4,442 research outputs found
Diversity of culturable moderately halophilic and halotolerant bacteria in a marsh and two salterns a protected ecosystem of Lower Loukkos (Morocco)
To study the biodiversity of halophilic bacteria in a protected wetland located in Loukkos (Northwest, Morocco), a total of 124 strains were recovered from sediment samples from a marsh and salterns. 120 isolates (98%) were found to be moderately halophilic bacteria; growing in salt ranges of 0.5 to 20%. Of 124 isolates, 102 were Gram-positive while 22 were Gram negative. All isolates were identified based on 16S rRNA gene phylogenetic analysis and characterized phenotypically and by screening for extracellular hydrolytic enzymes. The Gram-positive isolates were dominated by the genus Bacillus (89%) and the others were assigned to Jeotgalibacillus, Planococcus, Staphylococcus and Thalassobacillus. The Gram negative isolates were dominated by the genus Vibrio (41%) and the others were assigned to Halomonas, Psychrobacter, Marinobacterium, Pseudoalteromonas, Salinivibrio and Photobacterium. The growth of strains obtained under different physico-chemical conditions and the screening for hydrolytic enzymes showed a high diversity even within the same species
Chronic exposure to simulated space conditions predominantly affects cytoskeleton remodeling and oxidative stress response in mouse fetal fibroblasts
Microgravity and cosmic rays as found in space are difficult to recreate on earth. However, ground-based models exist to simulate space flight experiments. In the present study, an experimental model was utilized to monitor gene expression changes in fetal skin fibroblasts of murine origin. Cells were continuously subjected for 65 h to a low dose. (55 mSv) of ionizing radiation (IR), comprising a mixture of high-linear energy transfer (LET) neutrons and low-LET gamma-rays, and/or simulated microgravity using the random positioning machine (RPM), after which microarrays were performed. The data were analyzed both by gene set enrichment analysis (GSEA) and single gene analysis (SGA). Simulated microgravity affected fetal murine fibroblasts by inducing oxidative stress responsive genes. Three of these genes are targets of the nuclear factor-erythroid 2 p45-related factor 2 (Nrf2), which may play a role in the cell response to simulated microgravity. In addition, simulated gravity decreased the expression of genes involved in cytoskeleton remodeling, which may have been caused by the downregulation of the serum response factor (SRF), possibly through the Rho signaling pathway. Similarly, chronic exposure to low-dose IR caused the downregulation of genes involved in cytoskeleton remodeling, as well as in cell cycle regulation and DNA damage response pathways. Many of the genes or gene sets that were altered in the individual treatments (RPM or IR) were not altered in the combined treatment (RPM and IR), indicating a complex interaction between RPM and IR
Synthesis, Characterization and High In Vitro Antitumour Activity of Novel Triphenyltin Carboxylates
The synthesis and spectral characterization of six novel triphenyltin compounds are described. The
in vitro antitumour activity of three of these compounds against two human tumour cell lines, MCF-7,
a mammary tumour, and WiDr, a colon carcinoma, was determined. All three compounds are more
active than cis-platin, etoposide and doxorubicin against both tumour cell lines. They are as active
as mitomycin C against WiDr, but less active against MCF-7
Genetic characterization of wild-type measles viruses circulating in suburban Khartoum, 1997-2000
Measles remains endemic in many East African countries, where it is often associated with high morbidity and mortality. We collected clinical specimens from Sudanese measles patients between July 1997 and July 2000. Sequencing of the 3' 456 nucleotides of the nucleoprotein gene from 33 measles virus (MV) isolates and 8 RNA samples extracted from clinical specimens demonstrated the presence of a single endemic MV strain with little sequence variation over time (overall nucleotide divergence of 0 to 1.3%). This was confirmed by sequencing of the complete H gene of two isolates from 1997 and two from 2000, in which the overall divergence ranged between 0 and 0.5%. Comparison with MV reference strains demonstrated that the viruses belonged to clade B, genotype B3, and were most closely related to a set of viruses recently isolated in Nigeria. Our study demonstrates a remarkable genetic stability of an endemically circulating MV strain
Pedestrians with Disabilities and Town and City Streets: From Shared to Inclusive Space?
This article highlights the importance of ensuring that accessibility and inclusion for people with disabilities, as required by the UN Convention on the Rights of Persons with Disabilities, is fully embedded in efforts to reduce the dominance of cars in city streets and promote more active modes of travel (including walking, wheeling and cycling) in line with global agendas. Drawing on emerging findings from the Inclusive Public Space research project, we present and critically reflect on types of difficulty associated with streets in which what is commonly known as a ‘shared space’ design operates, and those in which all or part of the available space is designated as primarily for pedestrian use. The data on which this analysis is based is qualitative, deriving from 83 semi-structured interviews about the experiences of our participants (a substantial majority of whom identified as having a disability) in two large UK cities and their wider metropolitan areas. The types of exclusionary experience described by our participants are organised into two broad overlapping categories – first, difficulties associated with navigating environments in which kerbs have been removed; and second, difficulties associated with interacting with vehicles (including bicycles) within and at the boundaries of shared or pedestrian spaces. Our findings are in line with those of previous projects that challenge and complicate claims that ‘shared space’ design, with its removal of kerbs and controlled crossings, enhances safety and mobility for all. Further, they demonstrate that many of the concerns associated with ‘shared space’ environments are also applicable to other types of street environment intended primarily for pedestrians. As well as highlighting and raising awareness of potential types of exclusion against which action should be taken, we draw attention to measures that could reduce the risk of such exclusionary barriers arising and persisting
Genetic characterization of wild-type measles viruses circulating in suburban Khartoum, 1997-2000
Genetic characterization of wild-type measles viruses circulating in suburban Khartoum, 1997-2000
Serological and virological characterization of clinically diagnosed cases of measles in suburban Khartoum
Measles continues to be a major childhood disease in terms of global
morbidity and mortality. In the main areas of its endemicity the only
available means of diagnosis are based on clinical criteria: the presence
of a maculopapular rash and fever accompanied by cough, coryza, and/or
conjunctivitis. We have studied 38 clinically diagnosed cases of measles
in Khartoum, Sudan, by means of serology, reverse transcriptase PCR
(RT-PCR) on throat swabs and virus isolation from lymphocytes. On the
basis of serology, 28 patients were diagnosed as having an acute measles
virus (MV) infection, while in 10 cases the clinical symptoms proved to
have other causes. It was shown that in cases with low serum
immunoglobulin M (IgM) levels, an additional measurement of IgG or
virus-neutralizing antibodies was necessary to discriminate between
patients with an acute MV infection sampled during an early stage of the
disease and patients who had experienced an MV infection in the more
distant past. The serological laboratory diagnosis was validated by an
MV-specific RT-PCR: for all confirmed measles cases tested a fragment of
the correct size which hybridized with a third MV-specific primer could be
amplified, while all serologically negative cases were also RT-PCR
negative. MV could be isolated from 17 out of 23 of the serologically
confirmed cases, demonstrating that virus isolation is less reliable as a
diagnostic tool than serology or RT-PCR. This study stresses the urgent
need for a rapid diagnostic field test for measles
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