High jugular bulb with a diverticulum and vestibular aqueduct dehiscence: an anatomical variant to be aware in patients with hearing loss

PURPOSE

To describe an anatomical variant that should be consider in patients with hearing loss.

METHODS

An 8-year-old girl underwent to temporal bone computed tomography for the evaluation of bilateral conductive hearing loss and further assessment of possible enlarged vestibular aqueduct or high jugular bulb on brain magnetic resonance imaging (MRI).

RESULTS

CT of temporal bone showed a cystic cavity with bony sclerotic margins extending from the right jugular foramen to the vestibular aqueduct. Bony dehiscence of the jugular foramen with the right carotid canal was also noted. On brain MRI, there was no evidence of enlargement of the endolymphatic duct and sac on T2 thin-section gradient echo sequence. Time of flight MR angiography did not show arterial flow in the cavity. Contrast enhanced MR venography confirmed the presence of a high right jugular bulb with a diverticulum extending into the vestibular aqueduct due to jugular bulb-vestibular aqueduct dehiscence.

CONCLUSION

Knowledge of high jugular bulb-vestibular aqueduct dehiscence is important in the assessment of patients with otologic symptoms such as vertigo, tinnitus and hearing loss.

Análisis filogenético del gen Spike del virus de la diarrea epidémica porcina en Colombia, 2014-2015

Se reportaron brotes de diarrea epidémica porcina en Colombia durante 2014-2015. En el presente análisis, se descargaron secuencias de nucleótidos completas del Genbank para el gen Spike de las cepas del virus de la diarrea epidémica porcina (PEDV) reportadas en Colombia. En el árbol filogenético basado en proteínas de espiga de PEDV, las cepas de Colombia se agruparon en los genotipos G2a y S-INDEL, las cepas mostraron alta homología (> 99,9%) con cepas de Estados Unidos (Colorado / 2013, OH851), como así como inserciones y deleciones en el dominio S1 del gen Spike presente tanto en cepas colombianas como en cepas de referencia. Se han identificado varias sustituciones de aminoácidos en los epítopos neutralizantes de las cepas colombianas en comparación con la cepa de referencia CV777. Estos estudios podrían ayudar a rastrear las posibles rutas de introducción del PEDV en Colombia, reconocer las relaciones filogenéticas de las cepas que circulan en el país e implementar estrategias de control y prevención.

Evaluation of the impact of pre- and post-harvest maize handling practices on mycotoxin contamination on smallholder farms in Guatemala

Mycotoxins are secondary metabolites produced by fungi including Aspergillus and Fusarium that commonly contaminate crops, such as maize, resulting in economic losses and food insecurity. Mycotoxins can contaminate crops during pre- and post-harvest stages. Consumption of mycotoxin-contaminated foods has been linked to a variety of negative health outcomes including liver cancer, stunting, and neural tube defects. In countries such as Guatemala where maize constitutes a major portion of the diet, mycotoxins can be a significant contributor to disease burden. This review describes maize pre- and post-harvest practices in Guatemala that can lead to the development of mycotoxins and subsequent exposure to humans and animals, current information gaps, and opportunities for future research. There are specific challenges to minimising fungal growth and subsequent mycotoxin production during storage of maize in Guatemala, including reducing moisture content, minimising pest damage, and controlling temperature. Research on maize-handling practices that are associated with the greatest mycotoxin exposure in Guatemala is needed to prioritise allocation of resources and reduce exposure.

Reliability and accuracy of individual Alberta Stroke Program Early CT Score regions using a medical and a smartphone reading system in a telestroke network

Introduction

The aim of this study was to assess individual regions of the Alberta Stroke Program Early CT Score in noncontrast head computed tomography interpretations using a smartphone in a telestroke network, by comparison to a medical monitor.

Methods

The review board of our institution approved this retrospective study. A factorial design with 188 patients, four radiologists and two reading systems was used. Accuracy and reliability were evaluated.

Results

Very good interobserver agreements were observed on the total Alberta Stroke Program Early CT Score for both the medical and smartphone reading systems, with intraclass correlation coefficients of 0.91 and 0.84 respectively. Interobserver agreements were moderate to very good for the medical reading system (all intraclass correlation coefficients >0.74), whereas they were fair to very good for the smartphone (intraclass correlation coefficients ranged from 0.31–0.81). All intraobserver agreements were good (intraclass correlation coefficient >0.64), except for internal capsule (0.48) and M2 (0.55) regions. The areas under the receiver-operating curve ranged from 0.69–0.89 for the medical system, while for the smartphone ranged from 0.44–0.86. No statistical differences were observed between medical and smartphone reading systems for each region (all p > 0.05).

Discussion

If radiologists are better trained in the evaluation of the lesions in the insula, the internal capsule and the M2 regions, the total and the dichotomised Alberta Stroke Program Early CT Score will be more precise. Hence, ruling out contraindications to thrombolysis administration will be improved, allowing assessment of head computed tomography in a telestroke network using a smartphone to be a common practice.

High prevalence of non-alcoholic fatty liver disease and metabolic risk factors in Guatemala: A population-based study

BACKGROUND

There are no data on the prevalence of non-alcoholic fatty liver disease (NAFLD) in general population samples in Guatemala or in other Central American countries. The prevalence and distribution of NAFLD and its associated risk factors were evaluated in a population-based sample of adults in Guatemala.

METHODS

Cross-sectional study of 411 men and women 40 years of age or older residing in urban and rural areas of Guatemala. Metabolic outcomes included obesity, central obesity, hypercholesterolemia, diabetes, and metabolic syndrome (MetS). Liver disease outcomes included elevated liver enzymes, elevated Fatty Liver Index (FLI), and elevated FIB-4 score.

RESULTS

The overall prevalence of obesity, central obesity, diabetes, and MetS were 30.9, 74.3, 21.6, and 64.2%, respectively. The fully-adjusted prevalence ratios (95% CI) for obesity, central obesity, diabetes, and MetS comparing women to men were 2.83 (1.86-4.30), 1.72 (1.46-2.02), 1.18 (1.03-1.34), and 1.87 (1.53-2.29), respectively. The overall prevalence of elevated liver enzymes (ALT or AST), elevated FLI, and elevated FIB-4 scores were 38.4, 60.1, and 4.1%, respectively. The fully-adjusted prevalence ratios (95% CI) for elevated liver enzymes (either ALT or AST) and elevated FLI score comparing women to men were 2.99 (1.84-4.86) and 1.47 (1.18-1.84), respectively.

CONCLUSIONS

The prevalence of metabolic abnormalities and liver outcomes in this general population study was very high. The prevalence of metabolic and liver abnormalities was particularly high among women, an observation that could explain the atypical 1:1 male to female ratio of liver cancer in Guatemala.

Abstract 03: Imaging characteristics of head and neck tumors according to human papillomavirus (HPV) status in Bogotá, Colombia

Background: HPV-positive head and neck tumors (HNT) correspond to a unique entity given their clinical behavior and molecular characteristics. These tumors can show distinct features on pretreatment imaging, such as well-defined borders and cystic nodal metastases; therefore, the aim of our study was to evaluate the imaging characteristics and determine if there are differences between HPV-positive and HPV-negative HNT tumors in patients studied at our institution.

Design: A retrospective pretreatment imaging review from 35 HNT cases recruited under INTERCHANGE- IARC project in Latin America between 11-2014 and 12-2016 was performed. Imaging evaluation included primary lesion and nodal metastases. Initial evaluation by radiologists was blinded for patients' histological findings and HPV status. Radiology was evaluated for: location, tumor size, tumor border morphology, contrast enhancement, nodal metastases, size of metastasis and morphology of nodal metastasis. Radiological findings were correlated with histology and p16 INK4a inmunohistochemistry using clone E6H4 (HPV surrogate marker).

Results: Pretreatment images were available for review only in 17 of 35 cases (48,5%). 10 cases had computerized tomography (CT) examination, 1 case magnetic resonance (MR) and 6 cases had 18F-FDG PET-CT. 6/17 cases (35.3%) were excluded due to no visualization of the primary tumor or due to limitation artifacts (amalgam). From the 11 cases available for review, 7 were from the oropharynx (OP), 2 from the oral cavity (OC) and 1 from the larynx (LA). All OP tumors were positive for p16 and all the rest tumors were p16 negative. Tumor size ranged from 7 to 51 mm in greatest dimension. Well-defined borders were present in 4/7 p16 positive tumors vs 2/4 p16 negative tumors. Tumor enhancement with contrast was present and able to evaluate only in 5 out of 11 tumors (3 p16 + and 2 p16 -). All the OP p16 positive tumors presented with nodal metastasis greater than 10 mm in dimension. 6/7 had nodal cystic change and these p16 positive cases were more likely to have large cystic nodal metastases with a cystic component larger than 50% of the nodal size (6/7) than p16/HPV negative tumors (1 out of 4 cases had smaller nodal metastasis with cystic component <50%).

Conclusion: Large nodal metastasis (>10 mm) with cystic component larger than 50% of the node size is an important finding seen in p16 HNT. One should consider these findings when examining neck images in patients with unknown primary in order to exclude malignancy given that usually cystic nodes could be misdiagnosed as benign. Our nondiagnostic imaging rate pretreatment was 35%; in order to improve the use of diagnostic tools we recommend the use of MR especially in patients with amalgams and/or tumor located at the oral cavity and oropharynx. Further studies are granted with a larger sample size in order to validate and confirm imaging characteristics in p16/HPV positive HNT.

Citation Format: Nicolás Useche, Oscar Torres, Maria M. Rojas, Mauricio Palau-Lázaro, Marcela Mejía-Arango, Ana Margarita Baldión, José A. Hakim, Johanna Campos, Alberto Escallon, Aylen Vanessa Ospina, Sandra Perdomo, Paula A. Rodríguez-Urrego. Imaging characteristics of head and neck tumors according to human papillomavirus (HPV) status in Bogotá, Colombia [abstract]. In: Proceedings of the AACR-AHNS Head and Neck Cancer Conference: Optimizing Survival and Quality of Life through Basic, Clinical, and Translational Research; April 23-25, 2017; San Diego, CA. Philadelphia (PA): AACR; Clin Cancer Res 2017;23(23_Suppl):Abstract nr 03.

Linking hepatitis C virus infection to pre-1994 blood transfusions in female patients

INTRODUCTION

Most blood transfusions occur in female patients. The introduction of serologic screening practices by blood banks reduced the transfusion-related rate of infection with hepatitis C virus (HCV). In Mexico patients with pre-1994 transfusion history are at high risk of being detected with HCV infection. We aimed at establishing an interrelationship between two variables: pre-1994 transfusion history and rate of infection in women treated in the Guadalajara Metropolitan Area hospitals, in Mexico.

METHODS

Analytical observational case-control study which included both non-infected women and patients diagnosed with hepatitis C virus infection, in whom the pre-1994 transfusion history was determined. The cases were 150 women with confirmed hepatitis C virus serologic diagnosis. The controls were 150 women whose hepatitis C virus-detection serologic tests had yielded negative results.

RESULTS

An odds ratio of 9.07 (95% CI: 5.37 – 15.3; p< 0.001) was found where the rate of infection for the case group was 0.72 while the control group had a ratio of 0.22; population attributable risk (PAR) was 0.64 (95% CI: 0.53 – 0.73), while etiologic fraction was 0.88 (95% CI: 0.81 – 0.93).

CONCLUSIONS

Among women, having been exposed to pre-1994 blood transfusion means a risk 9.07 times higher than not being exposed to blood transfusion in the same time frame.

Tropospheric Emissions: Monitoring of Pollution (TEMPO)

TEMPO was selected in 2012 by NASA as the first Earth Venture Instrument, for launch between 2018 and 2021. It will measure atmospheric pollution for greater North America from space using ultraviolet and visible spectroscopy. TEMPO observes from Mexico City, Cuba, and the Bahamas to the Canadian oil sands, and from the Atlantic to the Pacific, hourly and at high spatial resolution (~2.1 km N/S×4.4 km E/W at 36.5°N, 100°W). TEMPO provides a tropospheric measurement suite that includes the key elements of tropospheric air pollution chemistry, as well as contributing to carbon cycle knowledge. Measurements are made hourly from geostationary (GEO) orbit, to capture the high variability present in the diurnal cycle of emissions and chemistry that are unobservable from current low-Earth orbit (LEO) satellites that measure once per day. The small product spatial footprint resolves pollution sources at sub-urban scale. Together, this temporal and spatial resolution improves emission inventories, monitors population exposure, and enables effective emission-control strategies. TEMPO takes advantage of a commercial GEO host spacecraft to provide a modest cost mission that measures the spectra required to retrieve ozone (O3), nitrogen dioxide (NO2), sulfur dioxide (SO2), formaldehyde (H2CO), glyoxal (C2H2O2), bromine monoxide (BrO), IO (iodine monoxide),water vapor, aerosols, cloud parameters, ultraviolet radiation, and foliage properties. TEMPO thus measures the major elements, directly or by proxy, in the tropospheric O3 chemistry cycle. Multi-spectral observations provide sensitivity to O3 in the lowermost troposphere, substantially reducing uncertainty in air quality predictions. TEMPO quantifies and tracks the evolution of aerosol loading. It provides these near-real-time air quality products that will be made publicly available. TEMPO will launch at a prime time to be the North American component of the global geostationary constellation of pollution monitoring together with the European Sentinel-4 (S4) and Korean Geostationary Environment Monitoring Spectrometer (GEMS) instruments.

Estudio preliminar de la diversidad genética de perros con fenotipo Poodle en Colombia usando microsatélites

El objetivo de este estudio fue estimar la variabilidad genética de una muestra poblacional de perros con fenotipo Poodle en Bogotá - Colombia. La variabilidad genética de 81 perros con fenotipo Poodle se estudió mediante el genotipado de cinco loci de microsatélites. La heterocigosidad esperada (HE) para los loci: AHTK253, CXX279, INU030, INU055 y REN162C04 fue de 0,747, 0,788, 0,767, 0,679 y 0,751, respectivamente. La HE para el conjunto de la población fue de 0,746. La población de Poodles analizada tuvo una alta diversidad genética y se encontró que no existe una subestructuración poblacional, hecho que desvía el equilibrio HW; con lo que demuestra que la población de Poodle colombiana sea una perfecta candidata para estudios de asociación genética, y de conservación de la biodiversidad de los animales domésticos.

Influence of ethnicity on the distribution of genetic polymorphisms associated with risk of chronic liver disease in South American populations

BACKGROUND

The global burden of chronic liver disease is rising. Besides environmental, behavioral, viral and metabolic factors, genetic polymorphisms in patatin-like phospholipase-3 (PNPLA3) and vitamin D receptor (VDR) genes have been related to the development of chronic liver disease and progression towards liver cancer. Although their prevalence differs remarkably among ethnic groups, the frequency of these polymorphisms in South American populations -whose genetic background is highly admixed- has been poorly studied. Hence, the aim of this study was to characterize polymorphisms related to chronic liver disease and their association with the genetic ancestry of South American populations.

RESULTS

DNA samples from 258 healthy unrelated male volunteers were analyzed. The frequencies of G and C alleles of rs738409 polymorphism (PNPLA3 gene) were 74 % and 26 %, respectively; whereas the bAt (CCA) haplotype (VDR gene) was observed in 32.5 % of the samples. The GG genotype of PNPLA3 rs738409 and the bAt (CCA) haplotype -associated with an increased risk of chronic liver disease and progression towards liver cancer- were significantly more frequent among samples exhibiting maternal and paternal Native American haplogroups (63.7 % and 64.6 %), intermediate among admixed samples (45.1 % and 44.9 %; p = 0.03) and the lowest for Non-native American ancestry (30.1 % and 29.6 %; p = 0.001 and p = 0.0008).

CONCLUSIONS

These results suggest that individuals with Native American ancestry might have a high risk of chronic liver disorders and cancer. Furthermore, these data not only support the molecular evaluation of ancestry in multi-ethnic population studies, but also suggest that the characterization of these variants in South American populations may be useful for establishing public health policies aimed at high risk ethnic communities.

Human health implications from co-exposure to aflatoxins and fumonisins in maize-based foods in Latin America: Guatemala as a case study

Co-occurrence of fumonisin B1 (FB1) and aflatoxin B1 (AFB1) in maize has been demonstrated in many surveys. Combined-exposure to FB1 and AFB1 was of concern to the Joint FAO/WHO Expert Committee on Food Additives because of the known genotoxicity of AFB1 and the ability of FB1 to induce regenerative proliferation in target tissues. Humans living where maize is a dietary staple are at high risk for exposure to both mycotoxins. Our work has focused on Guatemala, a country in Central America where maize is consumed in large amounts every day and where intake of FB1 has been shown to be potentially quite high using biomarker-based studies. In 2012 a survey was conducted which analysed maize samples for FB1 and AFB1 from all 22 departments of Guatemala. The results show that the levels of AFB1 exposure are also potentially quite high in Guatemala, and likely throughout Central America and Mexico. The implications of co-exposure for human health are numerous, but one area of particular concern is the potential of FB1 to modulate AFB1 hepatoxicity and/or hepatocarcinogenicity. Both the mechanism of action of FB1 and its ability to promote liver carcinogenicity in rats and rainbow trout is consistent with this concern. In farm and laboratory animals FB1 inhibits ceramide synthases, key enzymes in de novo ceramide biosynthesis. The inhibition of sphingolipid signalling pathways mediating programmed cell death and activation of pathways stimulating cell proliferation in livers of individuals exposed to AFB1 could contribute to the tumorigenicity of AFB1. Studies investigating the health effects of either toxin should consider the potential for co-exposure to both toxins. Also, in countries where maize-based food are prepared by alkaline treatment of the maize kernels, the effect of traditional processing on AFB1 levels and toxicity needs to be determined, especially for maize highly contaminated with AFB1.

Adjuvants for vaccines to drugs of abuse and addiction

Immunotherapeutic vaccines to drugs of abuse, including nicotine, cocaine, heroin, oxycodone, methamphetamine, and others are being developed. The theoretical basis of such vaccines is to induce antibodies that sequester the drug in the blood in the form of antibody-bound drug that cannot cross the blood brain barrier, thereby preventing psychoactive effects. Because the drugs are haptens a successful vaccine relies on development of appropriate hapten-protein carrier conjugates. However, because induction of high and prolonged levels of antibodies is required for an effective vaccine, and because injection of T-independent haptenic drugs of abuse does not induce memory recall responses, the role of adjuvants during immunization plays a critical role. As reviewed herein, preclinical studies often use strong adjuvants such as complete and incomplete Freund's adjuvant and others that cannot be, or in the case of many newer adjuvants, have never been, employed in humans. Balanced against this, the only adjuvant that has been included in candidate vaccines in human clinical trials to nicotine and cocaine has been aluminum hydroxide gel. While aluminum salts have been widely utilized worldwide in numerous licensed vaccines, the experience with human responses to aluminum salt-adjuvanted vaccines to haptenic drugs of abuse has suggested that the immune responses are too weak to allow development of a successful vaccine. What is needed is an adjuvant or combination of adjuvants that are safe, potent, widely available, easily manufactured, and cost-effective. Based on our review of the field we recommend the following adjuvant combinations either for research or for product development for human use: aluminum salt with adsorbed monophosphoryl lipid A (MPLA); liposomes containing MPLA [L(MPLA)]; L(MPLA) adsorbed to aluminum salt; oil-in-water emulsion; or oil-in-water emulsion containing MPLA.

Distribution of genetic polymorphisms associated with hepatitis C virus (HCV) antiviral response in a multiethnic and admixed population

The prevalence of genetic polymorphisms identified as predictors of therapeutic-induced hepatitis C virus (HCV) clearance differs among ethnic groups. However, there is a paucity of information about their prevalence in South American populations, whose genetic background is highly admixed. Hence, single-nucleotide polymorphisms rs12979860, rs1127354 and rs7270101 were characterized in 1350 healthy individuals, and ethnicity was assessed in 259 randomly selected samples. The frequency of rs12979860CC, associated to HCV treatment response, and rs1127354nonCC, related to protection against hemolytic anemia, were significantly higher among individuals with maternal and paternal Non-native American haplogroups (64.5% and 24.2%), intermediate among admixed samples (44.1% and 20.4%) and the lowest for individuals with Native American ancestry (30.4% and 6.5%). This is the first systematic study focused on analyzing HCV predictors of antiviral response and ethnicity in South American populations. The characterization of these variants is critical to evaluate the risk-benefit of antiviral treatment according to the patient ancestry in admixed populations.

Fumonisin biomarkers in maize eaters and implications for human disease

Maize is the predominant food source contaminated by fumonisins and this has particular health risks for communities consuming maize as a staple diet. The main biochemical effect of fumonisins is the inhibition of ceramide biosynthesis causing an increase in sphingoid bases and sphingoid base 1-phosphates and a depletion of the complex sphingolipids, thereby disrupting lipid metabolism and sphingolipid-mediated processes and signalling systems. Attempts to use the elevation of sphinganine as a human biomarker of fumonisin exposure have to date been unsuccessful. Consequently, recent research has focussed on developing a urinary exposure biomarker based on the measurement of the nonmetabolised toxin. In animals, fumonisins are poorly absorbed in the gut and are mostly excreted unmetabolised in faeces, with only a small percentage (0.25-2.0%) in urine. This appears to also be true in humans were fumonisin B1 (FB1) is detectable in urine soon after exposure, but in very small amounts relative to total intake. However, with modern sensitive and selective analytical methods such as liquid chromatography-tandem mass spectrometry, these low levels can be readily determined. The first study to show a positive correlation between consumption of maize and urinary FB1 was conducted in a Mexican population consuming tortillas as a staple food. Further validation of this relationship was achieved in a South African subsistence farming community with a positive correlation between urinary FB1 and fumonisin exposure, as assessed by food analysis and food intake data. The most recent developments are aimed at measuring multiple mycotoxin biomarkers in urine, including FB1. Current exposure studies in Guatemala are combining the urinary biomarker with measurement of sphinganine-1-phosphate in blood spots as a measure of biochemical effect. Thus, the urinary FB1 biomarker could contribute considerably in assessing the adverse health impact of fumonisin exposure.