Comparative Study of Variola and Varicella in Nigeria

1. Variola and varicella have been known for centuries in Nigeria, though not differentiated as separate entities. 2. Variolisation was practised by some of the tribes. 3. Isolation in the bush far from human dwellings is the general rule observed by most of the tribes. Cases are treated only by the smallpox priest or by someone who has had a previous attack. The same applies to handling of corpses, which are invariably denied burial rites. 4. Difficulties in diagnosis may be met with not only in relation to diseases like typhoid, influenza, pneumonia, measles, but also in relation to diseases like malaria, yellow fever and papular syphilides, which are common. 5. Stress is laid on the careful examination of all skin rashes in the Negro, and the isolation of any doubtful case. 6. The presence of a dark pigmented centre in variola papules is of valuable diagnostic importance when seen. 7. Variola and varicella are diseases of the hot months when people are least likely to crowd together. Fly prevalence, increased facilities for communication between neighbouring villages, aerial convection, and the effect of heat and sunlight on vaccine lymph and vaccination during the hot season are responsible factors for this seasonal incidence. 8. The incidence of variola is higher in African males than females. An even higher incidence of varicella in males is observed. This is due to a greater measure of natural immunity to both diseases in African women than is enjoyed by the men. 9. Variola is not selective as to age. All ages are almost equally affected, though, on account of vaccination, the incidence is now shifted to adult life. Varicella, in contrast, is selective as to age. In cold and temperate climates it is a disease of childhood, but in Nigeria,and probably in other tropical countries, it is a disease of adult life. The immunity enjoyed in childhood is closely related to the high natural immunity in African women. This immunity gradually passes off till it is at a minimum in adult life, when the incidence of varicella is highest. 10. The evolution of the eruption in the Negro is slow, and this is probably related to the texture and pigmentation of the skin

Bit error rate analysis of different digital modulation schemes in orthogonal frequency division multiplexing systems

This study presents the design of an orthogonal frequency division multiplexing (OFDM) system and analyses the performance of the different digital modulation techniques employed in the system. The OFDM system was modelled and different modulation schemes: M-ary phase shift keying (M-PSK) and M-ary quadrature amplitude modulation (M-QAM) were employed over two different channels: additive white Gaussian noise (AWGN), and Rayleigh multipath fading channels. Bit error rate (BER) analysis was carried out for the different digital modulation schemes over the two channels, and the number of fast Fourier transform (FFT) points used during the transmission was examined. Generally, results showed that over both AWGN and Rayleigh fading channels, lower order modulation schemes perform better than the higher order schemes. This comes at the detriment of the data rate, as lower order schemes have lower data rates compared with their higher order counterparts. In addition, it was observed that the system performed better over AWGN channel than Rayleigh fading channel for all modulation schemes used. On the number of FFT points used during the transmission, findings revealed that the performance of the system is more or less not really affected by the number of FFT points employed during transmission.Key words: Digital modulation, bit error rate, orthogonal frequency division multiplexing, additive white Gaussian noise, modulation schemes, fast Fourier transform

Preliminary experience in the management of tracheobronchial foreign bodies in Lagos, Nigeria

Aspiration of tracheobronchial foreign bodies commonly affects young children, is potentially life threatening and requires early intervention for extraction. Access to facilities and skill manpower for bronchoscopic extraction is however limited in Nigeria. The aim of this study is to describe the experience in our institution with bronchoscopic removal of tracheobronchial foreign bodies and highlight the challenges encountered. This is a retrospective study of all patients referred to the Lagos State University Teaching Hospital with a diagnosis of tracheobronchial foreign body within the period of February 2008 and February 2013. Data extracted from the medical records were age, sex, time interval between aspiration and presentation, location of tracheobronchial foreign body, bronchoscopic technique, complications and outcome. A total of 24 patients were referred and confirmed at bronchoscopy to have tracheobronchial foreign bodies. Mean age was 6.6 + 5 years. Male to female ratio was 1:1. Delayed presentation was common with 22 patients (91.7%) presenting more than 24 hours after aspiration. Aspirated material was inorganic in 17 patients (70.8%) and organic in 7 patients (29.2%). Location of tracheobronchial foreign bodies was right main bronchus in 16 patients (66.7%), left main bronchus in 6 patients (25%) and the trachea in 2 patients (8.3%). Challenges to speedy and safe removal of the foreign bodies were delayed presentation and a limited range of bronchoscopic equipment early in the series which caused prolonged procedures and increased complications. Two mortalities occurred early in the series; one from airway obstruction and the other from respiratory failure caused by tracheobronchial oedema. Extraction of tracheobronchial foreign bodies was faster, more complete and safer later in the series due to a wider range of bronchoscopy equipment which included both flexible and rigid videobronchoscopy with the use of optical forceps. This preliminary experience suggests that an adequate armamentarium of bronchoscopy equipment is required to increase the chances of complete extraction, speed up the procedure and reduce the risk of complications of Tracheobronchial Foreign Bodies in our environment. Delayed presentation increases the difficulty of the procedure so earlier referral of these patients would help reduce the risk involved in  their management.Key words: Bronchoscopy, Tracheobronchial Foreign Bodies, Lagos, Nigeri

Biochemical changes associated with sickle cell anaemia

Some blood chemical parameters including some enzyme activities were determined in forty two sickle cell patients in Ekiti state, Nigeria. All the parameters of interest analyzed for were found present in all the samples. The mean values for uric acid (0.35±0.16 mol/l), creatinine (100.55±8.13 μmol/l), urea (10.50±6.28 mmol/l), Total bilirubin (14.42±2.03 μmol/l), conjugated bilirubin (10.53±2.67 μmol/l), alkaline phosphatase (82.67±10.87 μ/l) aspartate transaminase (SGOT)(20.68±9.85 μ/l) and alanine transaminase (SGPT)(28.68±9.85 μ/L) were significantly higher (P 0.05). The significant raised level of SGPT, SGOT, ALP, total bilirubin, conjugated bilirubin, and significant lower levels of total protein, albumin, calcium, inorganic phosphate indicates that there may be abnormal liver and renal function as well as muscular and bone dysfunction in these patients

Experimental Validation of a Best-Fit Model for Predicting Radio Wave Propagation through Vegetation

In this study, a model for predicting radio wave propagation through vegetation at 900 and 1800MHz is proposed. An integrated model comprising of ground and foliage induced effects is evaluated with respect to experimental data obtained through drive test in and around a vegetation environment, using Test Mobile System (TEMS) investigation tools. Measured path loss was compared against predictions made by four empirical vegetation models. Results indicate that the European Cooperation in Science and Technology (COST) 235 model gives the best prediction and compare favourably with measured path loss in areas where vegetation is dominant. Although, this model showed the most accurate prediction of foliage loss in the investigated area, there is a need to modify it for enhanced signal prediction. The modified model was found to predict the measured path loss with Root Mean Square Errors (RMSEs) of 6.98dB and 10.00dB at 900 and 1800MHz, respectively. Overall, findings revealed that these RMSEs are within the acceptable range of up to 15.00dB, for quality signal prediction in related environment

Microalbuminuria, Other Markers of Nephropathy and Biochemical Derangements in Type 2 Diabetes Mellitus: Relationships and Determinants

Background: Microalbuminuria is an early indicator of Diabetic nephropathy and cerebrovascular disease.Objective: To evaluate relationships between microalbuminuria and other predictors of morbidity and mortality in type 2 DM.Methods: Fifty type 2 diabetic subjects were recruited each for three groups separated by disease durations. Thirty non-diabetic subjects were recruited to control each group. Urine albumin-to-creatinine ratio (ACR) was estimated. Fasting plasma glucose (FPG), serum creatinine, urea, total cholesterol (TC), triglycerides (TG), high- and low density lipoprotein (HDL, LDL) were measured.Results: The diabetics with longest disease duration of >10 years were the oldest (65.86±1.71), had highest systolic BP (147.12±3.39mmHg) and least BMI (27.20±0.71Kg/m2); they had poorest lipid control (TC:5.54±0.26mmol/L),though with the least TG (0.97±0.09mmol/L); they also had the most severe microalbuminuria (33.63±8.03g/L) and ACR (65.85±10.38mg/gm). Patients with diabetes of 5-10 years had the poorest glycaemic control:FPG- 7.82±0.47mmol/L; HbA1c-13.09±0.74%). Significant negative correlations exist between microalbuminuria,HBA1c(r=-2.28, p=0.028) and serum creatinine(r=-2.11,p=0.042) in patients with 5-10 years disease; a positive correlation between the ACR and TC(r=1.00,p<0.01) in those with >10 years disease. In multivariate analysis, independent predictors of microalbuminuria were disease duration (OR 2.2, p< 0.001); HBA1c (OR 7.3, p=0.02); LDL/HDL ratio (OR 13.4, p< 0.001).Conclusion: The severity and progression of albuminuria are associated with longer duration of diabetes and poor glycaemic control. Significant relationships exist between ACR and HBA1c, TC, HDL-C, TG, creatinine. Disease duration, ethnicity, HBA1c, TC, TG, HDL-C and LDL/HDL ratio are independent predictors of albuminuria.Keywords: diabetes, microalbuminuria, albumin-to-creatinine ratio, dyslipidaemia, nephropathy, cardiovascular diseaseFunding: None declare

Developing smart cities through optimal wireless mobile network

Wireless mobile communication has become the interconnecting technological platform through which seamless services of data, voice and other value added services can be deployed within local, national and global platforms. As a means to integrating smart services, the mobile network must be efficient in terms of coverage and quality of service. This paper therefore investigates large scale propagation models used to predict the signal strength with the aim of providing sufficient data required for radio frequency planning and optimization, which will engender flawless mobile network integration and consequent improved quality of service. Data analysis and optimization was carried out using Root Mean Square statistical tool for which the COST231 model was optimized to ensure proper mobile network planning and improved quality of service

Nasal Glioma: Prenatal Diagnosis and Multidisciplinary Surgical Approach

Nasal gliomas are congenital, nonmalignant rests of neuroglial tissue that typically present as a craniofacial mass. The differential diagnosis of such masses includes lesions that often require the involvement of various surgical subspecialties, including otolaryngology, neurosurgery, plastic surgery, and ophthalmology. Early surgical excision of these masses is advised to minimize nasal and craniofacial distortion. Accordingly, early diagnosis and management planning are paramount, and advances in prenatal imaging are creating a new role for obstetricians and radiologists in the initiation of diagnostic and therapeutic interventions. We describe the case history of a young patient found to have a craniofacial mass on routine prenatal ultrasound and subsequently managed with a multidisciplinary team approach

From caution to urgency: the evolution of HIV testing and counselling in Africa.

OBJECTIVE: To describe recent changes in policy on provider-initiated testing and counselling (PITC) for human immunodeficiency virus (HIV) infection in African countries and to investigate patients' experiences of and views about PITC. METHODS: A review of the published literature and of national HIV testing policies, strategic frameworks, plans and other relevant documents was carried out. FINDINGS: Of the African countries reviewed, 42 (79.2%) had adopted a PITC policy. Of the 42, all recommended PITC for the prevention of mother-to-child HIV transmission, 66.7% recommended it for tuberculosis clinics and patients, and 45.2% for sexually transmitted infection clinics. Moreover, 43.6% adopted PITC in 2005 or 2006. The literature search identified 11 studies on patients' experiences of and views about PITC in clinical settings in Africa. The clear majority regarded PITC as acceptable. However, women in antenatal clinics were not always aware that they had the right to decline an HIV test. CONCLUSION: Policy and practice on HIV testing and counselling in Africa has shifted from a cautious approach that emphasizes confidentiality to greater acceptance of the routine offer of HIV testing. The introduction of PITC in clinical settings has contributed to increased HIV testing in several of these settings. Most patients regard PITC as acceptable. However, other approaches are needed to reach people who do not consult health-care services