Assessment and characterization of the genetic diversity of viruses infecting cultivated yams (Dioscorea spp.) in Haïti

Several viral species are known to infect yams (Dioscorea spp.) and to generate important yield losses on this vegetative propagated crop. Within the framework of the DEVAG project (Caribbean network for the development of agroecological horticultural systems) funded by the INTERREG IV Caribbean program, the inventory, the characterization and the prevalence of viruses infecting yams in Haïti have been undertaken to assess their impact on culture and to suggest appropriate control methods. Approximately four hundred samples belonging to five yam species cultivated in Haïti (D. alata, D. bulbifera, D. cayenensis, D. rotundata, D. trifida) were collected in 2009 in farmers' fields in the five growing regions of yam. Virus detection was performed using broad spectrum PCR and RT-PCR tests targeting badnaviruses, CMV (genus Cucumovirus), potexviruses and potyviruses, after direct binding of viral particles on PCR tubes. Ninety four samples were infected by at least one of those viruses. The Badnavirus genus represents the most prevalent viral type. Hence, badnavirus RnaseH gene fragment (528 bp) was detected and amplified from most of the D. bulbifera samples (15/18) and D. trifida samples (6/6), and in half of the D. alata samples (61/132). Genetic diversity of these sequences is high (50- 97%) and these sequences belong to six out of thirteen groups of yam badnaviruses identified by Kenyon et al. (2008). Analysis of the potyvirus sequences (CP - 282 bp) obtained from ten samples revealed the existence of YMMV on D. alata (7/132) and D. trifida (1/6) samples. Similarly, two strains of a new potyvirus were found in D. trifida samples (2/6) with a nucleotide identity of 74-79% with two viral species, ALiMV and PTV. Furthermore, three sequences (245 bp) related to the RdRp gene of potexviruses, with 71-78% of nucleotide identity with PAMV and PepMV were found in two D. bulbifera and D. rotundata plants. This is the first inventory of yam viruses in Haïti which highlights a high viral prevalence rate with large amount of diversity within each virus species tested. Excepted for badnaviruses for which impact on yam production is misunderstood, the pressure of RNA viruses appears to be very low for the most common varieties, but strong for the rarer cultivars suggesting that a dramatic varietal genetic erosion is underway. (Texte intégral

Pharyngeal electrical stimulation for treatment of dysphagia in subacute stroke

Background and Purpose: Dysphagia is common after stroke, associated with increased death and dependency, and treatment options are limited. Pharyngeal electric stimulation (PES) is a novel treatment for poststroke dysphagia that has shown promise in 3 pilot randomized controlled trials. Methods: We randomly assigned 162 patients with a recent ischemic or hemorrhagic stroke and dysphagia, defined as a penetration aspiration score (PAS) of ≥3 on video fluoroscopy, to PES or sham treatment given on 3 consecutive days. The primary outcome was swallowing safety, assessed using the PAS, at 2 weeks. Secondary outcomes included dysphagia severity, function, quality of life, and serious adverse events at 6 and 12 weeks. Results: In randomized patients, the mean age was 74 years, male 58%, ischemic stroke 89%, and PAS 4.8. The mean treatment current was 14.8 (7.9) mA and duration 9.9 (1.2) minutes per session. On the basis of previous data, 45 patients (58.4%) randomized to PES seemed to receive suboptimal stimulation. The PAS at 2 weeks, adjusted for baseline, did not differ between the randomized groups: PES 3.7 (2.0) versus sham 3.6 (1.9), P=0.60. Similarly, the secondary outcomes did not differ, including clinical swallowing and functional outcome. No serious adverse device-related events occurred. Conclusions: In patients with subacute stroke and dysphagia, PES was safe but did not improve dysphagia. Undertreatment of patients receiving PES may have contributed to the neutral result. Clinical Trial Registration: URL: http://www.controlled-trials.com. Unique identifier: ISRCTN25681641

Results from the tranexamic acid for primary intracerebral haemorrhage-2 (TICH-2) trial

Background: Haematoma expansion leads to worse outcome in intracerebral haemorrhage (ICH). Tranexamic acid (TXA) is a promising haemostatic agent to prevent haematoma expansion and improve outcome after ICH. Methods: TICH-2 is a multicentre prospective double blind randomised controlled trial, which recruited patients presenting within 8 hours of primary ICH to receive intravenous TXA or placebo. Primary outcome is modified Rankin Scale at day 90 and will be analysed using ordinal logistic regression, adjusted for minimisation criteria. Secondary outcomes will be analysed using adjusted binary logistic regression and multiple linear regression; these include haematoma expansion at 24 hours, day 7 National Institute of Health Stroke Scale (NIHSS), day 90 Barthel Index, quality of life, cognition and mood. Results: A total of 2325 patients were recruited between 14th March 2013 and 30th September 2017, from 12 countries: United Kingdom (n= 1910), Italy, Georgia, Switzerland, Malaysia, Hungary, Poland, Ireland, Turkey, Sweden, Denmark and Spain. Randomisation characteristics included: age 68.9 (13.8) years; male 1301 (56.0%); time from onset to randomisation 3.6 hours [2.6, 5.0]; NIHSS 13 (7.5); Glasgow coma scale 13.4 (2.1); systolic blood pressure 172.6 (27.2) mmHg; intraventricular haemorrhage 745 (32.0%) and prior antiplatelet use 610 (26.2%). Conclusion: TICH-2 is the largest trial of TXA in spontaneous ICH and recruited over its original target of 2000 patients. The results will be available in May 2018 and will inform whether TXA should be recommended for the treatment of acute spontaneous ICH

Consent procedures and relationship with outcome in the Rapid Intervention with Glyceryl trinitrate in Hypertensive stroke Trial-2 (RIGHT-2)

Background: Obtaining consent in emergency situations is challenging. Proxy consent allows patients to be recruited when they lack capacity, a common scenario in stroke patients. The rapid intervention with glyceryl trinitrate in hypertensive stroke trial-2 (RIGHT-2) recruits patients in the pre-hospital setting within 4 hours of stroke onset. Methods: In RIGHT-2, informed or proxy consent is taken in the ambulance. A brief assessment of capacity is performed by the paramedic. Patients with capacity provide consent and in patients without capacity, proxy consent is obtained from a relative, carer or friend, or by the paramedic, witnessed by a crew member. Results: Of 879 participants enrolled into RIGHT-2 as of 15th December 2017, 468 (53.2%) participants gave their own consent; proxy consent was given by a relative/carer/friend for 325 (37%) and by a paramedic for 85 (9.7%). Participants who consented themselves were younger, had less dependency and had less severe strokes than those with proxy consent. Participants who gave their own consent had a lower rate of intracerebral haemorrhage (9% vs 16%) and a higher rate of non-stroke (20% vs 13%) as their final diagnosis than those who gave proxy consent. Consenting patients had better scores for dependency, cognition, disability and quality of life at day 90 than those recruited via proxy consent. Conclusion: Proxy consent can ensure participants are enrolled rapidly into emergency clinical trials where they may otherwise be excluded due to lack of capacity. These patients have more severe strokes and therefore poorer clinical outcomes

Superheated Microdrops as Cold Dark Matter Detectors

It is shown that under realistic background considerations, an improvement in Cold Dark Matter sensitivity of several orders of magnitude is expected from a detector based on superheated liquid droplets. Such devices are totally insensitive to minimum ionizing radiation while responsive to nuclear recoils of energies ~ few keV. They operate on the same principle as the bubble chamber, but offer unattended, continuous, and safe operation at room temperature and atmospheric pressure.Comment: 15 pgs, 4 figures include

Baseline characteristics of the 3,096 patients recruited into the 'Triple Antiplatelets for Reducing Dependency after Ischaemic Stroke' (TARDIS) trial

Background: The risk of recurrence following ischaemic stroke (IS) or transient ischaemic attack (TIA) is highest immediately after the event. Antiplatelet agents are effective in reducing the risk of recurrence and two agents are superior to one in the early phase after ictus. Design: The Triple Antiplatelets for Reducing Dependency after Ischaemic Stroke (TARDIS) trial was an international multicentre prospective randomised open-label blinded-endpoint trial that assessed the safety and efficacy of short-term intensive antiplatelet therapy with three agents (combined aspirin, clopidogrel and dipyridamole) as compared with guideline treatment in acute IS or TIA. The primary outcome was stroke recurrence and its severity, measured using the modified Rankin Scale at 90 days. Secondary outcomes included recurrent vascular events, functional measures (cognition, disability, mood, quality of life) and safety (bleeding, death, serious adverse events). Data are number (%) or mean (standard deviation, SD). Results: Recruitment ran from April 2009 to March 2016. 3,096 patients were recruited from 106 sites in 4 countries (Denmark 1.6%, Georgia 2.7%, New Zealand 0.2%, UK 95.4%). Randomisation characteristics included: age 69.0 (10.1) years; male 1945 (62.8%); time onset to randomisation 29.4 (11.9) hours; stroke severity (National Institutes for Health Stroke Scale) 2.8 (3.6); blood pressure 143.5 (18.2)/79.5 (11.4) mmHg; IS 2143 (69.2%), TIA 953 (30.8%). Conclusion: TARDIS was a large trial of intensive/triple antiplatelet therapy in acute IS and TIA, and included participants from four predominantly Caucasian countries who were representative of patients in many western stroke services

Antiplatelet therapy with aspirin, clopidogrel, and dipyridamole versus clopidogrel alone or aspirin and dipyridamole in patients with acute cerebral ischaemia (TARDIS): a randomised, open-label, phase 3 superiority trial

Background: Intensive antiplatelet therapy with three agents might be more effective than guideline treatment for preventing recurrent events in patients with acute cerebral ischaemia. We aimed to compare the safety and efficacy of intensive antiplatelet therapy (combined aspirin, clopidogrel, and dipyridamole) with that of guideline-based antiplatelet therapy. Methods: We did an international, prospective, randomised, open-label, blinded-endpoint trial in adult participants with ischaemic stroke or transient ischaemic attack (TIA) within 48 h of onset. Participants were assigned in a 1:1 ratio using computer randomisation to receive loading doses and then 30 days of intensive antiplatelet therapy (combined aspirin 75 mg, clopidogrel 75 mg, and dipyridamole 200 mg twice daily) or guideline-based therapy (comprising either clopidogrel alone or combined aspirin and dipyridamole). Randomisation was stratified by country and index event, and minimised with prognostic baseline factors, medication use, time to randomisation, stroke-related factors, and thrombolysis. The ordinal primary outcome was the combined incidence and severity of any recurrent stroke (ischaemic or haemorrhagic; assessed using the modified Rankin Scale) or TIA within 90 days, as assessed by central telephone follow-up with masking to treatment assignment, and analysed by intention to treat. This trial is registered with the ISRCTN registry, number ISRCTN47823388. Findings: 3096 participants (1556 in the intensive antiplatelet therapy group, 1540 in the guideline antiplatelet therapy group) were recruited from 106 hospitals in four countries between April 7, 2009, and March 18, 2016. The trial was stopped early on the recommendation of the data monitoring committee. The incidence and severity of recurrent stroke or TIA did not differ between intensive and guideline therapy (93 [6%] participants vs 105 [7%]; adjusted common odds ratio [cOR] 0·90, 95% CI 0·67–1·20, p=0·47). By contrast, intensive antiplatelet therapy was associated with more, and more severe, bleeding (adjusted cOR 2·54, 95% CI 2·05–3·16, p<0·0001). Interpretation: Among patients with recent cerebral ischaemia, intensive antiplatelet therapy did not reduce the incidence and severity of recurrent stroke or TIA, but did significantly increase the risk of major bleeding. Triple antiplatelet therapy should not be used in routine clinical practice

Passage and concentration-dependent effects of Indomethacin on tendon derived cells

<p>Abstract</p> <p>Background</p> <p>Non-steroidal anti-inflammatory drugs (NSAID) are commonly used in the treatment of tendinopathies such as tendonitis and tendinosis. Despite this, little is known of their direct actions on tendon-derived cells. As NSAIDs have been shown to delay healing in a number of mesenchymal tissues we have investigated the direct effects of indomethacin on the proliferation of tendon-derived cells.</p> <p>Results and Discussion</p> <p>The results obtained were dependent on both the type of cells used and the method of measurement. When measured using the Alamar blue assay, a common method for the measurement of cell proliferation and viability, no effect of indomethacin was seen regardless of cell source. It is likely that this lack of effect was due to a paucity of mitochondrial enzymes in tendon cells.</p> <p>However, when cell number was assessed using the methylene blue assay, which is a simple nuclear staining technique, an Indomethacin-induced inhibition of proliferation was seen in primary cells but not in secondary subcultures.</p> <p>Conclusion</p> <p>These results suggest that firstly, care must be taken when deciding on methodology used to investigate tendon-derived cells as these cells have a quite different metabolism to other mesenchymal derive cells. Secondly, Indomethacin can inhibit the proliferation of primary tendon derived cells and that secondary subculture selects for a population of cells that is unresponsive to this drug.</p

The Transient Receptor Potential Ion Channel TRPV6 Is Expressed at Low Levels in Osteoblasts and Has Little Role in Osteoblast Calcium Uptake

Background: TRPV6 ion channels are key mediators of regulated transepithelial absorption of Ca2+ within the small intestine. Trpv6-/- mice were reported to have lower bone density than wild-type littermates and significant disturbances in calcium homeostasis that suggested a role for TRPV6 in osteoblasts during bone formation and mineralization. TRPV6 and molecules related to transepithelial Ca2+ transport have been reported to be expressed at high levels in human and mouse osteoblasts. Results: Transmembrane ion currents in whole cell patch clamped SaOS-2 osteoblasts did not show sensitivity to ruthenium red, an inhibitor of TRPV5/6 ion channels, and 45Ca uptake was not significantly affected by ruthenium red in either SaOS-2 (P = 0.77) or TE-85 (P = 0.69) osteoblastic cells. In contrast, ion currents and 45Ca uptake were both significantly affected in a human bronchial epithelial cell line known to express TRPV6. TRPV6 was expressed at lower levels in osteoblastic cells than has been reported in some literature. In SaOS-2 TRPV6 mRNA was below the assay detection limit; in TE-85 TRPV6 mRNA was detected at 6.90±1.9 × 10−5 relative to B2M. In contrast, TRPV6 was detected at 7.7±3.0 × 10−2 and 2.38±0.28 × 10−4 the level of B2M in human carcinoma-derived cell lines LNCaP and CaCO-2 respectively. In murine primary calvarial osteoblasts TRPV6 was detected at 3.80±0.24 × 10−5 relative to GAPDH, in contrast with 4.3±1.5 × 10−2 relative to GAPDH in murine duodenum. By immunohistochemistry, TRPV6 was expressed mainly in myleocytic cells of the murine bone marrow and was observed only at low levels in murine osteoblasts, osteocytes or growth plate cartilage. Conclusions: TRPV6 is expressed only at low levels in osteoblasts and plays little functional role in osteoblastic calcium uptake

Prehospital transdermal glyceryl trinitrate in patients with ultra-acute presumed stroke (RIGHT-2): an ambulance-based, randomised, sham-controlled, blinded, phase 3 trial

BACKGROUND:High blood pressure is common in acute stroke and is a predictor of poor outcome; however, large trials of lowering blood pressure have given variable results, and the management of high blood pressure in ultra-acute stroke remains unclear. We investigated whether transdermal glyceryl trinitrate (GTN; also known as nitroglycerin), a nitric oxide donor, might improve outcome when administered very early after stroke onset. METHODS:We did a multicentre, paramedic-delivered, ambulance-based, prospective, randomised, sham-controlled, blinded-endpoint, phase 3 trial in adults with presumed stroke within 4 h of onset, face-arm-speech-time score of 2 or 3, and systolic blood pressure 120 mm Hg or higher. Participants were randomly assigned (1:1) to receive transdermal GTN (5 mg once daily for 4 days; the GTN group) or a similar sham dressing (the sham group) in UK-based ambulances by paramedics, with treatment continued in hospital. Paramedics were unmasked to treatment, whereas participants were masked. The primary outcome was the 7-level modified Rankin Scale (mRS; a measure of functional outcome) at 90 days, assessed by central telephone follow-up with masking to treatment. Analysis was hierarchical, first in participants with a confirmed stroke or transient ischaemic attack (cohort 1), and then in all participants who were randomly assigned (intention to treat, cohort 2) according to the statistical analysis plan. This trial is registered with ISRCTN, number ISRCTN26986053. FINDINGS:Between Oct 22, 2015, and May 23, 2018, 516 paramedics from eight UK ambulance services recruited 1149 participants (n=568 in the GTN group, n=581 in the sham group). The median time to randomisation was 71 min (IQR 45-116). 597 (52%) patients had ischaemic stroke, 145 (13%) had intracerebral haemorrhage, 109 (9%) had transient ischaemic attack, and 297 (26%) had a non-stroke mimic at the final diagnosis of the index event. In the GTN group, participants' systolic blood pressure was lowered by 5·8 mm Hg compared with the sham group (p<0·0001), and diastolic blood pressure was lowered by 2·6 mm Hg (p=0·0026) at hospital admission. We found no difference in mRS between the groups in participants with a final diagnosis of stroke or transient ischaemic stroke (cohort 1): 3 (IQR 2-5; n=420) in the GTN group versus 3 (2-5; n=408) in the sham group, adjusted common odds ratio for poor outcome 1·25 (95% CI 0·97-1·60; p=0·083); we also found no difference in mRS between all patients (cohort 2: 3 [2-5]; n=544, in the GTN group vs 3 [2-5]; n=558, in the sham group; 1·04 [0·84-1·29]; p=0·69). We found no difference in secondary outcomes, death (treatment-related deaths: 36 in the GTN group vs 23 in the sham group [p=0·091]), or serious adverse events (188 in the GTN group vs 170 in the sham group [p=0·16]) between treatment groups. INTERPRETATION:Prehospital treatment with transdermal GTN does not seem to improve functional outcome in patients with presumed stroke. It is feasible for UK paramedics to obtain consent and treat patients with stroke in the ultra-acute prehospital setting. FUNDING:British Heart Foundation