaL are derived from a potential model and used to find the evolution with length of the expectation value of physical quantities. In the potential model the scattering units consist of thin potential slices, idealized as delta slices, perpendicular to the longitudinal direction of the waveguide; the variation of the potential in the transverse direction may be arbitrary. The sets of parameters defining a given slice are taken to be statistically independent from those of any other slice and identically distributed. In the dense-weak-scattering limit, in which the potential slices are very weak and their linear density is very large, so that the resulting mean free paths are fixed, the corresponding statistical properties of the full waveguide depend only on the mean free paths and on no other property of the slice distribution. The universality that arises demonstrates the existence of a generalized central-limit theorem. Our final result is a diffusion equation in the space of transfer matrices of our system, which describes the evolution with the length L of the disordered waveguide of the transport properties of interest. In contrast to earlier publications, in the present analysis the energy of the incident particle is fully taken into account. For one propagating mode, N=1 , we have been able to solve the diffusion equation for a number of particular observables, and the solution is in excellent agreement with the results of microscopic calculations. In general, we have not succeeded in finding a solution of the diffusion equation. We have thus developed a numerical simulation, to be called "random walk in the transfer matrix space," in which the universal statistical properties of a "building block" are first implemented numerically, and then the various building blocks are combined to find the statistical properties of the full waveguide. The reported results thus obtained (in which use was made of a "short-wavelength approximation") are in very good agreement with those arising from truly microscopic calculations, for both bulk and surface disorder. Since the paper has a clear pedagogical aim, we have included, for the benefit of experts and non-experts, a number of appendixes that contain the more involved calculations.

Effect of smoking on failure of H. pylori therapy and gastric histology in a high gastric cancer risk area of Colombia.

It has been proposed that eradication of Helicobacter pylori infection is a sound strategy for gastric cancer prevention. Several factors including smoking have been associated to treatment failure rates. This study aimed to evaluate the smoking effect on the efficacy of H. pylori therapy, as well as on the histological parameters in the gastric mucosa from subjects from a high gastric cancer risk area. Two-hundred-sixty-four Colombian subjects with gastric precancerous lesions who participated in a chemoprevention trial, received anti-H. pylori treatment at baseline and had data recorded on cigarette use, were included in this study. A detailed histopathological assessment of the gastric mucosa was performed in biopsies taken before any intervention. H. pylori eradication was assessed in gastric biopsies at 36 months post-treatment. The overall eradication rate was 52.3%; rates of 41.3% and 57.1% were observed for active-smokers and non-smokers, respectively. Multivariate logistic regression analysis showed that smokers had a 2-fold higher probability of failure in Helicobacter pylori eradication than non-smokers (OR: 2.0; 95% CI: 1.01-3.95). At baseline, active-smokers had a higher score of intestinal metaplasia compared to non-smokers. In the corpus mucosa, active-smokers showed lower scores of H. pylori density, total inflammation, neutrophil infiltration, and mucus depletion than non-smokers. In the antrum, no significant differences were observed between active-smokers and non-smokers. In summary, in patients who smoked, H. pylori treatment was less effective. Smoking cessation may benefit H. pylori eradication rates.

Effect of smoking on failure of H. pylori therapy and gastric histology in a high gastric cancer risk area of Colombia / Efecto del tabaquismo en la falla al tratamiento anti-H. pylori y en la histología gástrica en una zona de alto riesgo de cáncer gástrico en Colombia

It has been proposed that eradication of Helicobacter pylori infection is a sound strategy for gastric cancer prevention. Several factors including smoking have been associated to treatment failure rates. This study aimed to evaluate the smoking effect on the efficacy of H. pylori therapy, as well as on the histological parameters in the gastric mucosa from subjects from a high gastric cancer risk area. Two-hundred-sixty-four Colombian subjects with gastric precancerous lesions who participated in a chemoprevention trial, received anti- H. pylori treatment at baseline and had data recorded on cigarette use, were included in this study. A detailed histopathological assessment of the gastric mucosa was performed in biopsies taken before any intervention. H. pylori eradication was assessed in gastric biopsies at 36 months post-treatment. The overall eradication rate was 52.3%; rates of 41.3% and 57.1% were observed for active-smokers and non-smokers, respectively. Multivariate logistic regression analysis showed that smokers had a 2-fold higher probability of failure in Helicobacter pylori eradication than non-smokers (OR: 2.0; 95% CI: 1.01-3.95). At baseline, activesmokers had a higher score of intestinal metaplasia compared to non-smokers. In the corpus mucosa, active-smokers showed lower scores of H. pylori density, total inflammation, neutrophil infiltration, and mucus depletion than non-smokers. In the antrum, no significant differences were observed between active-smokers and non-smokers. In summary, in patients who smoked, H. pylori treatment was less effective. Smoking cessation may benefit H. pylori eradication rates.

La erradicación del Helicobacter pylori ha sido propuesta como medida promisoria en la prevención del cáncer gástrico. Varios factores, incluyendo el tabaquismo, se asocian con la falla del tratamiento. El objetivo de este estudio fue evaluar el efecto del tabaquismo en la eficacia del tratamiento anti-H. pylori y en la histología gástrica en residentes de una zona de alto riesgo de cáncer gástrico. Este estudio incluyó 264 sujetos colombianos con lesiones gástricas preneoplásicas que participaron en un estudio de quimioprevención, recibieron tratamiento anti-H. pylori al ingreso, y proveyeron información sobre tabaquismo. Se realizó un detallado análisis histopatológico en las biopsias colectadas al ingreso. La erradicación de la infección fue evaluada en las biopsias gástricas a los 36 meses post-tratamiento. El porcentaje general de erradicación fue de 52.3%, con proporciones de 41.3% y 57.1% en fumadores activos y no fumadores, respectivamente. El análisis de regresión logística múltiple mostró que el riesgo de presentar falla al tratamiento fue doble en fumadores en comparación con los no fumadores (OR: 2.0; 95% CI: 1.01-3.95). Los fumadores presentaron un mayor índice de metaplasia intestinal comparado con los no fumadores. En la mucosa del cuerpo gástrico los fumadores mostraron menores índices de colonización por H. pylori, inflamación total, infiltración de neutrófilos y depleción de moco que los no fumadores. En el antro no se observaron diferencias significacomtivas entre ambos grupos. En conclusión, el tratamiento anti-H. pylori fue menos efectivo en sujetos fumadores. La cesación del consumo de tabaco puede beneficiar las tasas de erradicación del H. pylori.

Age at acquisition of Helicobacter pylori infection: comparison of two areas with contrasting risk of gastric cancer.

BACKGROUND: Helicobacter pylori infection is usually acquired during childhood and is a known risk factor for the development of gastric malignancies in adulthood. It has been reported that early age at first infection may determine a neoplastic outcome in adults. The purpose of this study was to determine the prevalence of Helicobacter pylori infection in children residing in areas with high (Pasto) and low risk (Tumaco) of gastric cancer in Colombia to evaluate whether differences in the age of acquisition of H. pylori infection were present in the two populations. MATERIALS AND METHODS: The study sample was based on a census taken in 1999. Using the (13)C-urea breath test, we compared the prevalence of H. pylori infection among children aged 1-6 years. RESULTS: Among 345 children in Pasto, 206 (59.7%) were H. pylori-positive, compared with 188 (58.6%) among 321 children in Tumaco. The two populations share a common pattern of very early age at infection and marked increase in prevalence during the first 4 years of life. No differences in any one year were observed when comparing the two groups. CONCLUSIONS: The prevalence of infection was similarly high and increased with age in both populations. In these populations the age of acquisition of H. pylori after 1 year of age does not appear to be a primary factor responsible for the differences in the rates of gastric cancer incidence in adults. Previous findings in adults showed lower prevalence of the most virulent genotypes in Tumaco compared to Pasto, and bacterial virulence may play a key role in determining cancer outcome.

[The factors associated with noncompliance with antimalarial treatment in Ecuadorian patients]. / Factores asociados con el incumplimiento del tratamiento antipalúdico en pacientes ecuatorianos.

A total of 249 persons living in the northwest part of Ecuador with a clinical diagnosis of malaria confirmed by thick blood films were treated with chloroquine and primaquine according to the therapeutical system in force in the National Service for Eradication of Malaria. New clinical assessment and thick blood film were applied after 4 days in P. falciparum (n = 120) cases and after 8 days in P. vivax (n = 129) cases; patients were questioned about the compliance or non-compliance with the treatment, and the reasons for their acting in either way were studied. EPI-INFO 6.04 and SPSS PC 7.0 packages served to process the information: "kind adjustment test" (bondad de ajuste) abd factorial analysis of correspondences were used. The patient who daily took his/her pills for the number of days indicated, at the established intervals and at the right time was defined as a patient complying with the drug therapy. For every 3 patients complying with treatment, there were 2 who did not; non-compliance was not significantly related to age, sex, educational level, ethnic group, urban or rural setting or level of income, but learning about seriousness of the infection did help to compliance with the therapy. The reasons for non-compliance were mainly associated with drugs (side effects/reluctancy to take drugs), with the fact of forgetting to take them and of "getting cured quickly". The profile of the patient who did not comply with treatment corresponded to male, teenager, mixed race, poor and rural setting.

The role of proliferating cell nuclear antigen (PCNA) in predicting biologic behavior of lymphoid infiltrates of the orbit and ocular adnexae.

The authors performed a retrospective clinicopathologic review of lymphoid tumors of the orbit and ocular adnexa. In addition, we used an immunohistologic marker for proliferating cell nuclear antigen (PCNA), an intranuclear protein with greatest expression in actively proliferating (dividing) cells, to determine whether levels of PCNA can be correlated with the presence or future development of systemic lymphoma. To the authors' knowledge, the present study represents the first in which PCNA indices, i.e., the number of cells that showed diffuse intranuclear staining for PCNA averaged per 10 high power field (HPF), were correlated with systemic disease in orbital and ocular adnexal lymphomas. The percentage of B- and T-cells in the tumor infiltrate was also determined. Followup data showed that two patients with eyelid involvement had preexisting systemic lymphoma, whereas another with bilateral lacrimal gland disease later developed systemic lymphoma. Followup times ranged from 24 to 42 months (mean 39.7 months). The mean PCNA level in three patients with systemic disease was 13.3 and in the six patients with no systemic disease was 33.8. These results suggest that PCNA alone cannot be used as a marker for the presence of, or development into, systemic lymphoma.

Cáncer del tubo digestivo en el Hospital Carlos Andrade Marín / Cancer of the alimentary canal in the Hospital Carlos Andrade Marín

Analiza los datos de 1285 pacientes diagnosticados y tratados en el Hospital Carlos Andrade Marín del IESS, con tumores malignos del tubo digestivo, durante un período de 10 años comprendidos entre 1985 y 1994 y captados por el Registro Nacional de Tumores de SOLCA-Quito. Se encuentran interesantes diferencias con los datos de la población general de Quito y de otros registros de cáncer, por ser la población analizada una muestra escogida de personas aseguradas y también se observan diferencias relacionadas con el sexo y con la edad de los pacientes. El cáncer gástrico es el tumor más frecuente en el grupo constituyendo el 64.4xciento de los tumores del tubo digestivo y el 13.7xciento de todas las neoplasias malignas manejadas en el Hospital. Los tumores del tracto digestivo superior son más frecuentes en hombres, mientras que los de colon lo son en mujeres y en éstas se presentan además en edades más tempranas...

The role of proliferating cell nuclear antigen (PCNA) in differentiating idiopathic orbital inflammatory disease and lymphoid proliferations.

The purpose of the present study was to determine whether proliferating cell nuclear antigen (PCNA), an immunohistochemical marker for a nuclear protein abundant in actively proliferating (dividing) cells, is useful as an aid in differentiating idiopathic orbital inflammatory syndrome (IOIS) from lymphoproliferative lesions (LLs). Records of all patients with IOIS and LLs were studied retrospectively. Tissue biopsy specimens from four patients with IOIS and nine patients with LLs were examined. The diagnosis in each case was based on presenting signs and symptoms, orbital computed tomography (CT) and/or magnetic resonance (MR) scans, histopathologic criteria, and follow-up data consistent with the entity. These findings were correlated with the percentage of B- and T-cells in the lesions as well as with the number of cells that demonstrated staining for PCNA in formalin-fixed tissue. PCNA activity was markedly increased in the higher grade (HG) lymphoma group as compared to that in the low grade (LG) lymphoma and idiopathic inflammatory group. Lymphoma cases showed a significantly increased B-/T-cell ratio compared to IOIS lesions. PCNA activity in conjunction with the ratio of B-/T-cells may be a helpful immunohistologic adjunct for differentiating purely inflammatory lesions of the orbit from lymphoid tumors. Further studies are necessary to compare PCNA activity in fresh frozen tissue with that in formalin-fixed tissue.