A Comparative Study of Adrenal Gland Development in Mouse and Chick Embryos

In this work, I describe in detail the development of cellular patterns in mouse and chick adrenals, in an attempt to discover the morphogenetic mechanisms that produce these patterns. Mouse adrenal gland tissues (chromaffin and cortical) are intermingled during embryonic life, but sort-out near the end of gestation into a central mass (medulla) of chromaffin tissue and a surrounding cortex. Once sorting out has occurred, the cells assemble into cortical zones and medullary cords. Chick adrenal gland tissues (chromaffin and cortical) are intermingled with each other during embryonic and post-hatching life. In mouse, the zona glomerulosa develops at day 1 and by day 4 both zona glomerulosa and fasciculata are obvious. By the end of the first week postnatal the cortex possesses three zones: zona glomerulosa, fasciculata and the developing X-zone. X-zone cells start to appear on the 4th day postnatal. The zona reticularis starts to develop while the X-zone is degenerating, about 32 days postnatal. An inner capsule is formed between the medulla and cortex of the male adrenal by 35 days postnatal (this process occurs later in females, during first pregnancy). Chromaffin cells start to be arranged in groups by 4 days postnatal and assume their final position in the centre of the gland (medulla) by 7 days postnatal. Different iation of chromaffin cells into A and NA cell types takes place in postnatal life. In chick, light and dark cortical cells are seen from 15 days of incubation up to and including 19 days. Zonation of cortical tissues is not seen. Differentiation of chromaffin cells into A and NA cell types takes place during post-hatching life. Sympathetic ganglion cells may contribute to the increased number of chromaffin cells by means of differentiation. At TEM level the cell surface of mouse adrenal tissues is smooth with little sign of elongated cellular processes, throughout the period when sorting out of the tissue types is occurring. Some elongated cells are seen during sorting out stages, but not later. The cell surfaces of chick adrenal cells were similar, but were not studied during stages when significant cell sorting was occurring. No obvious changes occur with respect to cell junctions (between like and unlike cells) in all stages studied in both mouse and chick adrenals. The distribution of fibronectin was analysed in embryonic mouse and chick by means of immunofluorescent labelling. Fibronectin was found in both mouse and chick embryonic adrenals at all stages studied, within the capsule, within blood vessels, around and between cortical cells, but only around groups of chromaffin cells, not within groups. There was no evidence for any quantitative variation in fibronectin that might have created an adhesive gradient to guide cell movement. An unexpected results of this work was the discovery of cell death in both cortical and chromaffin tissues in embryonic adrenals of mouse and chick. These findings have not been reported before. Morphometric analysis showed that mouse cortical tissue grows more rapidly than chromaffin during embryonic life and that mitosis is higher among corticals than chromaffins. It showed also that the medulla does not always form precisely in the centre of the gland. In a final discussion chapter, I consider the role of cell death in the embryonic adrenal, and suggest this may be to maintain a loose enough structure to allow active cell sorting. This chapter also discusses the possible mechanisms of cell sorting and concludes that the most likely process to be involved is differential adhesion. Suggestions are also made for further work on adrenal morphogenesis

Ocular Co-morbidity in Patients with Refractive Errors in Nigeria

Purpose: To d etermine the p attern and p revalence of other ocu lar p roblems seen in p atients with refractive errors in a Nigerian teaching hosp ital. Methods: A retrosp ective hosp ital-based review of all consecu tive p atients who p resented with signs and symp toms of refractive errors at the Obafemi Awolowo University Teaching Hosp itals Comp lex between 1st Janu ary 2007 and 31 Au gu st 2007. st Patients who had a d iagnosis of refractive error and su bsequ ently had d etailed eye examination were inclu d ed in this stu d y. Data was retrieved from the p atients’ clinical record s and analyzed with SPSS version 15. Results: Ou t of 724 new p atients seen within the stu d y p eriod , 235 had refractive errors (93 males and 142 females). Patients’ ages ranged between 7 and 74 years with a mean of 30.5+/ - 4.6 years. In more than half 54%) of the p atients, associated ocu lar co-morbid ities were d ocumented . The vision-imp airing d iseases d ocumented morbid ities in 56 (44.1) p atients were cataract 26 (20.5%), glau coma 20 (15.8%), d iabetic macu lop athy 3 (2.7%), amblyop ia, corneal op acities and CMV retinitis. Non vision-imp airing d isord ersd ocumented were conju nctivitis, 49 (38.6%); p terygium 6 (4.7%), chalazion 5 (3.9%), hypertensive retinop athy 4 (3.1%), d ry eyes and ep iscleritis. Immatu re cataract was responsible for abou t 2/ 3 of cases with p oor corrected visu al acu ity d ocumented in a large p rop ortion of the p atients 26 (11.1%). Conclusion: Patients with refractive errors need d etailed ocu lar examination for early d etection of other comorbid ities which may significantly affect vision and lead to avoid able blind ness and visu al imp airment.Key words: refractive errors, ocular co-morbid ity, glau coma, visu al imp airment, blind nes

Impact of gari consumption on the water resource of Nigeria

The consumption of gari (or roasted cassava granule) is connected to a chain of impacts on the water resource in the country where cassava crop is grown, processed and consumed. The aim of this paper is to assess the impact of gari consumption on the water resource of Nigeria. The paper elaborates on two types of impact: evaporation of infiltrated rainwater for cassava plant growth (green water use) and the abstraction of ground and/or surface water for processing, including that of consumption athousehold level (blue water use), while water pollution impacts during processing and consumption (at households) are neglected. Using the 2007 cassava production estimates for Nigeria as baseline, the water impact related to the consumption of gari either as snack or as “eba” (gari reconstituted with hot water to form a dough-like paste) is estimated at 10.52 x 109 m3, out of which 0.38% is due to the use of blue water and 91.3% is due to the use of green water (no dilution water impacts measured in this paper). Under the traditional farming practices, the major volume of water needed to grow the cassava plant is from rainwater. For the total water needed in gari consumption starting from cultivation, thewater used in the processing and consumption (at household level) is a significant fraction (about 0.4%) of the soil moisture used to grow the cassava plant. However, the impact of this fraction is often significant: One, it is the blue water (abstracted from surface and/or sub-surface sources) that is often scarcely available and two, it is this blue water sources that are also polluted by the waste flows from the processing and consumption sites

Brain Fag Syndrome – a myth or a reality

The Brain Fag Syndrome (BFS) is defined in the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) as a culture bound syndrome. BFS is a tetrad of somatic complaints; cognitive impairments; sleep related complaints; and other somatic impairments. Prince first described this psychiatric illness associated with study among African students in 1960. There have been questions relating to the nosological status of the syndrome as to whether: BFS is an objective or subjective phenomenon; it is one phenomenon or a variant of other known disorders; it is a mental illness ? These three questions pose challenges to the culture bound/depressive or anxiety equivalent approach to the condition. The scope of this paper is the scope of BFS history from its first reference in the psychological medicine to the most contemporary descriptions in transcultural psychiatry. The conceptual history of BFS is divided into four major perspectives: Traditional medicine, Psychoanalysis, Biopsychological and Transcultural psychiatry. This helps to outline some of the key issues, helps to clarify its nosological status, its present status and helps to set the stage for the future progress. From its conceptual history, BFS as a phenomenon, with its distinct presentations, is subjectively real and isbest classified with the framework of psychiatry, psychology and or sociology. The existence of BFS is evidenced by case as well as epidemiological reports of the condition in different locations. However, its course, response to treatment and outcome deserve more attention than has been given

Facteurs de contrôle de la diversité des plantations d’alignements dans la ville de Porto-Novo au Bénin

Les démarches de conservation et de maintien de la biodiversité en milieu urbain prennent en compte l’hétérogénéité spatiale et les pressions socio-anthropiques de la ville. Le suivi et l’optimisation des avantages des plantations urbaines commencent d’abord par une meilleure connaissance des caractéristiques du milieu qui influencent leur diversité. Ainsi, cette étude présente les facteurs de contrôle de la diversité des plantations d’alignement de la ville de Porto-Novo au Bénin. Un inventaire des espèces en plantation est associé aux paramètres structurant des axes routiers pour mettre en évidence l’importance des formes d’aménagement et de pression anthropique dans la modification du cortège floristique de la ville. Le test de Wilcoxon, la comparaison des paramètres de diversité ainsi que l’analyse canonique des correspondances (CCA) sont les principales méthodes utilisées pour le traitement des données à l’aide du logiciel R 3.0.3. Les résultats obtenus montrent que les paramètres de diversité varient entre niveaux d’urbanisation. Pendant que les besoins des populations exprimés à travers leur préférence en espèces contribuent à une augmentation sensible de près de 54% du cortège floristique de la ville, la largeur des rues et l’intensité des activités commerciales réduisent la densité linéaire et la diversité des plantations. L’intégration de ces constats dans la planification urbaine pourrait permettre un suivi écologique plus avantageux dans la ville.Mots-clés: diversité; plantations d’alignement, actions anthropiques, Porto-NovoDiversity control factors of alignment plantations in Porto-Novo town in Benin Biodiversity conservation and maintenance steps in urban environment take into account space heterogeneity and socio-anthropogenic pressures of the city. The follow-up and the optimization of urban plantations advantages start initially with a better knowledge of area characteristics which influence their diversity. Thus, this study presents diversity control factors of alignment plantations in Porto-Novo town in Bénin. An inventory of the species in plantation is associated to the road structuring parameters to show how planning form and the anthropogenic pressure can modify plant species composition the city. Wilcoxon tests, diversity parameters comparison as well as the first canonical correspondences analysis (CCA) are the principal methods used for data processing under the software R 3.0.3. Obtained results show that diversity parameters vary between urbanization levels. While people needs expressed through their specie preference contribute to increase floristic procession around 54%, the width of the streets and trading activities intensity reduce the linear density and the diversity patterns into plantations. The integration of these reports in the city planning could allow a more advantageous ecological follow-up in the city.Keywords: Diversity; Alignment plantations; anthropogenic actions; Porto-Novo

Global Charges in Chern-Simons theory and the 2+1 black hole

We use the Regge-Teitelboim method to treat surface integrals in gauge theories to find global charges in Chern-Simons theory. We derive the affine and Virasoro generators as global charges associated with symmetries of the boundary. The role of boundary conditions is clarified. We prove that for diffeomorphisms that do not preserve the boundary there is a classical contribution to the central charge in the Virasoro algebra. The example of anti-de Sitter 2+1 gravity is considered in detail.Comment: Revtex, no figures, 26 pages. Important changes introduced. One section added

Point-Coupling Models from Mesonic Hypermassive Limit and Mean-Field Approaches

In this work we show how nonlinear point-coupling models, described by a Lagrangian density that presents only terms up to fourth order in the fermion condensate $(\bar{\psi}\psi)$, are derived from a modified meson-exchange nonlinear Walecka model. The derivation can be done through two distinct methods, namely, the hypermassive meson limit within a functional integral approach, and the mean-field approximation in which equations of state at zero temperature of the nonlinear point-coupling models are directly obtained.Comment: 18 pages. Accepted for publication in Braz. J. Phy

Bacteriocinogenicity and production of pyocins from Pseudomonas species isolated in Lagos, Nigeria

A total of 52 strains of Pseudomonas identified as P. aeruginosa (27), P. putida (9), P. fluorescens (13) and P. stutzeri (3) were isolated from Nigerian patients with burns, wound and skin infections, UTI,diarrhoea and eye infections. 81.5, 55.6, 76.9 and 33.3% of these species produced pyocins at a range of 410 – 670 g/ml. High yields of pyocins at 35 – 37oC, which declined sharply at temperatures above37oC were obtained from all the producing strains. The strains also displayed significant pyocin expression (P 3 mm. These pyocins also displayed growth inhibitory activity against some Nigerian isolates of Gram-positive and Gram-negative bacteria when undiluted and at 1:2 - 1:16 dilutions. The susceptible organisms include Bacillus cereus, Listeria monocytogenes, Klebsiella spp., Staphylococcus aureus, S. epidermidis,Proteus spp. and Vibrio parahaemolyticus. The results of this study have provided evidence for broadspectrum antibacterial activity of pyocins elicited by Pseudomonas species from Nigeri

Multiplex cytokine analysis of dermal interstitial blister fluid defines local disease mechanisms in systemic sclerosis.

Clinical diversity in systemic sclerosis (SSc) reflects multifaceted pathogenesis and the effect of key growth factors or cytokines operating within a disease-specific microenvironment. Dermal interstitial fluid sampling offers the potential to examine local mechanisms and identify proteins expressed within lesional tissue. We used multiplex cytokine analysis to profile the inflammatory and immune activity in the lesions of SSc patients