The DNA replication apparatus in Plasmodium falciparum gametocytes

DNA synthesis in gametocytes takes place at two points; at the onset of gametocytogenesis where the nucleic acid content increases from lc to 1.8c prior to the formation of stage I gametocytes, and again 10 to 12 days later at the onset of gametogenesis when the mature male gametocyte (stage V) replicates its genome three times leading to the formation of eight haploid male gametes in less than 10 minutes. The aim of this study was to evaluate the status of the P. falciparum DNA replication apparatus during gametocytogenesis, most of which no significant DNA synthesis takes place, and gametogenesis in which a sudden burst of DNA replication takes place. The proteins studied in this project were DNA topoisomerase 1 and 11 (Topol and II), Replication factor C (Rfc) and Proliferating cell nuclear antigen (Pcna) of which P. falciparum homologous have been previously identified, isolated and characterised. Standard indirect immunofluorescence assays (IFA) carried out on unsynchronised in vitro cultivated P. falciparum (3D7A) using rabbit polyclonal antiserum raised against recombinant PfRfcl, PfRfc2, PfRfc3, PfPcna and PfTopoII showed that all five proteins are present throughout gametocytogenesis. All five proteins appear to be predominantly located within the nuclear region and at significantly higher levels in stage I and V gametocytes. However PfRfc2 levels appeared to be significantly higher only in stage I gametocytes and was distinctly absent from the nucleus of stage V gametocytes. Western blot analysis showed no significant changes in the levels of these proteins occurred during gametogenesis, with the exception of PfRfc2, which appear to increase immediately after activation and then gradually decrease as gametogenesis progressed.RT-PCR detected the presence of PfRFC2, PARFC3, PfPCNA, PfDNA POL5 and PiTOPO 1 transcripts in mature gametocytes before and after activation. However, PfRFCl and PfTOPO II transcripts were not detected in mature gametocytes either before or after activation. Similar results in protein and RNA analysis were obtained whether gametocytes were grown in AlbuMax or serum supplemented medium. In situ hybridisation using fluorescein-labelled PfRFCl, PfRFC2, PfDNA POL8, PfTOPO 1 and PfTOPO II gene fragments showed pockets of fluorescence on the peripheral regions of schizonts away from the nuclear region stained by DAPI. PfRFC3 and PfPCNA probes appeared to show fluorescence emanating from the nuclear region of schizonts. In conclusion, the localisation and unique expression pattern of PfRfc2 observed before and during gametogenesis, from that of the other DNA replication proteins and in particular, PfRfcl and PfRfc3, appears to imply a significant role for PfRfc2. Further studies need to be carried out in order to get to a better understanding of the role of PfRfc2 during gametogenesis

BUSINESS PROCESS RE-ENGINEERING: WORTHWHILE LESSONS FROM QUALITY OF WORKLIFE AND EMPLOYEE INVOLVEMENT

Business process reengineering is changing the way employees work, both collectively and individually. Reengineering is reunfying the tasks into coherent business processes with changes such as adding new tasks to each job, reducing functional specialization of jobs, moving decision making down to the lowest levels of the organization, installing multiple process paths, and organizing workers into teams. Reengineering means that jobs will be more fluid, more complex, and less predictable. Jobs change, roles change, job preparation changes, values change, and compensation and performance measures change (Hammer & Champy, 1993). This blurs the functional structures and concentrates on process driven organization in the hope of aiding effectiveness for breakthrough gains and dramatic performance. Yet many reengineering projects either fail or do not produce the desired results as the people issues are not addressed satisfactorily. This paper proposes a Bottom Line = Quality Of Worklife / Employee Involvement Model which argues that reengineering can learn from the Quality of Worklife and Employee Involvement paradigm in handling the emerging dissonances from the change initiative. Spea7ically, the paper assesses the Implied shift in mode of performance appraisal, the emerging roles of human resource development and the subsequent implications on training, compensation, and general employee satisfaction for the success of BPR

Analysis of Thermomechanical Properties of Selected Class of Recycled Thermoplastic Materials Based on Their Applications

Polypropylene and polystyrene are petroleum-based thermoplastics which are commonly used and disposed of in the environment after their service life, leading to environmental degradation. There is a need to recycle polypropylene and polystyrene, but the effect of recycling on thermo-mechanical properties is not well understood. This study aims to determine thermo-mechanical properties of the recycled polypropylene and recycled polystyrene and compare them with corresponding virgin polypropylene and newly produced polystyrene (general purpose polystyrene 1540 and high impact polystyrene 7240). The study was carried out by preparing bar-shaped samples of recycled polypropylene, recycled polystyrene, general purpose polystyrene 1540, and high impact polystyrene 7240 by compression molding using a hot press and thermally characterizing them to determine glass transition temperature and melting temperature using differential scanning calorimetry. The changes in Young’s modulus, tensile strength, hardness, and toughness due to recycling activities were determined at room temperature (24 °C), 40 °C, 60 °C, and 80 °C. The thermo-mechanical properties of recycled polystyrene (PS) were found to be comparable to those of high impact polystyrene (HIPS) 7240. The study revealed that the hardness and toughness for the recycled polymers were higher than those of corresponding virgin polymers. On the other hand, tensile strength and Young's modulus for the recycled polymers were lower than those of the virgin polymers. Understanding the thermo-mechanical properties of the recycled polymers will contribute to more industrial applications hence increase the rate of recycling, resulting in a reduction in environmental pollution

An Outbreak of Rift Valley Fever in Northeastern Kenya, 1997-98

In December 1997, 170 hemorrhagic fever-associated deaths were reported in Carissa District, Kenya. Laboratory testing identified evidence of acute Rift Valley fever virus (RVFV). Of the 171 persons enrolled in a cross-sectional study, 31(18%) were anti-RVFV immunoglobulin (Ig) M positive. An age-adjusted IgM antibody prevalence of 14% was estimated for the district. We estimate approximately 27,500 infections occurred in Garissa District, making this the largest recorded outbreak of RVFV in East Africa. In multivariate analysis, contact with sheep body fluids and sheltering livestock in one’s home were significantly associated with infection. Direct contact with animals, particularly contact with sheep body fluids, was the most important modifiable risk factor for RVFV infection. Public education during epizootics may reduce human illness and deaths associated with future outbreaks

Health financing reform in Kenya- assessing the social health insurance proposal

Kenya has had a history of health financing policy changes since its   independence in 1963. Recently, significant preparatory work was done on a new Social Health Insurance Law that, if accepted, would lead to universal health coverage in Kenya after a tr&nsition period. Questions of economic  feasibility and political acceptability continue to be discussed, with   stakeholders voicing concerns on design features of the new proposal   submitted to the  Kenyan parliament in 2004. For economic, social, political and organisational reasons a transition period will be  necessary, which is likely to last more than a decade. However, important objectives such as access to health care  and avoiding impoverishment due to direct health care payments should be recognised from the start so that  steady progress towards effective universal coverage can be planned and achieved

Adult population as potential reservoir of NTD infections in rural villages of Kwale district, Coastal Kenya: implications for preventive chemotherapy interventions policy

<p>Abstract</p> <p>Background</p> <p>Neglected tropical diseases (NTDs) are major public health problems in developing countries where they contribute to suffering of populations living in poor settings. As part of a research project started in September 2009 in Kwale district, Coast Region, Kenya, a baseline cross-sectional survey was conducted in 5 rural villages to provide information on the status of NTDs, including urinary schistosomiasis, soil-transmitted helminthiasis (STH), and lymphatic filariasis. This paper presents the results of a parasitological investigation among adults in the study villages.</p> <p>Methods</p> <p>A total of 599 adults in the 5 study villages were tested for NTD infections in urine, stool and blood. The presence of <it>Schistosoma haematobium </it>infection was determined by the urine filtration method. The presence of STH in stool was determined by Kato-Katz method while filarial antigenaemia was determined using immunochromatographic (ICT) test.</p> <p>Results</p> <p>The study revealed high prevalence of hookworm (41.7%) and schistosomiasis (18.2%) infections among adults in the study villages. Of the 599 individuals examined, 50.1% had one or more helminthic infections. There was low level of polyparasitism with helminthic NTDs in the study population with 9.5% and 1.7% of the participants having two and three infections, respectively.</p> <p>Conclusions</p> <p>In the current study, hookworm and schistosomiasis infections were identified as important infections among adults living in areas of high endemicity for these infections. Thus, if this section of the population is left untreated it may remain an important potential reservoir and a source of re-infection for school-age children treated in school deworming programmes. Therefore, there is a need to design novel strategies for preventive chemotherapy interventions that could allow inclusion of adults in an effort to reduce force of infection in high endemic communities.</p

The Textualities of the AutobiogrAfrical

In your mind’s eye, summon a map of the world—that famous text. There, there is Africa. The familiar, highly visible bulge of head to horn and curve, and the islands as you travel down to the continent’s southernmost point. It is likely that your imagination, like ours, has archived the inherited template of a Mercator projection, the powerful sixteenth-century cartography which remains influential offline and e-nfluential on Google Maps, even though it misleadingly distorts the size of continents. The 30.2 million square kilometers of the African continent appear much smaller than, say, the areas of the US (9.1 million square kilometers), Russia (16.4 million square kilometers), or China (9.4 million square kilometers). In comparison, the corrective cartographic morphing of the GallPeters projection revises the habituated representational geography of the world’s landmasses, showing the relational sizes of continents more accurately.1 Such tensions are not surprising, for the map, we know, is not to be equated with the territory and, in the context of our interest in this special issue in the textualities of the AutobiogrAfrical, divergent cartographies of the same space, drafted from different ideological perspectives, remind us to ask questions about how life narratives might make Africa intelligible. If, as Frances Stonor Saunders observes, “the self is an act of cartography, and every life a study of borders,” then “[e]nvisioning new acts of cartography that give substance and dynamism to the spaces between borders … produces new selves—or, at the very least, new ways of thinking about selfhood—and thus new objects of autobiographical enquiry.” 2 Any map of Africa reflects assumptions about a collective (“Africa”), as well as the political-geographical divisions of nation-states. “Africa” implies degrees of commonality among the (possibly more than) fifty-four countries that comprise the continent. Yet we know the dangers of a single story. Africa is not, after all, a country. Bear in mind, too, that our editorial team is located at the bottom end of the continent in South Afric