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1.
mtDNA diversity in rhesus monkeys reveals overestimates of divergence time and paraphyly with neighboring species 总被引:4,自引:0,他引:4
Reconstructions of the human-African great ape phylogeny by using
mitochondrial DNA (mtDNA) have been subject to considerable debate. One
confounding factor may be the lack of data on intraspecific variation. To
test this hypothesis, we examined the effect of intraspecific mtDNA
diversity on the phylogenetic reconstruction of another Plio- Pleistocene
radiation of higher primates, the fascicularis group of macaque (Macaca)
monkey species. Fifteen endonucleases were used to identify 10 haplotypes
of 40-47 restriction sites in M. mulatta, which were compared with similar
data for the other members of this species group. Interpopulational,
intraspecific mtDNA diversity was large (0.5%- 4.5%), and estimates of
divergence time and branching order incorporating this variation were
substantially different from those based on single representatives of each
species. We conclude that intraspecific mtDNA diversity is substantial in
at least some primate species. Consequently, without prior information on
the extent of genetic diversity within a particular species, intraspecific
variation must be assessed and accounted for when reconstructing primate
phylogenies. Further, we question the reliability of hominoid mtDNA
phylogenies, based as they are on one or a few representatives of each
species, in an already depauperate superfamily of primates.
相似文献
2.
D Y Mason J L Cordell A G Tse J J van Dongen C J van Noesel K Micklem K A Pulford F Valensi W M Comans-Bitter J Borst 《Journal of immunology (Baltimore, Md. : 1950)》1991,147(11):2474-2482
Recent evidence indicates that the transmembrane form of IgM on murine and human B lymphocytes is physically associated with at least two proteins, forming a disulfide-linked dimer, which may control cell surface expression of IgM and also play a role in signal transduction after Ag binding (by analogy with the TCR-associated CD3 components in T lymphocytes). We have used mAb and polyclonal antibodies against an intracytoplasmic epitope on one of these polypeptides (previously identified in murine B cells as the product of the B cell specific mb-1 gene) to study the distribution of the IgM-associated dimer in human cells. By immunocytochemical staining of normal and neoplastic B cells, we show that the human mb-1 protein appears early in B cell differentiation, probably before expression of cytoplasmic mu-chain, and persists until the plasma cell stage, where it is seen as an intracytoplasmic component. According to immunohistologic analysis of reactive lymphoid tissue and lymphoma samples, mb-1 protein is completely B cell specific. Anti-mb-1 also labels B cell areas in tissues from seven different mammalian species. Finally, the Ig-associated dimer could be isolated from human hairy-cell leukemia cells in high purity and yield by affinity chromatography using anti-mb-1 antibody. Mice immunized with this material have produced a strong polyclonal response, so that it should now be possible to prepare a panel of new mAb reactive with different epitopes on both mb-1 and on its associated polypeptide(s). 相似文献
3.
Sayem Ahmed Guibehi B. Koudou Maïwenn Bagot Franois Drabo Windtar R. Bougma Caisey Pulford Moses Bockarie Robert A. Harrison 《PLoS neglected tropical diseases》2021,15(6)
BackgroundSnakebite has become better recognized as a significant cause of death and disability in Sub-Saharan Africa, but the health economic consequences to victims and health infrastructures serving them remain poorly understood. This information gap is important as it provides an evidence-base guiding national and international health policy decision making on the most cost-effective interventions to better manage snakebite. Here, we assessed hospital-based data to estimate the health economic burden of snakebite in three regions of Burkina Faso (Centre-Ouest, Hauts Bassins and Sud-Ouest).MethodologyPrimary data of snakebite victims admitted to regional and district health facilities (eg, number of admissions, mortality, hospital bed days occupied) was collected in three regions over 17 months in 2013/14. The health burden of snakebite was assessed using Disability-Adjusted Life Years (DALYs) calculations based upon hospitalisation, mortality and disability data from admitted patients amongst other inputs from secondary sources (eg, populations, life-expectancy and age-weighting constants). An activity-based costing approach to determine the direct cost of snake envenoming included unit costs of clinical staff wages, antivenom, supportive care and equipment extracted from context-relevant literature.FindingsThe 10,165 snakebite victims admitted to hospital occupied 28,164 hospital bed days over 17 months. The annual rate of hospitalisation and mortality of admitted snakebite victims was 173 and 1.39/100,000 population, respectively. The estimated annual (i) DALYs lost was 2,153 (0.52/1,000) and (ii) cost to hospitals was USD 506,413 (USD 49/hospitalisation) in these three regions of Burkina Faso. These costs appeared to be influenced by the number of patients receiving antivenom (10.90% in total) in each area (highest in Sud-Ouest) and the type of health facility.ConclusionThe economic burden of snake envenoming is primarily shouldered by the rural health centres closest to snakebite victims–facilities that are typically least well equipped or resourced to manage this burden. Our study highlights the need for more research in other regions/countries to demonstrate the burden of snakebite and the socioeconomic benefits of its management. This evidence can guide the most cost-effective intervention from government and development partners to meet the snakebite-management needs of rural communities and their health centres. 相似文献
4.
Haralambieva E Jones M Roncador GM Cerroni L Lamant L Ott G Rosenwald A Sherman C Thorner P Kusec R Wood KM Campo E Falini B Ramsay A Marafioti T Stein H Kluin PM Pulford K Mason DY 《The Histochemical journal》2002,34(11-12):545-552
In a previous study, we showed that the high level of protein tyrosine phosphorylation present in lymphomas containing an anaplastic lymphoma kinase (ALK) can be demonstrated in routinely processed paraffin tissue sections using immunolabelling techniques. In the present study we investigated whether oncogenic tyrosine kinase activation also occurs in other categories of lymphoma by staining 145 cases of lymphoma covering those tumours with a range of different subtypes including those with morphological similarity to ALK-positive anaplastic large cell lymphoma (ALCL). Twelve cases of the borderline malignant disorder lymphomatoid papulosis were also studied. Twenty seven of the 28 cases of ALK-positive ALCL showed the extensive cytoplasmic labelling for phosphotyrosine in the neoplastic cells. The remaining case containing moesin-ALK exhibited membrane-associated phosphotyrosine expression. There was no nuclear phosphotyrosine labelling in any of the ALK-positive ALCL, even though ALK was present within the cell nuclei in 23 of the tumours. Variable degrees of phosphotyrosine labelling, usually membrane-restricted, were observed in 7/40 cases of ALK-negative ALCL, 9/29 cases of diffuse large B-cell lymphoma, 3/6 cases of mediastinal B-cell lymphoma, 2/7 cases of Hodgkin's lymphoma, 3/6 cases of peripheral T-cell lymphomas unspecified, 4/6 cases of B-cell chronic lymphocytic leukaemia, 2/6 cases of follicular lymphomas and 2/12 cases of lymphomatoid papulosis studied. However none of these phosphotyrosine-positive cases showed the strong cytoplasmic labelling comparable to that seen in ALK-positive lymphoma. We conclude that activation of a tyrosine kinase is probably not a major oncogenic event in lymphomas other than ALK-positive ALCL. 相似文献
5.
A nutrient thin film hydroponic system has been developed which allows rapid screening of willow (Salix) clones for their resistance to heavy metals, and hence their use in phytoremediation. Two clones known to be different in their resistance to heavy metals (Salix burjatica (Germany) and S. triandra x viminalis (Q83)), could be distinguished on the basis of leaf biomass, root biomass and stem height after 6 weeks. There were also differences in the uptake of heavy metals between the two clones. 相似文献
6.
Muma JB Lund A Siamudaala VM Munang'andu HM Munyeme M Matope G Nielsen K DJønne B Godfroid J Tryland M Skjerve E 《Journal of wildlife diseases》2010,46(4):1063-1069
One of the diseases of veterinary and public health importance affecting the Kafue lechwe (Kobus leche kafuensis) on the Kafue flats is brucellosis, for which only scant information is available. During the 2003 (October), 2004 (December), and 2008 (July-December) hunting seasons in the Kafue flats, we conducted a study to determine the seroprevalence of Brucella spp. in the Kafue lechwe and to evaluate serologic tests for detection of Brucella spp. antibodies in lechwe. The Rose Bengal Test (RBT), competitive enzyme-linked immunosorbent assay (cELISA), and fluorescence polarization assay (FPA) were used. A total of 121 Kafue lechwe were hunted for disease investigations in 2003, 2004, and 2008 in the Kafue Flat Game Management Area. Of these, 21.6%, (95% confidence interval [CI]: 14.2-29.1%) had detectable antibodies to Brucella spp. The Kafue lechwe in Lochnivar National Park had higher antibody results than those in Blue Lagoon National Park (odds ratio=3.0; 95% CI: 0.94-9.4). Infection levels were similar in females (21.6%) and males (21.7%). Results were similar among RBT, FPA, cELISA tests, suggesting that these could effectively be used in diagnosing brucellosis in the Kafue lechwe. Our study demonstrates the presence of Brucella infections in the Kafue lechwe in two national parks located in the Kafue flats and further highlights the suitability of serologic assays for testing the Kafue lechwe. Because the Kafue lechwe is the most hunted wildlife species in Zambia, hunters need to be informed of the public health risk of Brucella spp. infection. 相似文献
7.
8.
Susan DJ Chapple Anna M Crofts S Paul Shadbolt John McCafferty Michael R Dyson 《BMC biotechnology》2006,6(1):49-15
Background
A variety of approaches to understanding protein structure and function require production of recombinant protein. Mammalian based expression systems have advantages over bacterial systems for certain classes of protein but can be slower and more laborious. Thus the availability of a simple system for production and rapid screening of constructs or conditions for mammalian expression would be of great benefit. To this end we have coupled an efficient recombinant protein production system based on transient transfection in HEK-293 EBNA1 (HEK-293E) suspension cells with a dot blot method allowing pre-screening of proteins expressed in cells in a high throughput manner. 相似文献9.
Study design
A prospective treatment study with a new brace was conducted Objective. To evaluate radiological and subjective clinical results after one year conservative brace treatment with pressure onto lordosis at the thoracolumbar joint in children with scoliosis and kyphosis.Summary of background data
Conservative brace treatment of adolescent scoliosis is not proven to be effective in terms of lasting correction. Conservative treatment in kyphotic deformities may lead to satisfactory correction. None of the brace or casting techniques is based on sagittal forces only applied at the thoracolumbar spine (TLI= thoracolumbar lordotic intervention). Previously we showed in patients with scoliosis after forced lordosis at the thoracolumbar spine a radiological instantaneous reduction in both coronal curves of double major scoliosis.Methods
A consecutive series of 91 children with adolescent scoliosis and kyphosis were treated with a modified symmetric 30 degrees Boston brace to ensure only forced lordosis at the thoracolumbar spine. Scoliosis was defined with a Cobb angle of at least one of the curves [greater than or equal to] 25 degrees and kyphosis with or without a curve <25 degrees in the coronal plane. Standing radiographs were made i) at start, ii) in brace at beginning and iii) after one year treatment without brace.Results
Before treatment start ??in brace?? radiographs showed a strong reduction of the Cobb angles in different curves in kyphosis and scoliosis groups (sagittal n = 5 all p < 0.001, pelvic obliquity p < 0.001). After one year of brace treatment in scoliosis and kyphosis group the measurements on radiographs made without brace revealed an improvement in 3 Cobb angles each.Conclusion
Conservative treatment using thoracolumbar lordotic intervention in scoliotic and kyphotic deformities in adolescence demonstrates a marked improvement after one year also in clinical and postural criteria. An effect not obtained with current brace techniques. 相似文献10.
Role of the nucleophosmin (NPM) portion of the non-Hodgkin's lymphoma-associated NPM-anaplastic lymphoma kinase fusion protein in oncogenesis. 总被引:24,自引:2,他引:22
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The NPM-ALK fusion gene, formed by the t(2;5)(p23;q35) translocation in non-Hodgkin's lymphoma, encodes a 75-kDa hybrid protein that contains the amino-terminal 117 amino acid residues of the nucleolar phosphoprotein nucleophosmin (NPM) joined to the entire cytoplasmic portion of the receptor tyrosine kinase ALK (anaplastic lymphoma kinase). Here, we demonstrate the transforming ability of NPM-ALK and show that oncogenesis by the chimeric protein requires the activation of its kinase function as a result of oligomerization mediated by the NPM segment. Sedimentation gradient experiments revealed that NPM-ALK forms in vivo multimeric complexes of approximately 200 kDa or greater that also contain normal NPM. Cell fractionation studies of the t(2;5) translocation-containing lymphoma cell line SUP-M2 showed NPM-ALK to be localized within both the cytoplasmic and nuclear compartments. Immunostaining performed with both polyclonal and monoclonal anti-ALK antibodies confirmed the dual location of the oncoprotein and also indicated that NPM-ALK is abundant within both the nucleoplasm and the nucleolus. An intact NPM segment is absolutely required for NPM-ALK-mediated oncogenesis, as indicated by our observation that three different NPM-ALK mutant proteins lacking nonoverlapping portions of the NPM segment were each unable to form complexes, lacked kinase activity in vivo, and failed to transform cells. However, NPM could be functionally replaced in the fusion protein with the portion of the unrelated translocated promoter region (TPR) protein that activates the TPR-MET fusion kinase by mediating dimerization through its leucine zipper motif. This engineered TPR-ALK hybrid protein, which transformed cells almost as efficiently as NPM-ALK, was localized solely within the cytoplasm of cells. These data indicate that the nuclear and nucleolar localization of NPM-ALK, which probably occur because of transport via the shuttling activity of NPM, is not required for oncogenesis. Further, the activation of the truncated ALK protein by a completely heterologous oligomerization domain suggests that the functionally important role of the NPM segment of NPM-ALK in transformation is restricted to the formation of kinase-active oligomers and does not involve the alteration of normal NPM functions. 相似文献