Use of an image analyser to study the imbibition process of Melia dubia seeds

An image analyser system was used to study the process of imbibition in Melia dubia seeds, and in comparison with the conventional method of measuring seed weight by an electronic balance. Melia dudia drupes were divided into three groups and treated accordingly: drupes with intact pericarp, drupes with punctured pericarp and naked seeds without pericarp. Using seed weight and perimeter as parameters, the imbibition process in the seed samples were described by a series of imbibition curves illustrative of the triphasic pattern of water uptake during germination. The image analyser captured small variation in seed parameters between the groups. The sensitivity and feasibility of the advanced method of using an image analyser to investigate individual seeds within a population imply that the image analyser has high potential in advancing seed biology studies.

THU0318 PATTERNS OF CLINICAL PRESENTATION IN TAKAYASU’S ARTERITIS

Background:Takayasu’s arteritis (TAK) is a clinically heterogenous disease. Patterns of clinical presentation in TAK at diagnosis have not been well described, and a “triphasic pattern” of constitutional symptoms evolving into vascular inflammation and fibrosis has been reported but never systematically evaluated.Objectives:To describe patterns of clinical presentation in TAK at diagnosis and evaluate the presence of an antecedent triphasic disease pattern in patients with TAK who presented with a major ischemic event at diagnosis.Methods:Patients with TAK were prospectively recruited from the National Institutes of Health (NIH) and the Vasculitis Clinical Research Consortium (VCRC). All patients fulfilled the 1990 American College of Rheumatology (ACR) Classification Criteria for TAK. Based on clinical presentation at diagnosis, patients were divided into five groups from the different stages of the triphasic pattern of disease as follows: 1) constitutional symptoms (phase I), 2) carotidynia (phase II), 3) other vascular-associated symptoms (phase II), 4) major ischemic event (phase III) defined as CVA or TIA, retinal ischemia, MI, renovascular hypertension, or mesenteric ischemia, or 5) asymptomatic. Phase II was divided into two separate groups because patients with carotidynia reportedly have a higher rate of relapsing disease.Associated clinical characteristics were evaluated in each group and differences among groups were assessed by chi square test and Kruskal-Wallis test, as appropriate. Preceding symptoms were also assessed to determine the presence of a triphasic disease pattern.Results:A total of 275 patients with TAK were included (VCRC=208; NIH=67). Similar heterogeneity of clinical presentation was identified in each cohort: constitutional symptoms (8%), carotidynia (13-15%), other vascular symptoms (43-47%), major ischemic event (28-30%), and asymptomatic (2-6%). Frequency of male gender was more common in patients who presented with constitutional symptoms or were asymptomatic at diagnosis (p<0.01). Patients who presented with constitutional symptoms and major ischemic events were youngest at diagnosis. Patients in the asymptomatic group were oldest at diagnosis and often were not treated (p<0.01). Involvement of the abdominal vasculature was associated with major ischemic events and asymptomatic presentations. Major ischemic events after diagnosis were infrequent in the groups who did not present with a major ischemic event, occurring in 10-20% cases. Relapse (p<0.01) and recurrent pharyngitis preceding diagnosis (p<0.01) was most frequent in patients who presented with carotidynia.A total of 79 patients [VCRC=59 patients, NIH=20 patients] presented with a major ischemic event. The majority of these patients (53%) reported symptoms of active disease prior to the major ischemic event. Few patients (19%) who presented with a major ischemic event reported a triphasic pattern of disease.Conclusion:There is heterogeneity in clinical presentation at the time of diagnosis in TAK and this heterogeneity can be used to group patients according to pattern of disease presentation. Patients do not necessarily progress sequentially through phases of disease, but the majority of patients presenting with a major ischemic event report some preceding symptoms. Data from this study demonstrate distinct subgroups within TAK and supports the concept that TAK is possibly a heterogenous collection of multiple diseases.References:N/ADisclosure of Interests:None declared

P.008 Triphasic waves in powassan encephalitis: a case report

Background: Powassan virus is a tick borne virus which can lead to encephalitis. Methods: 63 year old woman with history of migraine presented with 2 days of fever, headache, language difficulty and right sided facial droop. Her examination revealed right upper motor neuron type facial weakness and expressive aphasia. She rapidly deteriorated within 24 hours becoming non verbal and ultimately comatose. Results: MRI brain revealed T2 hyperintensities in bilateral caudate and putamen. Subsequent MRI brain showed progression of the caudate and basal ganglia changes and new T2 hyperintensities in bilateral thalami and midbrain with no abnormal enhancement. CSF revealed lymphocytic pleocytosis with normal protein and glucose. Viral Encephalitis was suspected and she was continued on Acyclovir until Varicella zoster and Herpes simplex virus serology in CSF returned negative. Prolonged video EEG showed near continuous generalized triphasic pattern without any evolution or seizure pattern. There was no improvement in clinical status or EEG with antiepileptic treatment. Paraneoplastic panel , serum HIV, Lyme and 14-3-3 protein were negative. Extensive viral serologies were sent and ultimately Powassan serology came back positive. Conclusions: This case highlights powassan virus as a cause of encephalitis and occurrence of triphasic waves in non metabolic causes of encephalopathy such as infectious encephalitis.

On the timing and duration of foraging in Onchidella celtica

Time-lapse photography was used to study the timing and duration of foraging activity of a population of the pulmonate gastropod Onchidella celtica on an exposed rocky shore in Cornwall, UK. The pulmonates spent most of their time in their home crevice, emerging onto open rock only during some ebb tides to forage for food and find a mate. Total duration and speed of foraging was highly variable and did not generally conform to a triphasic pattern. The number foraging was also highly variable and was not correlated significantly with the spring/neap tide cycle or weather (air temperature above 12°C, air pressure, solar radiation, precipitation, relative humidity and wind speed). There was a significant negative correlation between foraging and surf height. Although the pulmonates foraged during all hours of the day/night cycle, foraging activity tended to be highest during the afternoon and evening.

Biometric description of fruits and seeds, germination and imbibition pattern of desert rose [Adenium obesum (Forssk.), Roem. & Schult.]

This study has aimed to carry out the description of fruits and seeds and germination process of desert rose, from two years of observations. The fruits and seeds were characterized based on length, diameter and number of seeds per fruit. The seeds internal structure and germinating process were also described. Germination test was performed at 25 and 30 °C temperatures, determining the germination percentage and germination speed index. Seeds harvested in 2013 were stored for 12 months and submitted to a new germination test. Parallel to these tests, the seeds imbibition curve was determined in substrates over and between sheets of paper at 15, 20, 25 and 30 °C temperatures. The fruits and seeds had similar lengths and diameters in both years of observations. The seeds can be stored for up to 12 months without loss in viability and temperatures of 25 and 30 °C are suitable for performing the germination test of this species. The water absorption curve of desert rose seeds follows a triphasic pattern of soaking.

Physiological, physical, and morpho-anatomical changes in Libidibia ferrea ((Mart. ex Tul.) L.P. Queiroz) seeds after overcoming dormancy

Seed dormancy is a phenomenon that affects the distribution of plant species in time. However, it may slow germination and consequently hinder seedling production in nurseries. Many seeds of forest species of the Fabaceae family, such as Libidibia ferrea (Brazilian ironwood), have physical dormancy caused by impermeability of the seed coat to water. Therefore, the aim of this study was to evaluate the physiological, physical, and morpho-anatomical characteristics of L. ferrea seeds before and after application of different treatments for overcoming dormancy. We evaluated the imbibition curves, germination percentage, germination speed index (GSI), the force required to puncture the micropylar region, and morpho-anatomical changes through images obtained from a scanning electron microscope (SEM) before and after application of treatments for overcoming dormancy. L. ferrea seeds immersed in sulfuric acid show a triphasic pattern of imbibition. The required force to puncture the micropylar region of L. ferrea seeds is less for both the treatment with boiling water and for treatments with sulfuric acid. In addition, the required force to puncture the micropylar region decreases during imbibition of the seeds after application of sulfuric acid. The time of application of sulfuric acid influences the thickness of the material removed from the macrosclereid layer of the seed coat.

Startle reveals independent preparation and initiation of triphasic EMG burst components in targeted ballistic movements

Muscles involved in rapid, targeted movements about a single joint often display a triphasic [agonist (AG1)-antagonist (ANT)-agonist (AG2)] electromyographic (EMG) pattern. Early work using movement perturbations suggested that for short movements, the entire EMG pattern was prepared and initiated in advance (Wadman WJ, Dernier van der Gon JJ, Geuze RH, Mol CR. J Hum Mov Stud 5: 3–17, 1979), whereas more recent transcranial magnetic stimulation evidence indicates that the ANT may be programmed separately (MacKinnon CD, Rothwell JC. J Physiol 528: 633–645, 2000) with execution of the bursts occurring serially (Irlbacher K, Voss M, Meyer BU, Rothwell JC. J Physiol 574: 917–928, 2006). The purpose of the current study was to investigate the generation of triphasic EMG bursts for movements of different amplitudes. In experiment 1, participants performed rapid elbow extension movements to 20° and 60° targets, and on some trials, a startling acoustic stimulus (SAS), which is thought to trigger prepared motor commands at short latency, was delivered at the onset of AG1. For short movements, this perturbation elicited ANT and AG2 early, suggesting the agonist and antagonist bursts may have been programmed independently. In contrast, the same manipulation did not disrupt EMG timing parameters for the long movements, raising the possibility that ANT and AG2 were not fully programmed in advance of movement onset. In experiment 2, an SAS was delivered later in the movement, which produced early onset of both ANT and AG2. We propose that the triphasic pattern is executed serially but believe the trigger signal for initiating the ANT burst occurs not in relation to the AG1 burst, but rather in close temporal proximity to the expected onset of ANT.

Soaking curve and effect of temperature on the germination of daisy seeds

The soaking curve and the effect of temperature on the germination of daisy seeds (Chrysanthemum leucanthemum) were characterized in this study. To determine the soaking curve, four samples of 0.5 g of seeds were soaked in germitest paper moistened with distilled water and maintained in germinator at 25ºC. The seeds were weighed in periods of 0, 3, 6, 9, 12, 24, 36, 48, 60, 72, 84 and 96 hours using a precision digital balance of 0.0001 g. A triphasic pattern germination curve was adjusted, allowing the determination of the beginning and duration of the phase II of the germination process. The germination test was carried out with four replications of 50 seeds disposed in "Gerbox" boxes and placed in germinators at the temperatures of 20, 25, 30 or 20-30ºC. A completely randomized experimental design was used with four replications of 50 seeds. The data were submitted to the analysis of variance and the averages were compared by the Tukey test, at 5% of probability. For analysis of accumulated seed germination, regressions were adjusted based on period of experiment. The seeds presented a triphasic pattern of germination and the phases I and II lasted 12 and 48 hours, respectively. The best temperature for the germination of the seeds is 25ºC. The temperature of 30ºC promoted the thermoinhibition of germination and increased the dead and dormant seeds and abnormal seedlings.