ABSTRACT
In the developing nervous system, axons navigate through complex terrains that change depending on when and where outgrowth begins. For instance, in the developing cochlea, spiral ganglion neurons extend their peripheral processes through a growing and heterogeneous environment en route to their final targets, the hair cells. Although the basic principles of axon guidance are well established, it remains unclear how axons adjust strategies over time and space. Here, we show that neurons with different positions in the spiral ganglion employ different guidance mechanisms, with evidence for both glia-guided growth and fasciculation along a neuronal scaffold. Processes from neurons in the rear of the ganglion are more directed and grow faster than those from neurons at the border of the ganglion. Further, processes at the wavefront grow more efficiently when in contact with glial precursors growing ahead of them. These findings suggest a tiered mechanism for reliable axon guidance.
Subject(s)
Cochlea/cytology , Cochlea/embryology , Neuroglia/cytology , Spiral Ganglion/cytology , Animals , Axon Guidance/physiology , Basic Helix-Loop-Helix Transcription Factors/genetics , Cell Movement , Female , Mice, Transgenic , Nerve Tissue Proteins/genetics , Neurites/physiology , Neuroglia/physiology , Neurons/cytology , Neurons/physiology , Organ Culture Techniques , Pregnancy , Spiral Ganglion/physiology , Time-Lapse ImagingABSTRACT
BACKGROUND: Malaria is of global health concern particularly among pregnant women. Nigeria contributes largely to global burden but coverage of Intermittent Preventive Treatment of malaria in pregnancy using Sulphadoxine pyrimethamine remains low. This study was conducted to determine the national situation of missed opportunity for IPTp-SP and attempted to look at correlates and predictors. METHOD: The study used secondary data analysis of the Nigeria Demographic Health Survey, 2013. Data on socio-demographics, ANC characteristics and IPTp-SP use during pregnancy among 6,910 women aged 15-49 years who delivered in the last two years with at least 4 ANC visits were analyzed. Missed opportunity for IPTp delivery was defined as an ANC visit where IPTp was not delivered as per the policy. Data was analyzed using SPSS version 21. Associations used Chi-square test and significant variables were fit into multi-variate logistic regression model. All analyses were performed at 5% level of significance. RESULTS: National prevalence for missed opportunity for IPTp-SP was high (73.4%). Predictors of missed opportunity are being of poorer, middle and richer wealth index (OR=0.737, CI 0.566-0.960); (OR=0.659, CI 0.521-0.833); (OR=0.686, CI 0.550-0.857), residence in South East OR=0.549, CI (0.415-0.726) and in the North West (OR=0.176, CI 0.133-0.232). Other predictors are having a primary and secondary education and presenting for the first ANC visit in the second trimester OR=0.739, p=0.024, CI (0.569-0.961). CONCLUSION: Missed opportunity for IPTp-SP was high. The need for stronger governmental commitment to upscale uptake of IPTp-SP by incorporating the knowledge of socio-economic, cultural and demographic barriers to accessing IPTp is paramount.
ABSTRACT
In 44 Nigerians with heart muscle disease, the percentage of patients who had a fourfold rise or fall to at least one of the Coxsackie B viruses was greater than controls. Patients with heart muscle disease also had significantly higher levels of antibody titres. Antibodies to Coxsackie viruses B2, B3 and B6 were more frequent in their sera than in controls. While these results do not prove a Coxsackie B viral aetiology it is concluded that these viruses could be the cause of cardiac damage and heart failure in some Nigerians. It could also be one of the many adverse factors which produce repeated myocardial damage and thus weaken the heart to the point of failure.