The influence of fillers on theophylline release from clay matrices

Abstract: The objectives of this study were to investigate the suitability of magnesium aluminium silicate (MAS) (Veegum®) to control drug release of a model drug, theophylline, from tablet matrices. To this end, the performance of three commonly used fillers namely: lactose, microcrystalline cellulose (Avicel PH102; MCC), and pre-gelatinized starch, Starch 1500 PGS), were evaluated against Veegum®. The physico-mechanical properties of the tablet matrices were studied along with dissolution studies to determine the effect of single or binary mixtures of the excipients on the drug release pattern. A DSC hydration methodology was also employed to characterize the states of water present in the tablet matrices and to determine any impact on drug release. Formulations containing MAS alone produced compacts with the lowest hardness (4.5 kp) whereas formulations containing MCC alone produced the hardest tablets (17.2 kp). Dissolution studies suggested that matrices containing MAS alone released the theophylline quickest as compared to lactose, MCC or PGS. It was difficult to establish a trend of the bound and free water states in the tablet matrices; however the formulation containing only MAS had the highest bound water at 29 %. The results therefore show that theophylline does not interact with MAS. As such the dominant factor in controlling drug release using MAS requires interaction or intercalation with a cationic drug. In the absence of this however, other excipients can play a role in controlling drug release. Keywords: Veegum, clay matrices, DSC hydration, Magnesium aluminium silicate, filler

Assessment of Selected Dams in Kwara State, Nigeria

In Nigeria, more than 50% of the geographical area lies in the Savannah. Over time, this area has been vulnerable to the vagaries of periodic and severe droughts, affecting the survival of man and animals. Safe and economic design and construction of dams to store surplus river waters thus assumed greater urgency. However, dam failures and flood issues has caused catastrophic damages and losses of lives and properties. The uncertainties associated with deteriorating dams have necessitated proper and timely assessment and rehabilitation of these structures. This study identifies and investigates relapse in four (4) selected dams in Kwara State namely: Unilorin-, Malete-, Okuta- Oja- and Asa-dam. A series of field inspection was carried out and results obtained were analyzed. Amongst the four dams, Okuta-Oja dam displayed the worst case of relapse with seepages through the foundation and body of the dam. About 20 baffle blocks out of 30 have been damaged in Unilorin dam, while Malete dam was undergoing re-construction owing to seepage failure. Asa dam however remains intact with no physical and structural defect. Unless appropriately handled, ageing and relapsing infrastructural systems can pose a significant problem, threatening economic prosperity and public safety. Thus, monitoring the state of dam structures to ensure timely maintenance is critically important to preventing catastrophic disasters

The Challenges of Good Governance, Accountability of Governmental Agencies and Development in Nigeria

Some scholars have argued that the enhanced performance of governmental agencies in any nation is a product of good governance, accountability, transparency and trust, which in turn brings about the improvement in the living standard of the people. The implication of this position is that where good governance is absent, accountability of governmental agencies and development in such a society is likely to be affected negatively. With the analysis of secondary data, the paper examines the challenges of good governance, accountability of governmental agencies and development in Nigeria. It observes the manifestation of unethical behaviour amongst public officials as the major challenge hindering development in the country. It therefore recommend among others the need for the government to strengthen the existing anti-corruption agencies to enable them enforce proper ethical standar

Odontogenic tumours: a review of 266 cases

Objectives: The aim of this study was to examine the relative frequency of odontogenic tumours at a tertiary hospital in Ibadan, as well as to study the various histologic types based on WHO 2005 classification and to compare results from this study with those of previous studies. Study design: The records of the Oral Pathology Department of University College Hospital were reviewed. Lesions diagnosed as odontogenic tumours were categorized into four groups based on WHO 2005 classification and were analyzed for age, sex and site using SPSS for Window (version 18.0; SPSS Inc. Chicago, IL) and frequency tables were generated. Results: Two hundred and sixty six (41.7%) cases of odontogenic tumours were seen. The mean age of occurrence was 32.6 (±15.815) years (range3-82 years) and peak age was in the third decade of life. Eleven (4.1%) malignant odontogenic tumours were seen. Ameloblastoma with 65.4% of cases was the most common odontogenic tumour followed by fibromyxoma (14.7%), no case of odontoma was seen in this series. Conclusion: The findings were mostly similar to those of African and Asian series and showed variations from reports from the Americas. The reason for the disparity in African and American series needs further investigations

Accountability for Sustainable Development and the Challenges of Leadership in Nigeria, 1999-2015

Development of any society is meant to enhance the living standard of citizens. However, where there are challenges of accountability, development is more likely to be a mirage. Past studies in Nigeria on the challenges of leadership and sustainable development identified corruption and lack of required skills on the part of public officials to perform in terms of proper policy formulation and implementation among others. The main goal of this article is to explore the relationship between accountability for the sustainable development and the challenges of leadership in Nigeria. With the analysis of data obtained from secondary sources, this present study identified lack of accountability for sustainable development to include the challenges leadership, unethical behavior, poor maintenance culture, poor management of resources, corruption on the part of public officials, and inadequate funds to execute projects in Nigeria. This article therefore recommends, among others, the need for government to adopt a more practical approach to the promotion of accountability, a determined fight against corruption and unethical behavior, proper management of resources, and devotion of more funds to the execution of capital projects that could positively affect the lives of the people for improved standard of living

Appraisal of jaw swellings in a Nigerian tertiary healthcare facility

Introduction: The mandible and maxilla can be the site of myriads of lesions that may be categorized as neoplastic, cystic, reactive and infective or inflammatory. Literature reviewing jaw swellings in an amalgamated fashion are uncommon, probably because aetiologies for these swellings are varied. However, to appreciate their relative relationship, it is essential to evaluate the clinico-pathologic profile of jaw swellings. The aim of this appraisal is to describe the array of jaw swellings seen at our hospital from 1990 to 2011, to serve as a reference database. Methodology: Biopsy records of all histologically diagnosed cases of jaw swellings seen at the department of Oral Pathology, University College Hospital between January 1990 and December 2011 were retrieved, coded and inputted into SPSS version 20. Data on prevalence, age, sex, site and histological diagnosis were analysed descriptively for each category of jaw swellings. All patients below 16 years were regarded as children. Results: A total of 638 jaw swellings were recorded in the 22-year study period. The Non Odontogenic Tumours (NOT) were the commonest, accounting for 46.2% of all jaw swellings. Odontogenic Tumours (OT) formed 45% of all adult jaw swelling while it formed 25.2% in children and adolescents. Ameloblastoma was the commonest while the most common NOT was ossifying fibroma (OF). Chronic osteomyelitis of the jaws was about 6 times commoner in adult females than males and mostly involved the mandible. The most common malignant jaw swelling was Burkitts' lymphoma (BL) that was about 7 times more in children than adults. Osteogenic sarcoma was the most common malignancy in adults. Conclusion: Jaw swellings are extensively varied in types and pattern of occurrence. This study has categorized jaw swellings in a simple but comprehensive fashion to allow for easy referencing in local and international data acquisition and epidemiological comparison

How well are Tropical Cyclones represented in reanalysis data sets?

Tropical cyclones (TCs) are identified and tracked in six recent reanalysis data sets and compared with those from the IBTrACS best track archive. Results indicate that nearly every cyclone present in IBTrACS over the period 1979-2012 can be found in all six reanalyses using a tracking and matching approach. However, TC intensities are significantly under-represented in the reanalyses compared to the observations. Applying a typical objective TC identification scheme, it is found that the largest uncertainties in TC identification occur for the weaker storms; this is exacerbated by uncertainties in the observations for weak storms and lack of consistency in operational procedures. For example, it is unclear whether certain types of storms, such as tropical depressions, subtropical cyclones and monsoon depressions, are included in the best track data for all reporting agencies. There are definite improvements in how well TCs are represented in more recent, higher resolution reanalyses; in particular MERRA2 is comparable with the NCEP-CFSR and JRA55 reanalyses, which perform significantly better than the older MERRA reanalysis

Solid-state, triboelectrostatic and dissolution characteristics of spray-dried piroxicam-glucosamine solid dispersions

This work explores the use of both spray drying and D-glucosamine HCl (GLU) as a hydrophilic carrier to improve the dissolution rate of piroxicam (PXM) whilst investigating the electrostatic charges associated with the spray drying process. Spray dried PXM:GLU solid dispersions were prepared and characterised (XRPD, DSC, SEM). Dissolution and triboelectric charging was also conducted. The results showed that the spray dried PXM alone, without GLU produced some PXM form II (DSC results) with no enhancement in solubility relative to that of the parent PXM. XRPD results also showed the spray drying process to decrease the crystallinity of GLU and solid dispersions produced. The presence of GLU improved the dissolution rate of PXM. Spray dried PXM: GLU at a ratio of 2:1 had the most improved dissolution. The spray drying process generally yielded PXM-GLU spherical particles of around 2.5 µm which may have contributed to the improved dissolution. PXM showed a higher tendency for charging in comparison to the carrier GLU (- 3.8 versus 0.5 nC/g for untreated material and -7.5 versus 3.1 nC/g for spray dried materials). Spray dried PXM and spray dried GLU demonstrated higher charge densities than untreated PXM and untreated GLU, respectively. Regardless of PXM:GLU ratio, all spray dried PXM:GLU solid dispersions showed a negligible charge density (net-CMR: 0.1 – 0.3 3nC/g). Spray drying of PXM:GLU solid dispersions can be used to produce formulation powders with practically no charge and thereby improving handling as well as dissolution behaviour of PXM