Vacancy-mediated mechanism of nitrogen substitution in carbon nanotubes

Nitrogen substitution reaction in a graphene sheet and carbon nanotubes of different diameter are investigated using the generalized tight-binding molecular dynamics method. The formation of a vacancy in curved graphene sheet or a carbon nanotube is found to cause a curvature dependent local reconstruction of the surface. Our simulations and analysis show that vacancy mediated N substitution (rather than N chemisorption) is favored on the surface of nanotubes with diameter larger than 8 nm. This predicted value of the critical minimum diameter for N incorporation is confirmed by experimental results presented on nitrogen-doped multiwalled nanotubes with [approximate]5 at. % nitrogen prepared by the thermal chemical vapor deposition process

Kernohan-Woltman notch phenomenon and intention tremors in case of chronic subdural hematoma

Movement disorders are atypical and rare presentation of chronic subdural hematomas. We report a case of 60 year man who presented with intention tremors and altered sensorium. The patient had Kernohan-Woltman notch phenomenon on clinical examination. CT scan brain showed a large left fronto-temporo-parietal chronic subdural hematoma with significant mass effect and midline shift. His symptoms relieved completely after surgical evacuation of the hematoma

Newborn friendly thermometry – Comparative study of body temperature with an infrared versus digital thermometer

Background: Accurate measurement of body temperature is of great importance in day to day neonatology practice. One touch infraredthermometry is safe, accurate, and easy to use. Objective: We aimed at comparing infrared forehead thermometer with an axillary digitalthermometer to assess the accuracy. Methods: Axillary and forehead temperatures were measured simultaneously in normal newbornbabies using digital and infrared thermometers respectively at a tertiary level teaching hospital in northern Kerala, India and the meantemperature measured by these two methods were compared. Those babies with fever or admitted at Neonatal Intensive Care Unit werenot included in the study. Results: Totally, 193 newborns were included in the study with the mean birth weight of 2600±400 g. Therewas no significant difference in temperature measured by digital and infrared thermometers (97.74±0.91°F vs. 97.81±0.89°F, p=0.44).There was a significant positive correlation between axillary and forehead temperature (r=0.94) and mean difference between two readingswas 0.07±0.25°F (p=0.11). Conclusion: Infrared forehead thermometry is as reliable and accurate as axillary digital thermometry. Thus,infrared forehead thermometry can be used in clinical practice, especially in neonatal and postnatal wards where ease of use and speed ofobtaining the temperature readings are important

Randomized controlled trial of antenatal magnesium sulfate for short-term neuroprotection in premature neonates

Objective: To test the hypothesis that antenatal magnesium sulfate (MgSO4) has a short term neuroprotective role in the early neonatal period, when given to women considered at risk for preterm delivery in a developing country. Study Design: Randomized, placebo-controlled, open label, trial. Participants: A total of 126 mothers who delivered at or below 34 weeks gestation were randomized to receive either antenatal MgSO4 (cases) or normal saline as placebo (controls). A total of 108 babies born were observed for the primary and secondary outcomes. Primary Outcome: The composite of the incidence of death and intraventricular hemorrhage (IVH) by cranial ultrasonography in surviving preterm infants. Results: There were 6 deaths in cases and 11 deaths in controls (relative risk [RR]: 0.54; 95% confidence interval [CI]: 0.2173-1.369; p=0.18). A statistically significant reduction in the number of IVH was observed in cases (n=1) compared to controls (n=9) (RR: 0.11; 95% CI: 0.0145-0.897; p=0.016) with a number needed to treat of 7. Conclusion: Antenatal MgSO4 resulted in a significant reduction in the risk of IVH in preterm infants born at or below 34 weeks of gestation

Takayasu's disease presenting as convulsive syncope which had been misinterpreted as epilepsy: a case report

<p>Abstract</p> <p>Introduction</p> <p>Takayasu's arteritis is a chronic vasculitis mainly involving the aorta and its main branches. The disease has protean clinical manifestation ranging from asymptomatic to catastrophic illness.</p> <p>Case presentation</p> <p>A 19-year-old woman of Asian origin was referred to our neurology out-patient department for the management of refractory seizures. She reported several episodes of a loss of consciousness with tonic posturing when she assumed an upright position, which was accompanied by constitutional symptoms. A clinical examination showed orthostatic hypotension and an investigation confirmed the diagnosis of Takayasu's disease with presentation as convulsive syncope.</p> <p>Conclusion</p> <p>Our case highlights the importance of a thorough clinical history and physical examination in order to distinguish events mimicking epileptic seizure. We also describe an unusual presentation of Takayasu's disease with convulsive syncope and systemic constitutional symptoms.</p

Effects of antiplatelet therapy on stroke risk by brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases: subgroup analyses of the RESTART randomised, open-label trial

Background Findings from the RESTART trial suggest that starting antiplatelet therapy might reduce the risk of recurrent symptomatic intracerebral haemorrhage compared with avoiding antiplatelet therapy. Brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases (such as cerebral microbleeds) are associated with greater risks of recurrent intracerebral haemorrhage. We did subgroup analyses of the RESTART trial to explore whether these brain imaging features modify the effects of antiplatelet therapy

The Sirtuin Family Members SIRT1, SIRT3 and SIRT6: Their Role In Vascular Biology and Atherogenesis

The sirtuins, silent mating-type information regulation 2 (SIRTs), are a family of nicotinamide adenine dinucleotide (NAD+)-dependent histone deacetylases with important roles in regulating energy metabolism and senescence. Activation of SIRTs appears to have beneficial effects on lipid metabolism and antioxidants, prompting investigation of the roles of these proteins in atherogenesis. Although clinical data are currently limited, the availability and safety of SIRT activators such as metformin and resveratrol provide an excellent opportunity to conduct research to better understand the role of SIRTs in human atherosclerosis. Encouraging observations from preclinical studies necessitate rigorous large, prospective, randomized clinical trials to determine the roles of SIRT activators on the progression of atherosclerosis and ultimately on cardiac outcomes, such as myocardial infarction and mortality

Effects of antiplatelet therapy after stroke due to intracerebral haemorrhage (RESTART): a randomised, open-label trial

Background: Antiplatelet therapy reduces the risk of major vascular events for people with occlusive vascular disease, although it might increase the risk of intracranial haemorrhage. Patients surviving the commonest subtype of intracranial haemorrhage, intracerebral haemorrhage, are at risk of both haemorrhagic and occlusive vascular events, but whether antiplatelet therapy can be used safely is unclear. We aimed to estimate the relative and absolute effects of antiplatelet therapy on recurrent intracerebral haemorrhage and whether this risk might exceed any reduction of occlusive vascular events. Methods: The REstart or STop Antithrombotics Randomised Trial (RESTART) was a prospective, randomised, open-label, blinded endpoint, parallel-group trial at 122 hospitals in the UK. We recruited adults (≥18 years) who were taking antithrombotic (antiplatelet or anticoagulant) therapy for the prevention of occlusive vascular disease when they developed intracerebral haemorrhage, discontinued antithrombotic therapy, and survived for 24 h. Computerised randomisation incorporating minimisation allocated participants (1:1) to start or avoid antiplatelet therapy. We followed participants for the primary outcome (recurrent symptomatic intracerebral haemorrhage) for up to 5 years. We analysed data from all randomised participants using Cox proportional hazards regression, adjusted for minimisation covariates. This trial is registered with ISRCTN (number ISRCTN71907627). Findings: Between May 22, 2013, and May 31, 2018, 537 participants were recruited a median of 76 days (IQR 29–146) after intracerebral haemorrhage onset: 268 were assigned to start and 269 (one withdrew) to avoid antiplatelet therapy. Participants were followed for a median of 2·0 years (IQR [1·0– 3·0]; completeness 99·3%). 12 (4%) of 268 participants allocated to antiplatelet therapy had recurrence of intracerebral haemorrhage compared with 23 (9%) of 268 participants allocated to avoid antiplatelet therapy (adjusted hazard ratio 0·51 [95% CI 0·25–1·03]; p=0·060). 18 (7%) participants allocated to antiplatelet therapy experienced major haemorrhagic events compared with 25 (9%) participants allocated to avoid antiplatelet therapy (0·71 [0·39–1·30]; p=0·27), and 39 [15%] participants allocated to antiplatelet therapy had major occlusive vascular events compared with 38 [14%] allocated to avoid antiplatelet therapy (1·02 [0·65–1·60]; p=0·92). Interpretation: These results exclude all but a very modest increase in the risk of recurrent intracerebral haemorrhage with antiplatelet therapy for patients on antithrombotic therapy for the prevention of occlusive vascular disease when they developed intracerebral haemorrhage. The risk of recurrent intracerebral haemorrhage is probably too small to exceed the established benefits of antiplatelet therapy for secondary prevention