Dengue Expansion in Africa—Not Recognized or Not Happening?

An expert conference on Dengue in Africa was held in Accra, Ghana, in February 2013 to consider key questions regarding the possible expansion of dengue in Africa. Four key action points were highlighted to advance our understanding of the epidemiology of dengue in Africa. First, dengue diagnostic tools must be made more widely available in the healthcare setting in Africa. Second, representative data need to be collected across Africa to uncover the true burden of dengue. Third, established networks should collaborate to produce these types of data. Fourth, policy needs to be informed so the necessary steps can be taken to provide dengue vector control and health services.     

Sleep and sleep disorders

Sleep is a complex neurological state, with its primary function of providing rest and restoring the body's energy levels. The importance of sleep could be seen from the fact that people spend about one-third of their lifespan in sleep. Normal human sleep is divided into non-rapid eye movement (NREM) and rapid eye movement (REM) sleep, and the alteration between NREM and REM occurs about 4-5 times during a night of normal sleep. Human NREM sleep could be classified into four stages, namely, stage I, II, III and IV, representing successively deeper stages of sleep. Sleep is an active rhythmic neural process produced by several brain areas, of which the preoptic and other basal forebrain areas play a major role in the generation of NREM sleep. Interaction of the pedenculo-pontine and lateral dorsal tegmental areas with the dorsal raphae nucleus and locus coeruleus, is important for REM sleep generation. Suprachiasmatic nucleus of the hypothalamus and the pineal gland ensure that sleep and wakefulness follow a circadian periodicity of nearly 24 hours. Alterations in the quality, quantity and pattern of sleep result in sleep disorders. Persistent and repeated interruption of sleep affects the health of an individual. Undiagnosed and untreated wake/sleep complaints cause not only misery to the sufferer, but it also has socio-economic consequences. Sleep disorders cover a wide spectrum of diseases. Though there are more than 100 identified sleep/wake disorders, most sleep complaints can be categorised into five, namely, hypersomnia, insomnia, circadian rhythm disorders, parasomnias, and sleep disorders associated with mental, neurological, and other medical disorders. Researches during the last 50 years, and the advances made in clinical sleep medicine, have lead to more effective treatments for the myriad human sleep disorders. It is not possible to assign a specific reason for many of the sleep disorders, but some aspects of sleep and wakefulness are genetically influenced. But, most commonly, sleepiness during waking hours, results from volitional or forced sleep deprivation during previous nights, due to social, economic and environmental reasons. So, public awareness about sleep disorders should be an essential part of any programme aimed at global management of sleep disorders.     

Case Report: Autochthonous Blastomycosis of the Adrenal: First Case Report from Asia

Systemic endemic mycoses, such as blastomycosis, are rare in Asia and have been reported as health risks among travelers who visit or reside in an endemic area. Adrenal involvement is rarely seen in blastomycosis and has never been reported from Asia. We report the first case of blastomycosis with bilateral involvement of the adrenals in a diabetic patient residing in the state of Arunachal Pradesh, India.     

New endemic foci of schistosomiasis infections in the Philippines

Schistosomiasis affects 28 provinces in the Philippines found along the southeastern part where there is continuous rainfall throughout the year. In 2002 and 2005 respectively, two new endemic foci were reported in the northernmost (Gonzaga, Cagayan) and central (Calatrava, Negros Occidental) parts of the country.     

Comparison of proximal isovelocity surface area method and pressure half time method for evaluation of mitral valve area in patients undergoing balloon mitral valvotomy

Background: The pressure half time (PHT) method is unreliable for measurement of mitral valve area (MVA) immediately after valvotomy. The proximal isovelocity surface area (PISA) method has been used to derive mitral valve area in patients with mitral stenosis. The aim of our study was to compare PISA method and PHT method in patients undergoing percutaneous balloon mitral valvotomy (BMV). Methods: The PISA was recorded from the apex and MVA was calculated using continuity equation by the formula 2πr² Vr/Vm, where 2πr² is the hemispheric isovelocity area, Vr is the velocity at the radial distance "r" from the orifice, and Vm is the peak velocity. A plain angle correction factor (θ)/180 was used to correct the inlet angle subtended by leaflet tunnel as a result of leaflet doming. Results: MVA calculated using PISA method (r = 0.5217, P < 0.0001, SE = 0.016) and PHT (r = 0.6652, P < 0.0001, SE = 0.017) correlated well with 2D method in patients with mitral stenosis before BMV. After BMV, MVA by PISA method correlated well with 2D planimetry (r = 0.5803, P < 0.0001, SE = 0.053) but PHT showed poor correlation (r = 0.1334, P = 0.199, SE = 0.036). The variability of measurement of MVA was most marked with PHT method in the post-BMV period. Conclusion: The PISA method correlates well with 2D planimetry in patients with mitral stenosis before and after BMV and is superior to the PHT method in the post-BMV period where the latter may be unreliable.     

Magnetic resonance imaging of temporal changes of neurotoxic lesion in the rat

Destruction of striatal neurons in the rat brain, induced by intracerebral injection of N-methyl D-aspartic acid (NMDA), has been visualized noninvasively by magnetic resonance imaging (MRI). The changes in images were monitored from 12 h to one month after the stereotaxic microinfusion of NMDA (10 μg in 0.4 μl) into the striatum, using a T₂-weighted rapid acquisition by relaxation enhancement (RARE) sequence. A localised hyperintense (bright) area was visible after 12 h at the site of the injection, and it persisted for the next three days. The size of the hyperintense area decreased thereafter and, after one week, the increased brightness was restricted to the lateral ventricle. Post-mortem histological examination, done after one month, showed a dilated lateral ventricle. The size and location of the lesioned area, identified in histological sections, corresponded to the hyperintense area observed during these initial days after NMDA lesion. The present study demonstrates that noninvasive MRI techniques, using a typical RARE sequence, offer a powerful tool for the early detection of neurotoxic lesion of the brain area, although some caution is required in its use for estimating the size of the lesioned area three days after its formation. The present findings indicate that, in long-term studies, alterations of the neighbouring structures, such as enlargement of the ventricular system, may confound the MRI evaluation of neurotoxic lesions in vivo.     

Warm sensitive neurons of the preoptic area regulate ambient temperature related changes in sleep in the rat

Warm sensitive neurons (WSN) play a major role not only in body temperature regulation, but also in sleep regulation. The present study was undertaken to investigate the role of WSN of the preoptic area (POA) in mediating the ambient temperature (T(amb)) related changes in sleep. The effect of T(amb) changes on sleep and body temperature was studied in rats before and after destruction of WSN of the POA by local intracerebral injection of capsaicin. Though the rats preferred 27 degrees C T(amb), they slept maximum at 30 degrees C. After destruction of WSN of the POA, slow wave sleep (SWS) peak was brought down to 27 degrees C, which was the preferred T(amb) of the rats. This indicates that WSN of the POA mediate the increase in SWS, at temperatures higher than preferred T(amb). On the other hand, in WSN destroyed rats, rapid eye movement (REM) sleep was maximum at 33 degrees C. It suggests that the REM sleep generation is under inhibitory control of the WSN of the POA. The study supports several earlier reports that the neurons of the POA play a key role in coordinating sleep and body temperature regulation.     

Association of blood lipids with Alzheimer's disease: A comprehensive lipidomics analysis

Introduction

The aim of this study was to (1) replicate previous associations between six blood lipids and Alzheimer's disease (AD) (Proitsi et al 2015) and (2) identify novel associations between lipids, clinical AD diagnosis, disease progression and brain atrophy (left/right hippocampus/entorhinal cortex).

Late-onset obsessive-compulsive disorder: the role of stressful life events

The onset of obsessive-compulsive disorder (OCD) for the first time in old age is uncommon and has been mostly related to cerebral abnormalities. We report a case of late-onset OCD in a 77-year-old woman following stressful life events but with a normal cerebral structure. The contribution of life events and vulnerability factors on the genesis and the presentation of her illness are discussed in relation to the literature on OCD.