Reading performance is not affected by a prism induced increase of horizontal and vertical vergence demand

PURPOSE Dyslexia is the most common developmental reading disorder that affects language skills. Latent strabismus (heterophoria) has been suspected to be causally involved. Even though phoria correction in dyslexic children is commonly applied, the evidence in support of a benefit is poor. In order to provide experimental evidence on this issue, we simulated phoria in healthy readers by modifying the vergence tone required to maintain binocular alignment. METHODS Vergence tone was altered with prisms that were placed in front of one eye in 16 healthy subjects to induce exophoria, esophoria, or vertical phoria. Subjects were to read one paragraph for each condition, from which reading speed was determined. Text comprehension was tested with a forced multiple choice test. Eye movements were recorded during reading and subsequently analyzed for saccadic amplitudes, saccades per 10 letters, percentage of regressive (backward) saccades, average fixation duration, first fixation duration on a word, and gaze duration. RESULTS Acute change of horizontal and vertical vergence tone does neither significantly affect reading performance nor reading associated eye movements. CONCLUSION Prisms in healthy subjects fail to induce a significant change of reading performance. This finding is not compatible with a role of phoria in dyslexia. Our results contrast the proposal for correcting small angle heterophorias in dyslexic children.

First thoughts on surface tonal patterns in Amawaka, a Panoan language of Peru and Brazil

Amawaka ([ɑmɨ̃ˈwɐkɑ]) is a highly endangered and underdocumented tonal language of the Headwaters (Fleck 2011) subgroup of the Panoan family in the Southwest Amazon Basin, spoken by approximately 200 people. Undocumented phonetic and phonological phenomena of Amawaka include its tonal structure, both in terms of surface realizations and the patterns underlying these realizations. Original audiovisual data from the author’s fieldwork in various Amawaka communities at the Peru-Brazil border will illuminate the as-yet obscure tonal systematicity of the language. Unlike other elements, monosyllabic bimoraic phonological nominal words with long vowels display variation in their surface realization. All the words with the open back unrounded /ɑ/, like /ˈkɑ̀:/ (patarashca, a traditional Amazonian dish), /ˈnɑ̀:/ “mestizo” etc. [with the exception of /ˈtɑ:/ “reed”, which surfaces with either a H or L tone] bear a low tone in isolation. This realization contrasts with all the encountered nominal monosyllables with vowels from the close and close-mid front and central spectrum /i, ɘ, ɨ, ɨ̃/, which clearly surface as high tone words in isolation, for example /ˈmɨ̃́:/ (a clay-lick for animals), /ˈwí:/ “Anopheles, spp. mosquito”. Monosyllables with close-mid back rounded /o/ have a less restrictive pitch that varies among speakers from low to high realizations, and sometimes even across the speech tokens from an individual speaker, e.g. /wó:/ or /wō:/ “hair”, /ɧō:/ or /ɧò:/ (a type of tarantula). Phrasal tonal phonology is more complex, when these three kinds of monosyllables appear in larger noun phrases. Some retain the same surface tones as their isolation form, while others seem to vary freely in their surface realization, e.g. /ˈtɘ́:.nɑ̀:/ or /ˈtɘ́:.nɑ́:/ ‘one mestizo’. Yet other monosyllables, e.g. /mɑ̀:/, exhibit a falling tone when preceded by a H syllable, suggesting probably latent tone sandhi phenomena, e.g /ˈtɘ́:.mɑ̂:/ (one clay-lick for parrots). In disyllabic, trisyllabic and quadrisyllabic nouns, tonal and stress patterns generally seem to be more consistent and tend to be retained both in isolation and in larger intonational phrases. Disyllabic nouns, for instance, surface as L-H or L-L when a glottal stop is in coda position. The association of L with a glottal stop is a feature that occurs in other Panoan languages as well, like Capanahua (Loos 1969), and more generally it is an areal feature, found in other parts of Amazonia (Hyman 2010). So, tone has significant interactions with the glottal stop and glottalization, which generally co-occurs with L. The data above suggest that the underlying tonal system of Amawaka is much more complex than the privative one-tone analysis (/H/ vs. Ø, i.e. lack of tone) that was proposed by Russell and Russell (1959). Evidence from field data suggests either an equipollent (Hyman 2010) two-tone opposition between /H/ and /L/, or a hybrid system, with both equipollent and privative features; that is, /H/ vs. /L/ vs. either Ø or /M/. This first systematic description of Amawaka tone, in conjunction with ongoing research, is poised to address broader questions concerning interrelationships between surface/underlying tone and other suprasegmental features, such as nasality, metrical stress, and intonation. References Fleck, David W. 2011. Panoan languages and linguistics. In Javier Ruedas and David W. Fleck (Eds.), Panoan Histories and Interethnic Identities, To appear. Hyman, Larry. 2010. Amazonia and the typology of tone systems. Presented at the conference Amazonicas III: The structure of the Amazonian languages. Bogotá. Loos, Eugene E. 1969. The phonology of Capanahua and its grammatical basis. Norman: SIL and U. Oklahoma. Russell, Robert & Dolores. 1959. Syntactotonemics in Amahuaca (Pano). Série Lingüistica Especial, 128-167. Publicaçoes do Museu Nacional, Rio de Janeiro, Brasil.

Towards an analysis of tonal patterns in Amawaka, a Panoan language of Peru and Brazil

Amawaka ([ɑmɨ̃ˈwɐkɑ]) is a highly endangered and underdocumented tonal language of the Headwaters (Fleck 2011) subgroup of the Panoan family in the Southwest Amazon Basin, spoken by approximately 200 people. Undocumented phonetic and phonological phenomena of Amawaka include its tonal structure, both in terms of surface realizations and the patterns underlying these realizations. Original audiovisual data from the author’s fieldwork in various Amawaka communities at the Peru-Brazil border will illuminate the as-yet obscure tonal systematicity of the language. Unlike other elements, monosyllabic bimoraic phonological nominal words with long vowels display variation in their surface realization. All the words with the open back unrounded /ɑ/, like /ˈkɑ̀:/ (a traditional Amazonian dish), /ˈnɑ̀:/ “mestizo” etc. [with the exception of /ˈtɑ:/ “reed”, which surfaces with either a H or L tone] bear a low tone in isolation. This realization contrasts with all the encountered nominal monosyllables with vowels from the close and close-mid front and central spectrum /i, ɘ, ɨ, ɨ̃/, which clearly surface as high tone words in isolation, for example /ˈmɨ̃́:/ (a clay-lick for animals), /ˈwí:/ “Anopheles, spp. mosquito”. Monosyllables with close-mid back rounded /o/ have a less restrictive pitch that varies among speakers from low to high realizations, and sometimes even across the speech tokens from an individual speaker, e.g. /wó:/ or /wō:/ “hair”, /ɧō:/ or /ɧò:/ (a type of tarantula). Phrasal tonal phonology is more complex, when these three kinds of monosyllables appear in larger noun phrases. Some retain the same surface tones as their isolation form, while others seem to vary freely in their surface realization, e.g. /ˈtɘ́:.nɑ̀:/ or /ˈtɘ́:.nɑ́:/ ‘one mestizo’. Yet other monosyllables, e.g. /mɑ̀:/, exhibit a falling tone when preceded by a H syllable, suggesting probably latent tone sandhi phenomena, e.g /ˈtɘ́:.mɑ̂:/ (one clay-lick for parrots). In disyllabic, trisyllabic and quadrisyllabic nouns, tonal and stress patterns generally seem to be more consistent and tend to be retained both in isolation and in larger intonational phrases. Disyllabic nouns, for instance, surface as L-H or L-L when a glottal stop is in coda position. The association of L with a glottal stop is a feature that occurs in other Panoan languages as well, like Capanahua (Loos 1969), and more generally it is an areal feature, found in other parts of Amazonia (Hyman 2010). So, tone has significant interactions with the glottal stop and glottalization, which generally co-occurs with L. The data above suggest that the underlying tonal system of Amawaka is much more complex than the privative one-tone analysis (/H/ vs. Ø, i.e. lack of tone) that was proposed by Russell and Russell (1959). Evidence from field data suggests either an equipollent (Hyman 2010) two-tone opposition between /H/ and /L/, or a hybrid system, with both equipollent and privative features; that is, /H/ vs. /L/ vs. either Ø or /M/. This first systematic description of Amawaka tone, in conjunction with ongoing research, is poised to address broader questions concerning interrelationships between surface/underlying tone and other suprasegmental features, such as nasality, metrical stress, and intonation. References Fleck, David W. 2011. Panoan languages and linguistics. In Javier Ruedas and David W. Fleck (Eds.), Panoan Histories and Interethnic Identities, To appear. Hyman, Larry. 2010. Amazonia and the typology of tone systems. Presented at the conference Amazonicas III: The structure of the Amazonian languages. Bogotá. Loos, Eugene E. 1969. The phonology of Capanahua and its grammatical basis. Norman: SIL and U. Oklahoma. Russell, Robert & Dolores. 1959. Syntactotonemics in Amahuaca (Pano). Série Lingüistica Especial, 128-167. Publicaçoes do Museu Nacional, Rio de Janeiro, Brasil.

Increased levels of choline metabolites are an early marker of docetaxel treatment response in BRCA1-mutated mouse mammary tumors: an assessment by ex vivo proton magnetic resonance spectroscopy.

BACKGROUND Docetaxel is one of the most frequently used drugs to treat breast cancer. However, resistance or incomplete response to docetaxel is a major challenge. The aim of this study was to utilize MR metabolomics to identify potential biomarkers of docetaxel resistance in a mouse model for BRCA1-mutated breast cancer. METHODOLOGY High resolution magic angle spinning (HRMAS) (1)H MR spectroscopy was performed on tissue samples obtained from docetaxel-sensitive or -resistant BRCA1-mutated mammary tumors in mice. Measurements were performed on samples obtained before treatment and at 1-2, 3-5 and 6-7 days after a 25 mg/kg dose of docetaxel. The MR spectra were analyzed by multivariate analysis, followed by analysis of the signals of individual compounds by peak fitting and integration with normalization to the integral of the creatine signal and of all signals between 2.9 and 3.6 ppm. RESULTS The HRMAS spectra revealed significant metabolic differences between sensitive and resistant tissue samples. In particular choline metabolites were higher in resistant tumors by more than 50% with respect to creatine and by more than 30% with respect to all signals between 2.9 and 3.6 ppm. Shortly after treatment (1-2 days) the normalized choline metabolite levels were significantly increased by more than 30% in the sensitive group coinciding with the time of highest apoptotic activity induced by docetaxel. Thereafter, choline metabolites in these tumors returned towards pre-treatment levels. No change in choline compounds was observed in the resistant tumors over the whole time of investigation. CONCLUSIONS Relative tissue concentrations of choline compounds are higher in docetaxel resistant than in sensitive BRCA1-mutated mouse mammary tumors, but in the first days after docetaxel treatment only in the sensitive tumors an increase of these compounds is observed. Thus both pre- and post-treatment tissue levels of choline compounds have potential to predict response to docetaxel treatment.

Left atrial remodeling, early repolarization pattern, and inflammatory cytokines in professional soccer players

OBJECTIVES: Although regular physical exercise clearly reduces cardiovascular morbidity risk, long-term endurance sports practice has been recognized as a risk factor for atrial fibrillation (AF). However, the mechanisms how endurance sports can lead to AF are not yet clear. The aim of our present study was to investigate the influence of long-term endurance training on vagal tone, atrial size, and inflammatory profile in professional elite soccer players. METHODS: A total of 25 professional major league soccer players (mean age 24+/-4 years) and 20 sedentary controls (mean age 26+/-3 years) were included in the study and consecutively examined. All subjects underwent a sports cardiology check-up with physical examination, electrocardiography, echocardiography, exercise testing on a bicycle ergometer, and laboratory analysis [standard laboratory and cytokine profile: interleukin (IL)-6, tumor necrosis factor (TNF)-alpha, IL-8, IL-10]. RESULTS: Athletes were divided into two groups according to presence or absence of an early repolarization (ER) pattern, defined as a ST-segment elevation at the J-point (STE) >/=0.1mm in 2 leads. Athletes with an ER pattern showed significantly lower heart rate and an increased E/e' ratio compared to athletes without an ER pattern. STE significantly correlated with E/e' ratio as well as with left atrial (LA) volume. The pro-inflammatory cytokines IL-6, IL-8, TNF-alpha as well as the anti-inflammatory cytokine IL-10 were significantly elevated in all soccer players. However, athletes with an ER pattern had significantly higher IL-6 plasma levels than athletes without ER pattern. Furthermore, athletes with "high" level IL-6 had significantly larger LA volumes than players with "low" level IL-6. CONCLUSIONS: Athletes with an ER pattern had significantly higher E/e' ratios, reflecting higher atrial filling pressures, higher LA volume, and higher IL-6 plasma levels. All these factors may contribute to atrial remodeling over time and thus increase the risk of AF in long-term endurance sports.

Sex differences in heart rate variability: a longitudinal study in international elite cross-country skiers

PURPOSE: Exercise-related sudden cardiac deaths (SCD) occur with a striking male predominance. A higher sympathetic tone in men has been suggested as risk factor for SCD. Elite athletes have the highest risk for exercise-related SCD. We aimed to analyze the autonomic nervous system of elite cross-country skiers from Norway, Russia and Switzerland in supine position and after orthostatic challenge in various training periods (TP). METHOD: Measurements of heart rate variability (HRV) were performed on a weekly basis over 1 year using an orthostatic challenge test with controlled breathing. Main outcome parameters were the high-frequency power in supine position (HFsupine) as marker of cardiac parasympathetic activity and the low-frequency/high-frequency power ratio after orthostatic challenge (LF/HFstand) as marker of cardiac sympathetic activation. Training intensity and duration were recorded daily and expressed as training strain. The training year was divided into three TPs. An average of weekly HRV measurements was calculated for each TP. RESULT: Female (n = 19, VO2max 62.0 +/- 4.6 ml kg(-1) min(-1), age 25.8 +/- 4.3 years) and male (n = 16, VO2max 74.3 +/- 6.3 ml kg(-1) min(-1), age 24.4 +/- 4.2 years) athletes were included. Training strain was comparable between sexes (all p > 0.05) and changed between TPs (all p < 0.05) while no HRV parameters changed over time. There were no sex differences in HFsupine while the LF/HFstand was significantly higher in male athletes in all TPs. CONCLUSION: For a comparable amount of training, male athletes showed constantly higher markers of sympathetic activity after a provocation maneuver. This may explain part of the male predominance in sports-related SCD.

The Effect of Increasing Intracranial Pressure on Ocular Vestibular-Evoked Myogenic Potential Frequency Tuning.

OBJECTIVE Ocular vestibular-evoked myogenic potentials (oVEMPs) represent extraocular muscle activity in response to vestibular stimulation. The authors sought to investigate whether posture-induced increase of the intracranial pressure (ICP) modulated oVEMP frequency tuning, that is, the amplitude ratio between 500-Hz and 1000-Hz stimuli. DESIGN Ten healthy subjects were enrolled in this study. The subjects were positioned in the horizontal plane (0 degree) and in a 30-degree head-downwards position to elevate the ICP. In both positions, oVEMPs were recorded using 500-Hz and 1000-Hz air-conducted tone bursts. RESULTS When tilting the subject from the horizontal plane to the 30-degree head-down position, oVEMP amplitudes in response to 500-Hz tone bursts distinctly decreased (3.40 μV versus 2.06 μV; p < 0.001), whereas amplitudes to 1000 Hz were only slightly diminished (2.74 μV versus 2.48 μV; p = 0.251). Correspondingly, the 500/1000-Hz amplitude ratio significantly decreased when tilting the subjects from 0- to 30-degree inclination (1.59 versus 1.05; p = 0.029). Latencies were not modulated by head-down position. CONCLUSIONS Increasing ICP systematically alters oVEMPs in terms of absolute amplitudes and frequency tuning characteristics. oVEMPs are therefore in principle suited for noninvasive ICP monitoring.