Synthesis and Characterization of Hexadecylamine Capped ZnS, CdS, and HgS Nanoparticles Using Heteroleptic Single Molecular Precursors

Zn(II), Cd(II), and Hg(II) complexes of tetramethyl thiuram disulfides and 1-ethoxylcarbonyl-1-ethylenecarbonyl-2-dithiolate were synthesized and characterized by elemental analysis, FTIR, and 1H- and 13C-NMR spectroscopy. The complexes were thermolysed in hexadecylamine as single molecule precursors to prepare HDA capped ZnS, CdS, and HgS nanoparticles. The optical and structural properties of the nanoparticles are reported. ZnS nanoparticles existed in the hexagonal phase with particle sizes of 8–15 nm; the CdS nanoparticles in the cubic phase have particle sizes in the range 4–7 nm and the HgS nanoparticles indexed to face-centered cubic phase have an average particle size of 7–12 nm

Effects of vigabatrin, carbamazepine or its combination on the pituitarygonadal axis in male Wistar rats

Objectives: Epilepsy is the most common non-infectious neurologic disease in developing African countries following stroke and Alzheimer's disease. Most conventional antiepileptic drugs, due to their centrally acting potentials have been implicated in the deregulation of reproductive hormones. This study assessed the effect of the single and combined administration of vigabatrin (VIG) and carbamazepine (CBZ) on the pituitary-gonadal axis of male Wistar rats.Methods: Fifty male Wistar rats were randomly divided into 5 groups (n=10). The animals were administered with distilled water (0.1 ml/kg/day), VIG (200 mg/kg/day), CBZ (200 mg/kg/day), VIGCBZ combination (100 mg/kg/day each) and VIG-CBZ combination (200 mg/kg/day each) for 8 weeks. Twenty-four hours after the last dose, 5 rats from each group were sacrificed, while the remaining 5 eventually sacrificed after another 8 week of drug withdrawal. The level of luteinizing hormone, follicle stimulating hormone and testosterone were determined from the serum. The weight of the reproductive organs and sperm indices were assayed, while the testicular tissue were examined for signs of histological alteration.Results: The results showed significant decrease in the levels of luteinizing hormone, follicle stimulating hormone, testosterone and sperm physiological indices. Morphological alteration was noticed in the testes of all the treated rats. However, there was restoration of these parameters sequelae to 8 weeks cessation of treatment.Conclusion: Single and combined administration of VIG and CBZ resulted into pituitary-gonadal axis hormonal deregulation and alterations in the sperm profile which were however reversible upon cessation of treatment.Keywords: epilepsy, vigabatrin, carbamazepine, sperm, testosteron

Rapid Assessment of Cataract Blindness Among Ughelli Clan in an Urban/Rural District of Delta State, Nigeria

Background: A population based, rapid assessment for cataract blindness was conducted in Ughelli North local government area of DeltaState, an urban/rural area of Nigeria between June and July 2001 with the aim of establishing baseline data for developing cataract intervention services for the area. Method: A cluster random sampling method was used based on the guidelines for the Rapid Assessment for Cataract Surgery. A total of 8 clusters of 90 persons were randomly selected from the 8 communities that make up the Ughelli clan. Only people of 50 years and above who had been resident in the area for up to six months were included. A total of 684 persons were examined (91.2% coverage) using a designed survey form. The barriers to the uptake of cataract surgery were also identified during the survey. The WHO definitions of blindness and visual impairment according to visual acuity were used as criteria for classification of visual blindness and visual impairment. Results: The prevalence of bilateral cataract blindness (cataract causing visual acuity of less than 3/60 in the better eye) for people of 50 years and above was 4.1% (95% CI: 2.96 to 5.24%) with cataract accounting for 41.2% of all the blindness in this age group. Prevalence of cataract blindness was higher in females than in males (5.0% versus 3.6%) About 80% of the cataract blindness occurs in people of 70 years and above. The cataract surgical coverage for eyes was 4.5%; cataract surgical coverage for couching was 18.2%. The major barriers to the uptake of cataract surgical services were lack of awareness of eye care services in nearby district (71.0%), the imagined high cost of the services (17.9%) the perception of women that their health problems are not of immediate importance (7.1%). Conclusion:At the time of study about 2000 person required immediate cataract surgery in the area. With an estimated incidence of 400 new cases per year, there is a need to set up cataract surgical services in the Ughelli North local government area. Special attention should be given to reduction of cataract blindness in females.Introduction : Evaluation rapide, bas\ue9e sur une population de la c\ue9cit\ue9 provoqu\ue9e par une cataracte a \ue9t\ue9 effectu\ue9e dans l'administration locale du nord d'Ughelli de l'\uc9tat de Delta, une zone urbaine/rurale du Nig\ue9ria entre juin et juillet 2001 dans le but d'\ue9tablir des donn\ue9es de base pour le d\ue9veloppement du service d'intervention chirurgicale de la cataracte pour la r\ue9gion. M\ue9thode : Une m\ue9thode d'un groupe d'\ue9chantillonage au hasard a \ue9t\ue9 utilis\ue9e bas\ue9e sur des directives pour l'Evaluation Rapide pour l'intervention chirurgicale de la Cataracte. Un nombre total de 8 groupes compos\ue9s de 90 personnes ont \ue9t\ue9 s\ue9lectionn\ue9s au hasard parmi les 8 communaut\ue9s dont le clan d'Ughelli est compos\ue9. Un nombre total de 684 personnes ont \ue9t\ue9 examin\ue9es soit 91,2% traitement \ue0 travers l'utilisation d'un formulaire con\ue7u pour faire un sondage. R\ue9sultats : La fr\ue9quence de la c\ue9cit\ue9 de la cataracte bilat\ue9rale (la cataracte qui provoque une acuit\ue9 visuelle de moins de 3/60 dans le meilleur oeil) pour des peuples de 50 ans et plus \ue9tait 4,1% soit 95% CL : 2,96 au 5,24%) dont la cataracte constitue 41,2% de toute les c\ue9cit\ue9s dans cette tranche d'\ue2ge. La fr\ue9quence de la c\ue9cit\ue9 de la cataracte \ue9tait \ue9lev\ue9e chez le sexe f\ue9minin plus que chez le sexe masculin (5,0% contre 3,6%) Environ 80% de la c\ue9cit\ue9 de la cataracte arrivent chez des gens \ue2g\ue9s de 70 ans et plus. Les traitements \ue0 travers l'intervention chirurgicale de la cataracte pour des yeux \ue9tait 4,5%. Les traitements pour l'intervention chirurgicale pour le couching contitue 18,2%. Les barri\ue8res principales contre les services d'intervention chirurgicale de la cataracte \ue9taient manque de l'opinion publique sur la conscience de services de soins des yeux dans la r\ue9gion d'\ue0 c\uf4t\ue9 (71,0%), le soi-disant services \ue0 grands frais, (17,9%), la conception des femmes que les probl\ue8mes r\ue9latifs \ue0 leurs sant\ue9 n'est pas d'urgence (7,1%). Conclusion : Pendant cette \ue9tude, environ 2000 personnes avaient besoin de l'intervention chirurgicale de la cataracte d'urgence dans cette r\ue9gion. Avec une fr\ue9quence d'environ 400 nouveaux cas chaque ann\ue9e, c'est n\ue9cessaire de cr\ue9er un service d'Intervention Chirurgicale de la Cataracte dans l'administration locale du nord d'Ughelli. Une attention particuli\ue8re devrait \ueatre port\ue9e sur la reduction de la c\ue9cit\ue9 de la cataracte chez des femmes

Clinical profile of parkinsonism and Parkinson's disease in Lagos, Southwestern Nigeria

<p>Abstract</p> <p>Background</p> <p>Current data on the pattern of parkinsonism and Parkinson's disease in Nigerians are sparse.</p> <p>This database was designed to document the clinical profile of PD in Nigerians, and compare this to prior observations.</p> <p>Methods</p> <p>A database of patients presenting to the Neurology out-patients clinic of the Lagos University Teaching Hospital was established in October 1996. Demographic and clinical data at presentation (disease stage using Hoehn and Yahr scale; 'off' state severity on the Unified Parkinson's disease Rating Scale) were documented for patients diagnosed with parkinsonism between October 1996 and December 2006. Cases were classified as Parkinson's disease or secondary parkinsonism (in the presence of criteria suggestive of a secondary aetiology).</p> <p>Results</p> <p>The hospital frequency of parkinsonism (over a 2-year period, and relative to other neurologic disorders) was 1.47% (i.e. 20/1360). Of the 124 patients with parkinsonism, 98 (79.0%) had PD, while 26 (21.0%) had secondary parkinsonism. Mean age (SD) at onset of PD (61.5 (10.0) years) was slightly higher than for secondary parkinsonism (57.5 (14.0) years) (P = 0.10). There was a male preponderance in PD (3.3 to 1) and secondary parkinsonism (2.7 to 1), while a positive family history of parkinsonism was present in only 1.02% (1/98) of PD. There was a modestly significant difference in age at onset (SD) of PD in men (60.3 (10.4)) compared to women (65.2 (7.9)) (T = 2.08; P = 0.04). The frequency of young onset PD (≤ 50 years) was 16.3% (16/98). The mean time interval from onset of motor symptoms to diagnosis of PD was 24.6 ± 26.1 months with majority presenting at a median 12 months from onset. On the H&Y scale, severity of PD at presentation was a median 2.0 (range 1 to 4). PD disease subtype was tremor-dominant in 31 (31.6%), mixed 54 (55.1%) and akinetic-rigid 14 (14.3%). Hypertension was present as a co-morbidity in 20 (20.4%), and diabetes in 6 (6.12%).</p> <p>Conclusions</p> <p>The clinical profile of PD in Nigerians is similar to that in other populations, but is characterized by delayed presentation as has been reported in other developing countries. Young-onset disease occurs but may be less commonly encountered, and frequency of a positive family history is lower than in western populations.</p

New onset neuromyelitis optica in a young Nigerian woman with possible antiphospholipid syndrome: a case report

<p>Abstract</p> <p>Introduction</p> <p>Devic's neuromyelitis optica is an inflammatory demyelinating disease that targets the optic nerves and spinal cord. It has a worldwide distribution and distinctive features that distinguish it from multiple sclerosis. There has been no previous report of neuromyelitis optica from our practice environment, and we are not aware of any case associated with antiphospholipid syndrome in an African person.</p> <p>Case presentation</p> <p>We report the case of a 28-year-old Nigerian woman who presented with neck pain, paroxysmal tonic spasms, a positive Lhermitte's sign and spastic quadriplegia. She later developed bilateral optic neuritis and had clinical and biochemical features of antiphospholipid syndrome. Her initial magnetic resonance imaging showed a central linear hyperintense focus in the intramedullary portion of C2 to C4. Repeat magnetic resonance imaging after treatment revealed resolution of the signal intensity noticed earlier.</p> <p>Conclusion</p> <p>Neuromyelitis optica should be considered in the differential diagnoses of acute myelopathy in Africans. We also highlight the unusual association with antiphospholipid syndrome. Physicians should screen such patients for autoimmune disorders.</p

Overexpression of Hydroxynitrile Lyase in Cassava Roots Elevates Protein and Free Amino Acids while Reducing Residual Cyanogen Levels

Cassava is the major source of calories for more than 250 million Sub-Saharan Africans, however, it has the lowest protein-to-energy ratio of any major staple food crop in the world. A cassava-based diet provides less than 30% of the minimum daily requirement for protein. Moreover, both leaves and roots contain potentially toxic levels of cyanogenic glucosides. The major cyanogen in cassava is linamarin which is stored in the vacuole. Upon tissue disruption linamarin is deglycosylated by the apolplastic enzyme, linamarase, producing acetone cyanohydrin. Acetone cyanohydrin can spontaneously decompose at pHs >5.0 or temperatures >35°C, or is enzymatically broken down by hydroxynitrile lyase (HNL) to produce acetone and free cyanide which is then volatilized. Unlike leaves, cassava roots have little HNL activity. The lack of HNL activity in roots is associated with the accumulation of potentially toxic levels of acetone cyanohydrin in poorly processed roots. We hypothesized that the over-expression of HNL in cassava roots under the control of a root-specific, patatin promoter would not only accelerate cyanogenesis during food processing, resulting in a safer food product, but lead to increased root protein levels since HNL is sequestered in the cell wall. Transgenic lines expressing a patatin-driven HNL gene construct exhibited a 2–20 fold increase in relative HNL mRNA levels in roots when compared with wild type resulting in a threefold increase in total root protein in 7 month old plants. After food processing, HNL overexpressing lines had substantially reduced acetone cyanohydrin and cyanide levels in roots relative to wild-type roots. Furthermore, steady state linamarin levels in intact tissues were reduced by 80% in transgenic cassava roots. These results suggest that enhanced linamarin metabolism contributed to the elevated root protein levels

Nigeria’s Relations with Her Neighbors and the Fight against Terrorism: An Analysis of the Multinational Joint Task Force

This chapter examines Nigeria’s relationship with her immediate neighboring countries in the fight against terrorism. It probed the challenges of national security following the internationalization of Boko Haram terrorist threats, particularly around the Lake Chad basin, and the responses of countries such as Cameroon, Chad, and Niger. These countries, like Nigeria, share borders around the Lake Chad and are the core contributors to the Multinational Joint Task Force (MNJTF). Nigeria is an English-speaking country (former British colony), while these other neighbors are historically French colonial territories. Hence, their political, cultural, military, and economic affinities are with France. The varying backgrounds have accounted for the challenges in the subregion including the Boko Haram insurgency and the efforts at military cooperation in tackling it. Consequently, these questions are examined: what factors led to the formation of MNJTF and what role has it played in the counterterrorism strategies of the country? In what ways has the nature of Nigeria’s relations with these countries impacted on the operation of the body? What are the roles of external powers such as France with her domineering influence on these countries in the war against terrorism and how has it promoted Nigeria’s national security interest? The chapter relies on documented materials to interrogate the questions and proffer necessary policy recommendations premised on the findings