Assessing subacute mild traumatic brain injury with a portable virtual reality balance device

Purpose: Balance impairment is a common sensorimotor symptom in mild traumatic brain injury (mTBI). We designed an affordable, portable virtual reality (VR)-based balance screening device (Virtual Environment TBI Screen [VETS]), which will be validated relative to the Neurocom Sensory Organization Test (SOT) to determine if it can replace commonly used postural assessments.

Methods: This preliminary study examines healthy adults (n?=?56) and adults with mTBI (n?=?11). Participants performed six upright postural tasks on the VETS and the SOT. Analysis of variance was used to determine between-group differences. Pearson’s correlations were used to establish construct validity. Known-groups approach was used to establish classification accuracy.

Results: The mTBI cohort performed significantly worse than the healthy cohort on the new device (p?=?0.001). The new device has 91.0% accuracy and an ROC curve with a significant area-under-the-curve (AUC?=?0.865, p?p?=?0.034).

Conclusions: The new VR-based device is a valid measure for detecting balance impairment following mTBI and can potentially replace more expensive and cumbersome equipment. Assessments that test visual-vestibular processing, such as VETS, increase sensitivity to mTBI-related balance deficits, which can be used to guide rehabilitation.

• Implications for rehabilitation

• Emerging technology using virtual reality can be economically integrated into the clinical setting for easy testing of postural control in neurologically impaired populations.

• Tailoring postural assessments to include tasks that rely on visual and vestibular integration will increase the accuracy of detecting balance impairment following mild traumatic brain injury.

     

Antibodies to Plasmodium falciparum antigens and the risk of clinical malaria in endemic populations

As the research for the development of a malaria vaccine becomes increasingly important, a thorough understanding of the protection afforded by antibodies against parasite antigens is essential. The factors affecting the protective ability of antibodies elicited by highly immunogenic malaria parasite antigens and their interaction have been investigated in a study of Ugandan children by Greenhouse and colleagues. Their interesting finding of the effect of prior exposure on the protection provided against symptomatic malaria and the importance of the results in the immuno-epidemiological studies are discussed in this article.     

Enhanced sensitivity to drug-induced QT interval lengthening in patients with heart failure due to left ventricular systolic dysfunction

Patients with heart failure (HF) are at increased risk for drug-induced torsades de pointes (TdP) due to unknown mechanisms. Our objective was to determine if sensitivity to drug-induced QT interval lengthening is enhanced in patients with HF. In this multicenter, prospective study, 15 patients with atrial fibrillation or flutter requiring conversion to sinus rhythm were enrolled: 6 patients with New York Heart Association class II to III HF (mean ejection fraction [EF], 30% ± 9%), and 9 controls (mean EF, 53% ± 6%). Patients received ibutilide 1 mg intravenously. Blood samples and 12-lead electrocardiograms were obtained prior to and during 48 hours postinfusion. Serum ibutilide concentrations at 50% maximum effect on Fridericia-corrected QT (QT(F)) intervals (EC(50)) were determined, and areas under the effect (QT(F) interval vs time) curves (AUECs) were calculated. Ibutilide concentration-QT(F) relationships were best described by a sigmoidal E(max) model with a hypothetical effect compartment. Median [interquartile range] AUEC from 0 to 4 hours was larger in the HF group than in controls (1.86 [1.86-1.93] vs 1.82 [1.81-1.84] s·h; P = .04). Median EC(50) was lower in the HF group (0.48 [0.46-0.49] vs 1.85 [1.10-3.23] μg/L; P = .008). Sensitivity to drug-induced QT interval lengthening is enhanced in patients with systolic HF, which may contribute to the increased risk of drug-induced TdP.     

Effect of Community-Based Functional Aerobic Training on Motor Performance and Quality of Life of Children with Spastic Cerebral Palsy

BackgroundEfficacies of community-based exercise programmes have been well reported but there is scarce information on the expediency of community-based rehabilitation in a society where many of children with disabilities live in poorly resourced settings with extremely limited rehabilitative services. The study investigated the effects of community-based functional aerobic exercise (CBFAE) on gross motor function, walking distance, and quality of life of children with cerebral palsy (CP).MethodsQuasi-experimental design was used. Children with gross motor function classification system (GMFCS) levels I – II participated in eight weeks CBFAE training four times/week, 50 minutes/day at 40–80% maximum heart rate. Gross motor function (GMF), walk distance and quality of life were assessed pre and post CBFAE training.ResultsSignificant improvement observed in GMF (Dstanding) (8.2%, P=.000), GMF (E-walking+running+jumping (5.12%, P=.004), walking distance (6.09%, P=.009). Higher significant positive effects of CBFAE observed in Social wellbeing and acceptance (107.10%, P=.000), and participation and physical health (105.04%, P=.005) by children parent proxy. Self-reported results showed that for CBFAE, significant positive improvements were higher in Pain and impact of disability (67.93%, P=.049) and Participation and physical health (60.00%, P=.042).ConclusionCBFAE training contributes majorly to improved standing, walking, jumping and running and selfesteem, quality of life of children with spastic CP. Clinicians and exercise therapists should essentially incorporate CBFAE training and activities into the management of children with CP for improved mobility and functional performances.     

Synthesis, structure, and biocompatibility of pulsed laser-deposited TiN nanowires for implant applications

A bottom-up based pulsed laser deposition technique has been used to grow titanium nitride (TiN) nanowires on single crystalline substrates. The first step of this method is the dissolution of laser ablated gaseous TiN material in the nanodimensional catalytic gold (Au) liquid islands located on the substrate surfaces. The continuous dissolution of TiN results in the supersaturation of liquid Au with TiN followed by extrusion of solid TiN material in the nanowire form at the liquid/solid interface. The growth of TiN nanowires continues as long as its dissolution rate into the catalyst Au matches the extrusion rate of solid TiN. This bottom-up approach gives rise to a one-dimensional TiN nanowire structures (length: 200-300 nm and diameter: 20-30 nm) capped with Au. The ascent of Au nanodots to the top of TiN nanowires can be explained based on breaking of weaker bonds and building of stronger bonds. The TiN nanowires are provided vertical alignment by selecting a plane of the substrate that provides the least lattice mismatching to the (111) plane of TiN which has lower surface energy than its other planes: (100) or (110). After the successful formation and structural characterization, a lactate dehydrogenase (LDH) release assay has been used to confirm the biocompatibility and cytotoxicity of these nanowires.     

Comparative efficacy of antimalarial drugs including ACTs in the treatment of uncomplicated malaria among children under 5 years in Ghana

The emergence and spread of Plasmodium falciparum resistance to commonly used antimalarials such as chloroquine and sulphadoxine/pyrimethamine poses major challenges to malaria control in sub-Saharan Africa. We undertook a study on the efficacy of some antimalarial drugs in 2003 with the view of supporting the National Malaria Control Programme in the review of the antimalarial drug treatment policy in Ghana. Children aged 6-59 months with signs/symptoms of uncomplicated malaria including axillary temperature > or =37.5 degrees C; mono infection with P. falciparum; and parent's willingness to give consent, were randomized into four treatment groups and followed up for a maximum of 28 days. The treatment groups were chloroquine (CHQ), sulphadoxine/pyrimethamine (SP), amodiaquine+artesunate (ADQ+ART) combination, and artemether+lumefantrine (Coartem) combination. Clinical evaluation of 168 children studied showed that cumulative pcr-corrected cure rates on day 28 were 100% for ADQ+ART; 97.5% for coartem, 60% for SP and 25% for CHQ. The artemisinin-based combinations effected rapid fever and parasite clearance. Prevalence of gametocytaemia was highest in the SP group whilst the CHQ group did not show any significant changes in haemoglobin levels during the follow-up period. The findings are in agreement with current recommendations for using artemisinin-based combinations for treating uncomplicated malaria in areas of high CHQ failure such as Ghana.     

Chronic non-communicable diseases and the challenge of universal health coverage: insights from community-based cardiovascular disease research in urban poor communities in Accra,Ghana

Background

The rising burden of chronic non-communicable diseases in low and middle income countries has major implications on the ability of these countries to achieve universal health coverage. In this paper we discuss the impact of cardiovascular diseases (CVD) on primary healthcare services in urban poor communities in Accra, Ghana.

Methods

We review the evidence on the evolution of universal health coverage in Ghana and the central role of the community-based health planning services (CHPS) programme and the National Health Insurance Scheme in primary health care. We present preliminary findings from a study on community CVD knowledge, experiences, responses and access to services.

Results

The rising burden of NCDs in Ghana will affect the achievement of universal health coverage, particularly in urban areas. There is a significant unmet need for CVD care in the study communities. The provision of primary healthcare services for CVD is not accessible, equitable or responsive to the needs of target communities.

Conclusions

We consider these findings in the context of the primary healthcare system and discuss the challenges and opportunities for strengthening health systems in low and middle-income countries.

     

HLA-DRB1*04 allele is associated with severe malaria in northern Ghana

Several associations between specific HLA alleles and susceptibility or resistance to Plasmodium falciparum malaria have been previously reported, but no associations have been confirmed in multiple populations. We studied associations between HLA-A, -B, and DRB1 alleles and severe malaria in northern Ghana. We analyzed HLA-DRB1*04 in 4,032 subjects from a severe malaria case-control study, 790 severe malaria cases, 1,611 mild malaria controls, and 1631 asymptomatic controls. The presence of HLA-DRB1*04 was associated with severe malaria (OR = 2.42, 95% CI = 1.64, 3.58). The allele frequency of DRB1*04 was similar in the two major ethnic groups in the study population, Kassem (4.4%) and Nankam (4.7%), and the OR for the association between DRB1*04 and severe malaria was similar in both ethnic groups. These findings are consistent with results from Gabon suggesting that DRB1*04 is a risk factor for severe malaria.     

Lipophilic Statin Versus Rosuvastatin (Hydrophilic) Treatment for Heart Failure: a Meta-Analysis and Adjusted Indirect Comparison of Randomised Trials

Objectives

This study aims to compare lipophilic and hydrophilic statin therapy on clinical outcomes of heart failure (HF) using a systematic review and an adjusted indirect comparison meta-analysis. Outcomes were all-cause mortality, cardiovascular mortality, cardiovascular hospitalization and hospitalization for worsening HF.

Methods

We conducted a search of PubMed, EMBASE and Cochrane databases until 31st December 2014 for randomized control trials (RCTs) in HF evaluating statins versus placebo. Identified RCTs and their respective abstracted information were grouped according to statin type evaluated and analyzed separately. Outcomes were initially pooled with the Peto’s one-step method, producing odd ratios (OR) and 95 % confidence intervals (CI) for each statin type. Using these pooled estimates, we performed adjusted indirect comparisons of lipophilic versus hydrophilic statin for each outcome.

Results

Thirteen studies involving 10,966 patients were identified and analyzed. Lipophilic statins were superior to hydrophilic rosuvastatin regarding all-cause mortality (OR 0?·?50; 95 % CI, 0?·?11–0?·?89; p?=?0?·?01), cardiovascular mortality (OR 0?·?61; 0?·?25–0?·?97; p?=?0?·?009), and hospitalization for worsening HF (OR 0?·?52; 0?·?21–0?·?83; p?=?0?·?0005). However, both statins were comparable with regards to cardiovascular hospitalization [OR 0?·?80 (0?·?31, 1?·?28); p?=?0?·?36].

Conclusions

Lipophilic statin treatment shows significant decreases in all-cause mortality, cardiovascular mortality and hospitalization for worsening HF compared with rosuvastatin treatment. This meta-analysis provides preliminary evidence that lipophilic statins offer better clinical outcomes in HF till data from head to head comparisons are available.

     

Detection of malaria sporozoites by standard ELISA and VecTestTM dipstick assay in field-collected anopheline mosquitoes from a malaria endemic site in Ghana

We compared the VecTestTM dipstick assay for detection of Plasmodium sporozoites in Anopheles vectors of malaria with standard circumsporozoite (CS) microplate ELISA for detection of Plasmodium falciparum circumsporozoite protein (PfCSP) in Anopheles mosquitoes. Mosquitoes were collected from a malaria endemic site (Kassena Nankana district) in northern Ghana. Of 2620 randomly sampled mosquitoes tested, the standard CS-ELISA gave a sporozoite rate of 10.8% compared with 11.2% by VecTestTM, which was not statistically different (P = 0.66). Visual reading of the CS-ELISA results gave a sporozoite rate of 13.4%, which was higher than the other tests (P > 0.05). To allow a more objective evaluation of the sensitivity of the dipstick, an additional 136 known CS-ELISA-positive specimens were analysed. The prevalence of the test (including the additional samples) was 14.6% and 14.7% for CS-ELISA and dipstick, respectively (P > 0.05). The estimated prevalence by visual assessment of the CS-ELISA results was 17.5%. The relative specificity and sensitivity of the VecTestTM dipstick and visually read ELISA were estimated based on the CS-ELISA as a gold standard. The specificities of the dipstick and visual ELISA were high, 98.0% and 96.6%, respectively. However, the sensitivities of the two assays were 88.8% for VecTest and 100% for visual ELISA (P < 0.01). Concordance between VecTest and CS-ELISA was good (kappa = 0.86). Similarly, there was a good concordance between the dipstick and the visually read ELISA (kappa = 0.88). Extrapolating from PfCSP controls (titrated quantities of P. falciparum sporozoites), mean sporozoite loads of CS-ELISA-positive An. gambiae (286 +/- 28.05) and An. funestus (236 +/- 19.32) were determined (P = 0.146). The visual dipstick grades showed high correlation with sporozoite load. The more intense the dipstick colour, the higher the mean sporozoite load (+ = 108, ++ = 207, +++ = 290, r = 0.99, r2 = 1). The VecTest dipstick offers practical advantages for field workers needing rapid and accurate means of detection of sporozoites in mosquitoes.