A review of the literature on childhood Burkitt lymphoma in Nigeria

Background: Burkitt Lymphoma is common childhood tumour in sub Saharan Africa but the lack of centralized database on childhood cancer in Nigeria has made it difficult having a nationwide picture of its occurrence in the country.Objectives: This study was aimed at pooling published data from across the country with the hope of providing an overview of the profile of the disease in Nigeria.Methods: literature search was carried out on Pub Med/MEDLINE and Cochrane databases for all articles published between January 1975 and July 2015 using search strings such as children, cancer, Burkitt’s, epidemiology, prevalence, treatment and Nigeria. Based on specific criteria, 39 studies were included.Results: Burkitt Lymphoma was the most common childhood malignancy in most parts of the country accounting for 18.3- 65.0% of malignant tumours but a few centers observed Retinoblas-toma as the most common. There was a decline in the frequency of Burkitt lymphoma in Ibadan from 1960-2010 and in Lagos. Peak ages of occurrence ranged from 5- 10 years, more males and children from low socio-economic classes were affected. Different centers reported predominant involvement of either the jaw or the abdomen but there were slightly more centers with predominance of the jaw. Retrospective studies yielded an estimated survival of 15-23% while the Event Free Survival probabilities at two years was 43% and 48% for the Nigerian centers that participated in an international study.Conclusion: Burkitt Lymphoma is a common tumour in Nigeria. Establishment of Cancer registries for better data capture and funding for better treatment outcomes is recommended.Keywords: Burkitt Lymphoma; Nigeria; childhood; tumours; cance

Cascade atom in high-Q cavity: The spectrum for non-Markovian decay

The spontaneous emission spectrum for a three level cascade configuration atom in a single mode high-Q cavity coupled to a zero temperature reservoir of continuum external modes is determined from the atom-cavity mode master equation using the quantum regression theorem. Initially the atom is in its upper state and the cavity mode empty of photons. Following Glauber, the spectrum is defined via the response of a detector atom. Spectra are calculated for the detector located inside the cavity (case A), outside the cavity end mirror (Case B-end emission), or placed for emission out the side of the cavity (Case C). The spectra for case A and case B are found to be essentially the same. In all the cases the predicted lineshapes are free of instrumental effects and only due to cavity decay. Spectra are presented for intermediate and strong coupling regime situations (where both atomic transitions are resonant with the cavity frequency), for cases of non-zero cavity detuning, and for cases where the two atomic transition frequencies differ. The spectral features for Cases B(A) and C are qualitatively similar, with six spectral peaks for resonance cases and eight for detuned cases. These general features of the spectra can be understood via the dressed atom model. However, Case B and C spectra differ in detail, with the latter exhibiting a deep spectral hole at the cavity frequency due to quantum interference effects.Comment: 29 pages, 14 figures; v2: very minor correction to two equations, thicker lines in some figure

Relationship of socio-economic status and childhood cancer: an in-hospital cross-sectional study in a developing country

Background: Socioeconomic factors are known to affect health quality, disease occurrence as well as health-seeking behaviors in several ways.Objectives: To determine the influence of socio-economic factors on awareness of cancer, healthseeking behaviors among parents of children with cancer in a developing country and occurrence of cancer using Burkitt lymphoma as index malignancy.Methods: This was a descriptive cross-sectional study that involved children with cancer seen over a 2-year period in a tertiary hospital in Nigeria. Information was obtained by interview through administration of a questionnaire and retrieval of clinical data from patients’ case notes.Results: The caregivers of 91 children (46 boys, 45 girls) were interviewed including 86 biological parents. Majority (84.6%) of the children belonged to the low socio -economic classes 3-5; 45 of 86 parents (52.3%), more likely in parents from higher socioeconomic classes, were aware of cancer but only 7 (8.1%) knew it could occur in children. There was no association between Burkitt lymphoma and socio-economic class. Twenty-eight (30.8%) parents of the 91 children visited alternate sources of health care, most commonly traditional healers, followed by religious centers. There was no association between visits to such centers and the parents’ socio-economic status or with presentation with metastatic disease.Conclusions: Awareness of childhood cancer is low among this cohort of parents; their socioeconomic status seems to impact on this level of awareness but not on their health-seeking behaviors for their affected children. Focused health education is needed to increase childhood cancer awareness and appropriate healthseeking behavior among the population studied.Key words: socio-economic; childhood; cancer; health-seeking; behaviour; awarenes

A numerical investigation of the solution of a class of fourth-order eigenvalue problems

This paper is concerned with the accurate numerical approximation of the spectral properties of the biharmonic operator on various domains in two dimensions. A number of analytic results concerning the eigenfunctions of this operator are summarized and their implications for numerical approximation are discussed. In particular, the asymptotic behaviour of the first eigenfunction is studied since it is known that this has an unbounded number of oscillations when approaching certain types of corners on domain boundaries. Recent computational results of Bjorstad & Tjostheim, using a highly accurate spectral Legendre-Galerkin method, have demonstrated that a number of these sign changes may be accurately computed on a square domain provided sufficient care is taken with the numerical method. We demonstrate that similar accuracy is also achieved using an unstructured finite-element solver which may be applied to problems on domains with arbitrary geometries. A number of results obtained from this mixed finite-element approach are then presented for a variety of domains. These include a family of circular sector regions, for which the oscillatory behaviour is studied as a function of the internal angle, and another family of (symmetric and non-convex) domains, for which the parity of the least eigenfunction is investigated. The paper not only verifies existing asymptotic theory, but also allows us to make a new conjecture concerning the eigenfunctions of the biharmonic operator

Inbuilt Mechanisms for Overcoming Functional Problems Inherent in Hepatic Microlobular Structure

This paper is funded by an MRC/EPSRC Discipline Bridging Initiative Grant (G0502256-77947) to W. Wan

Plasma-Induced Heating Effects on Platinum Nanoparticle Size during Sputter Deposition Synthesis in Polymer and Ionic Liquid Substrates

Nanoparticle catalyst materials are becoming ever more important in a sustainable future. Specifically, platinum (Pt) nanoparticles have relevance in catalysis, in particular, fuel cell technologies. Sputter deposition into liquid substrates has been shown to produce nanoparticles without the presence of air and other contaminants and the need for precursors. Here, we produce Pt nanoparticles in three imidazolium-based ionic liquids and PEG 600. All Pt nanoparticles are crystalline and around 2 nm in diameter. We show that while temperature has an effect on particle size for Pt, it is not as great as for other materials. Sputtering power, time, and postheat treatment all show slight influence on the particle size, indicating the importance of temperature during sputtering. The temperature of the liquid substrate is measured and reaches over 150 \ub0C during deposition which is found to increase the particle size by less than 20%, which is small compared to the effect of temperature on Au nanoparticles presented in the literature. High temperatures during Pt sputtering are beneficial for increasing Pt nanoparticle size beyond 2 nm. Better temperature control would allow for more control over the particle size in the future

Neurological sequelae in survivors of cerebral malaria

Introduction: Cerebral malaria is a common cause of neurological sequelae and death in childhood. Information on persistent neurological sequelae post hospital discharge and their predisposing factors are scarce. Methods: This is a prospective study describing persisting neurological impairments post discharge among children treated for cerebral malaria. In addition the study was designed to investigate the frequency of persistent neurologic deficits and the risk factors for their persistence in these patients. The case records of 160 patients treated for CM at the Paediatrics Department of University College Hospital, Ibadan from January 2004 to November 2006 were reviewed to recruit cases. Recruited survivors were then followed up for information concerning the presence and persistence of neurological sequelae. Results: A total of 160 children aged 9 months to 134 months were admitted and treated for CM during the study period. One hundred and thirty one (81.9%) survived while 29 (18.1%) died. The 131 survivors of cerebral malaria consisted of 64 boys and 67 girls. Neurological sequelae occurred in 13.7% of survivors of cerebral malaria at discharge and 4.6% at follow up. Six children with neurological deficits at discharge had persistence of deficits 6 months post-hospital discharge and one at 24 months. No associations were found between hypoglycemia, anemia, age, sex and multiplicity of convulsions, and persistence of neurologic sequelae. The persisting neurologic deficits among survivors at follow up were: memory impairment (1.5%), seizure disorders (0.8%), visual impairment (0.8%), speech impairment (0.8%), monoparesis (0.8%) and hyperactivity (0.8%) at follow up. The longest persisting sequelae lasted for at least 24 months. Conclusion: Neurologic deficits are not uncommon complications of CM. Neurologic sequelae may persist for as long as 24 months or more in survivors of childhood CM. There is no association between the risk factors for neurologic deficits and persistent neurologic sequelae.Key words: Cerebral malaria, neurological sequelae, children, Nigeri

HIV infection in orphanages in South Western Nigeria

Background: As a result of the expanding HIV epidemic, affected children may end up in institutionalized care. Objectives: To determine the prevalence of HIV infection among children into orphanages in South Western Nigeria . Admission policies, knowledge and attitude of caregivers with respect to HIVwere also assessed Design: This was a cross sectional study in which interviewer administered questionnaires were used to collect information on consecutive children, heads of the orphanages and caregivers. Rapid HIV antibody testing was carried out. Results: A total of 190 children were enrolled from 7 homes with males accounting for 89 (46.8%). The main reasons for admission into the orphanages were; orphaned 85 (44.7%), abandoned 79 (41.6%) and mental illness in mother 11(5.8%). Two children were HIV positive, giving a prevalence rate of 1.05%. All the homes (100%) had a policy which excluded admission of HIV positive children but seldom carried out HIV testing at entry. Fear of disease transmission to others was the reason given for not admitting such children. Conclusion: The policy which excluded admission of HIV infected children may have contributed to the low prevalence of the infection in the orphanages. There needs to be a reform on the current policies in order to reduce discr iminat ion against HIV orphans.Keywords: HIV; Prevalence; Children; Orphanages; Admission policies; Caregiver