Medicinal plants with cholinesterase inhibitory activity: A Review

Alzheimer’s disease (AD), a common neurodegenerative disease, is characterized by low levels in the brain of the neurotransmitter, acetylcholine (ACh). Clinical treatment of this disease is palliative and relies mostly on enhancing cholinergic function by stimulation of cholinergic receptors or prolonging the availability of ACh released into the neuronal synaptic cleft by use of agents which restore or improve the levels of acetylcholine. Inhibition of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), enzymes which breakdown acetylcholine, are considered as a promising strategy for the treatment of AD. A potential source of AChE and BChE inhibitors is provided by the abundance of plants in nature, and natural products continue to provide useful drugs and templates for the development of other compounds. The present work constitutes a review of the literature on 123 species of medicinal plants that have been tested for AChE inhibitory activity and 42 plant species which have been tested for BChE inhibitory activity. The plant species listed are potential cholinesterase inhibitors and may aid researchers in their study of natural products which may be useful in the treatment of AD.Key words: Alzheimer’s disease, acetylcholine, acetylcholinesterase, butyrylcholinesterase and medicinal plants

Extraction Of Fetal Electrocardiogram Using An Adaptive Neuro-Fuzzy System

In this paper, adaptive neuro fuzzy inference system (ANFIS) was used for the cancellation of maternal electrocardiogram (MECG) in fetal electrocardiogram extraction (FECG) from the composite abdominal electrocardiogram (AECG). This technique is used to estimate the MECG present in the abdominal signal of a pregnant woman. The FECG is then extracted by subtracting the estimated MECG from the abdominal signal. In the furtherance of extraction, MATLAB (version 7.6) was used to code the system in order to generate the maternal heartbeat signal and the fetal heartbeat signal which were added to form the measured signal. For the fetal heartbeat signal to be recovered from the interference (maternal heartbeat) signal, a reference signal (which is a clean version of the original maternal heartbeat signal) was introduced in the system. It is this signal that cancelled the maternal heartbeat signal in the measured signal, thereby leaving the fetal heartbeat signal as an error signal. However, though the recovered signal still contained some traces of the maternal heartbeat signal, performance of the soft computing technique applied is in terms of the capability of adaptive neuro fuzzy inference system in removing the overlapping between the MECG and the FECG signals. The results obtained show that this method is a simple and powerful means for the extraction of Fetal Electrocardiogram.   Keywords: Fetal Electrocardiogram Extraction (FECG), Neuro-fuzzy system, Noise Cancellatio

Impact of Tropospheric Scintillation Models on Earth-Space Path in Southwest, Nigeria

signals being attenuated by rain, cloud, gas and tropospheric scintillation. This paper present the impact of tropospheric scintillation on earth-space path in southwest, Nigeria at 12.245 GHz. Twenty-four months of scintillation data from ASTRA 2E/2F/2G on latitude 6.7° N and longitude 3.23° E for two years (2015-2016) were statistically analysed and compare with four existing models. The result reveals that under non-rainy atmosphere, ITU-R model gave the lowest percentage error of about 1.07%, followed closely by Karasawa model with 1.67%. The work also shows that ITU-R is the best fit model of tropospheric scintillation fade for the study area at 1% of time. A modified ITU- R scintillation fade model was also proposed for the tropical region of Ota and its environs

Evaluation of Refractivity Gradient and k-factor within the Lower Troposphere of Maiduguri and Enugu under Two Climatic Zones in Nigeria

Estimation of radio refractivity is important in the planning and design of terrestrial radio communication links for the availability and accessibility of strong networks and signals. This paper investigates the refractivity gradient, effective earth radius factor (k), and the geo-climatic factor K in the first 1km of the troposphere of two selected stations (Maiduguri and Enugu) under different climatic zones in Nigeria. The indirect method of measuring radio refractivity was employed in this study to take measurements over the two selected stations. Vertical profile values of pressure (hPa), Temperature (°C), and Relative humidity (%) within the first 1 km were extracted from MERRA MAIMCPASM V5.20 database profile obtained from a satellite sounding instrument by NASA in the United States. MatLab programming language was used to evaluate the refractivity gradient, k-factor, and geo-climatic factor using the equations recommended by ITU. The results showed that Enugu was predominantly sub-refractive due to the tropical savannah climate while Maiduguri encountered both sub-refractive and normal refractive conditions due to the hot semi-arid climate, and unstable and extreme weather conditions in the region

Successful pregnancy outcome after in vitro fertilisation following Pre-implantation Genetic Diagnosis/Polymerase Chain Reaction screening for single gene disorder (sickle cell anaemia) before embryo transfer: ...

A couple, both carriers of the sickle cell anaemia trait (Genotype HbAS) with an offspring already affected with the genetic disease underwent a Pre-implantation Genetic Diagnosis/ Polymerase Chain Reaction screening of biopsied blastomeres. DNA analysis of single blastomeres was carried out to find out indicated a viable intra-uterine pregnancy with embryos which carried the sickle cell mutation, which resulted in a livebirth (HbAS). PGD/PCR in combination with IVF appears to be the most suitable treatment plan for patients who are at a higher risk of reproducing offspring affected with inheritable genetic diseases.Keywords: PGD/PCR, Sickle cell anaemia, IVF, Biopsy, FE

Numerical Analysis of the Measured Temporal Rainfall Rate and Rain Attenuation in a Tropical Location

Extreme weather condition is one of the major challenges observed in the troposphere due to meteorological weather parameters such as rainfall. Rainfall causes severe attenuation to satellite communication at Ku band. This paper studied the numerical relationship between the calculated rain attenuation and the observed rain rate at Ku band for the tropical station based on a 12-month data measurement. This paper aims at presenting the proportional variation between rain rate and rain attenuation in the locality of interest. A tipping bucket rain gauge is used to obtain and analyse rain rate data. One-minute signal strength measurement were obtained and analysed. The 12-month data were obtained from January till December 2015. The result shows an average rain rate of about 237.0 mm/hr, 114.0 mm/hr, 38.0 mm/hr and 3.0 mm/hr and attenuation of 4.74, 4.25, and 3.59 and 2.66 dB/km at 12.245 GHz, respectively, for 0.001 %, 0.01% and 0.1% and 1 % of the time respectively for the combined values of rain rate and rain attenuation statistics. The result indicates a corresponding direct proportionality between the rain rate and rain attenuation

Numerical Analysis of the Measured Temporal Rainfall Rate and Rain Attenuation in a Tropical Location

Extreme weather condition is one of the major challenges observed in the troposphere due to meteorological weather parameters such as rainfall. Rainfall causes severe attenuation to satellite communication at Ku band. This paper studied the numerical relationship between the calculated rain attenuation and the observed rain rate at Ku band for the tropical station based on a 12-month data measurement. This paper aims at presenting the proportional variation between rain rate and rain attenuation in the locality of interest. A tipping bucket rain gauge is used to obtain and analyse rain rate data. One-minute signal strength measurement were obtained and analysed. The 12-month data were obtained from January till December 2015. The result shows an average rain rate of about 237.0 mm/hr, 114.0 mm/hr, 38.0 mm/hr and 3.0 mm/hr and attenuation of 4.74, 4.25, and 3.59 and 2.66 dB/km at 12.245 GHz, respectively, for 0.001 %, 0.01% and 0.1% and 1 % of the time respectively for the combined values of rain rate and rain attenuation statistics. The result indicates a corresponding direct proportionality between the rain rate and rain attenuation