We have developed a simple precipitation route to synthesize magnetite (Fe
3O
4) nanoparticles with controlled size without any requirement of calcination step at high temperatures. The study of ...these nanoparticles indicates an enhancement in saturation magnetization with reduction in size down to ∼10 nm beyond which the magnetization reduces. The latter is attributed to surface effects becoming predominant as surface to core volume ratio increases. From the view-point of applications, 10 nm size of magnetite particles seems to be the optimum.
Nucleocytoplasmic transport is a broadly conserved process across eukaryotes. Despite its essential function and conserved mechanism, components of the nuclear transport apparatus have been ...implicated in genetic conflicts in Drosophila, especially in the male germ line. The best understood case is represented by a truncated RanGAP gene duplication that is part of the segregation distorter system in Drosophila melanogaster. Consistent with the hypothesis that the nuclear transport pathway is at the heart of mediating genetic conflicts, both nucleoporins and directionality imposing components of nuclear transport have previously been shown to evolve under positive selection. Here, we present a comprehensive phylogenomic analysis of importins (karyopherins) in Drosophila evolution. Importins are adaptor molecules that physically mediate the transport of cargo molecules and comprise the third component of the nuclear transport apparatus. We find that importins have been repeatedly gained and lost throughout various stages of Drosophila evolution, including two intriguing examples of an apparently coincident loss and gain of nonorthologous and noncanonical importin-α. Although there are a few signatures of episodic positive selection, genetic innovation in importin evolution is more evident in patterns of recurrent gene birth and loss specifically for function in Drosophila testes, which is consistent with their role in supporting host genomes defense against segregation distortion.
Here, we analyze stochastically a computer system by taking one more similar unit (called computer system) in cold standby redundancy. The computer system consists of hardware and software components ...together. The provision of a single service facility has been made for repairing hardware and up-grading the software. The failure of the service facility is considered which resumes the jobs with full efficiency as new after availing treatment. The failure rates of hardware and software components as well as failure rate of the service facility are taken as constant and thus follow negative exponential distribution. The treatment rate of the service facility, repair rate of the hardware and up-gradation rate of the software follow arbitrary distributions with different probability density functions. Efforts have been made to determine reliability measures in steady state by using SMP and RPT. The behavior of MTSF, availability and also the profit function is observed graphically for some particular situations of the parameters.
Two-year outcomes of MOBILITY Total Ankle Replacement Ramaskandhan, Jayasree R; Kakwani, Rajeshkumar; Kometa, Simon ...
Journal of bone and joint surgery. American volume,
2014-Apr-02, Letnik:
96, Številka:
7
Journal Article
Recenzirano
There is little literature on patient-reported outcomes following total ankle replacement in patients with osteoarthritis, posttraumatic osteoarthritis, and rheumatoid arthritis. We compared the ...differences in demographic data and clinical and patient-reported outcomes among patients with those types of arthritis who underwent total ankle replacement performed with use of the MOBILITY Total Ankle System.
Patients were divided into three groups based on the preoperative diagnosis of type of arthritis. We analyzed patient demographic data, American Orthopaedic Foot & Ankle Society (AOFAS) scores, and patient-reported outcomes as measured with use of the Foot and Ankle Outcome Score (FAOS), the 36-item Short-Form (SF-36) Health Survey, and patient-satisfaction scores, collected preoperatively and at one and two years postoperatively.
The study included 106 consecutive patients who underwent total ankle replacement between March 2006 and December 2009. The posttraumatic osteoarthritis group, which had twenty-eight patients, was significantly younger (mean age, 54.8 yrs; p < 0.05) than the other groups; the rheumatoid arthritis group, which had twenty-two patients, had a significantly lower mean body mass index (24.5 kg/m(2); p < 0.05); and the osteoarthritis group, which had fifty-six patients, had a higher proportion of males (41 males; p < 0.05). The posttraumatic osteoarthritis group reported better scores for two of the eight domains of the SF-36 preoperatively. At one year postoperatively, the posttraumatic osteoarthritis group and the rheumatoid arthritis group had better FAOS results regarding pain than those of the osteoarthritis group, and the posttraumatic osteoarthritis group also reported better scores for the general health domain of the SF-36. At two years, the posttraumatic group continued to show significantly higher scores for the general health domain of the SF-36. There was no significant difference between the groups in terms of the AOFAS scores, other FAOS results, or the patient-satisfaction scores at one and two years postoperatively.
Our findings suggest that early outcomes after total ankle replacement for patients with posttraumatic osteoarthritis are comparable with those for patients with osteoarthritis and rheumatoid arthritis.
Abstract Background We estimated vaccine effectiveness (VE) against pediatric influenza B hospitalizations in Hong Kong year round between November 2001 and October 2014. Methods We conducted a ...test-negative year-round study, enrolling children 6 months to 17 years of age admitted to two hospitals in Hong Kong with a febrile acute respiratory infection. Children were tested for influenza A and B. Conditional logistic regression was used to estimate overall and lineage-specific vaccine effectiveness comparing influenza vaccination history of the trivalent influenza vaccine (TIV) among patients testing positive for influenza B versus negative for influenza A and B, adjusting for age and sex and matching by calendar week of recruitment. Results Of the 6013 children included in the analysis, 262 tested positive for influenza B. Vaccination coverage was low: 6.5% in the influenza B positive children when compared with 8.8% in children who tested negative for both influenza A and B ( p = 0.248). Overall, VE was 47.6% (95% CI: 10.0, 69.4%) against influenza B hospitalization despite variable co-circulation of both lineages in all years. VE for Victoria-like virus calculated from 3 years when the vaccine was lineage-matched was 59.1% (95% CI: 6.2, 82.2%). Lineage-matched VE for Yamagata-like virus was -8.8% (95% CI: -215.4, 62.5%) in a clade mismatch season. With wide confidence intervals, we were unable to demonstrate cross-lineage protection: VE against the mismatched B/Yamagata-like virus was 9.5% (95% CI: -240.4, 76.0%) in 2011/12 and against mismatched B/Victoria-like virus in 2013/14 was 42.7% (95% CI: -368.6, 93.0%). Conclusions TIV conferred an overall VE of 47.6% (95% CI: 10.0, 69.4%) against influenza B hospitalization in children despite variable co-circulation of both lineages in all years. Lineage-matched VE for Yamagata-like virus was poor and may be related to clade mismatch. Cross-lineage protection was not observed.
Since the identification in early 2013 of severe disease caused by influenza A(H7N9) virus infection, there have been few attempts to characterize the full severity profile of human infections. Our ...objective was to estimate the number and severity of H7N9 infections in Guangzhou, using a serological study.
We collected residual sera from patients of all ages admitted to a hospital in the city of Guangzhou in southern China in 2013 and 2014. We screened the sera using a haemagglutination inhibition assay against a pseudovirus containing the H7 and N9 of A/Anhui/1/2013(H7N9), and samples with a screening titer ≥10 were further tested by standard hemagglutination-inhibition and virus neutralization assays for influenza A(H7N9). We used a statistical model to interpret the information on antibody titers in the residual sera, assuming that the residual sera provided a representative picture of A(H7N9) infections in the general population, accounting for potential cross-reactions.
We collected a total of 5360 residual sera from December 2013 to April 2014 and from October 2014 to December 2014, and found two specimens that tested positive for H7N9 antibody at haemagglutination inhibition titer ≥40 and a neutralization titer ≥40. Based on this, we estimated that 64,000 (95 % credibility interval: 7300, 190,000) human infections with influenza A(H7N9) virus occurred in Guangzhou in early 2014, with an infection-fatality risk of 3.6 deaths (95 % credibility interval: 0.47, 15) per 10,000 infections.
Our study suggested that the number of influenza A(H7N9) virus infections in Guangzhou substantially exceeded the number of laboratory-confirmed cases there, albeit with considerable imprecision. Our study was limited by the small number of positive specimens identified, and larger serologic studies would be valuable. Our analytic framework would be useful if larger serologic studies are done.
Severe acute respiratory syndrome (SARS) is a novel infectious disease with global impact. A virus from the family Coronaviridae has been identified as the cause, but the pathogenesis is still ...unclear.
Post-mortem tissue samples from six patients who died from SARS in February and March, 2003, and an open lung biopsy from one of these patients were studied by histology and virology. Only one full autopsy was done. Evidence of infection with the SARS-associated coronavirus (SARS-CoV) and human metapneumovirus was sought by reverse-transcriptase PCR and serology. Pathological samples were examined by light and electron microscopy and immunohistochemistry.
All six patients had serological evidence of recent infection with SARS-CoV. Diffuse alveolar damage was common but not universal. Morphological changes identified were bronchial epithelial denudation, loss of cilia, and squamous metaplasia. Secondary bacterial pneumonia was present in one case. A giant-cell infiltrate was seen in four patients, with a pronounced increase in macrophages in the alveoli and the interstitium of the lung. Haemophagocytosis was present in two patients. The alveolar pneumocytes also showed cytomegaly with granular amphophilic cytoplasm. The patient for whom full autopsy was done had atrophy of the white pulp of the spleen. Electron microscopy revealed viral particles in the cytoplasm of epithelial cells corresponding to coronavirus.
SARS is associated with epithelial-cell proliferation and an increase in macrophages in the lung. The presence of haemophagocytosis supports the contention that cytokine dysregulation may account, at least partly, for the severity of the clinical disease. The case definition of SARS should acknowledge the range of lung pathology associated with this disease.
Published online May 16, 2003 http://image.thelancet.com/extras/03art4347web.pdf
Highly pathogenic avian influenza (HPAI) H5N1 virus is entrenched in poultry in Asia and Africa and continues to infect humans zoonotically causing acute respiratory disease syndrome and death. There ...is evidence that the virus may sometimes spread beyond respiratory tract to cause disseminated infection. The primary target cell for HPAI H5N1 virus in human lung is the alveolar epithelial cell. Alveolar epithelium and its adjacent lung microvascular endothelium form host barriers to the initiation of infection and dissemination of influenza H5N1 infection in humans. These are polarized cells and the polarity of influenza virus entry and egress as well as the secretion of cytokines and chemokines from the virus infected cells are likely to be central to the pathogenesis of human H5N1 disease.
To study influenza A (H5N1) virus replication and host innate immune responses in polarized primary human alveolar epithelial cells and lung microvascular endothelial cells and its relevance to the pathogenesis of human H5N1 disease.
We use an in vitro model of polarized primary human alveolar epithelial cells and lung microvascular endothelial cells grown in transwell culture inserts to compare infection with influenza A subtype H1N1 and H5N1 viruses via the apical or basolateral surfaces.
We demonstrate that both influenza H1N1 and H5N1 viruses efficiently infect alveolar epithelial cells from both apical and basolateral surface of the epithelium but release of newly formed virus is mainly from the apical side of the epithelium. In contrast, influenza H5N1 virus, but not H1N1 virus, efficiently infected polarized microvascular endothelial cells from both apical and basolateral aspects. This provides a mechanistic explanation for how H5N1 virus may infect the lung from systemic circulation. Epidemiological evidence has implicated ingestion of virus-contaminated foods as the source of infection in some instances and our data suggests that viremia, secondary to, for example, gastro-intestinal infection, can potentially lead to infection of the lung. HPAI H5N1 virus was a more potent inducer of cytokines (e.g. IP-10, RANTES, IL-6) in comparison to H1N1 virus in alveolar epithelial cells, and these virus-induced chemokines were secreted onto both the apical and basolateral aspects of the polarized alveolar epithelium.
The predilection of viruses for different routes of entry and egress from the infected cell is important in understanding the pathogenesis of influenza H5N1 infection and may help unravel the pathogenesis of human H5N1 disease.
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