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91.
Milena Niemiec Maciej G?ogowski Dobromira Tyc-Szczepaniak Marek Wierzchowski Lucyna K?pka 《Reports of Practical Oncology and Radiotherapy》2011,16(2):49-53
Background and aim
Long-term survival of lung cancer patients with brain metastases (BM) is very rare. Our aim is to report the characteristics of patients who survived for at least three years after a BM diagnosis.Materials and methods
Nineteen lung cancer patients who had survived ≥3 years after a BM diagnosis were identified in our database. Seven (37%) had undergone whole-brain radiotherapy (WBRT) only, five (26%) BM surgery + WBRT, three (16%) BM surgery + WBRT + BM radiosurgery, and four (21%) no WBRT (one, surgery; one, radiosurgery; two, BM surgery + radiosurgery). Their characteristics were compared with historical data for 322 lung cancer patients with BM (control group, CG), who had received WBRT between 1986 and 1997.Results
Median survival from BM in long survivors group was 73 months (in CG – 4 months). Characteristics comparison: median age 55 vs. 58 (CG), p = 0.16; female sex 68% vs. 28% (CG), p = 0.003; RTOG/RPA class 1 – 75% vs. 13% (CG), p = 0.00001; adenocarcinoma histology 84% vs. 24% (CG), p < 0.00001; control of primary tumor 95% vs. 27% (CG), p < 0.00001; extracranial metastases 0 vs. 26% (CG), p = 0.01; single BM 63% vs. 9% (CG), p = 0.00001; surgery of BM 53% vs. 14% (CG), p = 0.00001.Conclusions
Beside prognostic factors already recognized as favorable in patients with BM, the adenocarcinoma histology and female sex were prevalent in long-term survivors of BM from lung cancer. 相似文献92.
93.
Chakravorty A Awad MM Hiscox TJ Cheung JK Carter GP Choo JM Lyras D Rood JI 《PloS one》2011,6(7):e22762
Clostridium perfringens is the causative agent of clostridial myonecrosis or gas gangrene and produces many different extracellular toxins and enzymes, including the cysteine protease α-clostripain. Mutation of the α-clostripain structural gene, ccp, alters the turnover of secreted extracellular proteins in C. perfringens, but the role of α-clostripain in disease pathogenesis is not known. We insertionally inactivated the ccp gene C. perfringens strain 13 using TargeTron technology, constructing a strain that was no longer proteolytic on skim milk agar. Quantitative protease assays confirmed the absence of extracellular protease activity, which was restored by complementation with the wild-type ccp gene. The role of α-clostripain in virulence was assessed by analysing the isogenic wild-type, mutant and complemented strains in a mouse myonecrosis model. The results showed that although α-clostripain was the major extracellular protease, mutation of the ccp gene did not alter either the progression or the development of disease. These results do not rule out the possibility that this extracellular enzyme may still have a role in the early stages of the disease process. 相似文献
94.
Soto-De Leon S Camargo M Sanchez R Munoz M Perez-Prados A Purroy A Patarroyo ME Patarroyo MA 《PloS one》2011,6(2):e14705
Background
Infection with multiple types of human papillomavirus (HPV) is one of the main risk factors associated with the development of cervical lesions. In this study, cervical samples collected from 1,810 women with diverse sociocultural backgrounds, who attended to their cervical screening program in different geographical regions of Colombia, were examined for the presence of cervical lesions and HPV by Papanicolau testing and DNA PCR detection, respectively.Principal Findings
The negative binomial distribution model used in this study showed differences between the observed and expected values within some risk factor categories analyzed. Particularly in the case of single infection and coinfection with more than 4 HPV types, observed frequencies were smaller than expected, while the number of women infected with 2 to 4 viral types were higher than expected. Data analysis according to a negative binomial regression showed an increase in the risk of acquiring more HPV types in women who were of indigenous ethnicity (+37.8%), while this risk decreased in women who had given birth more than 4 times (−31.1%), or were of mestizo (−24.6%) or black (−40.9%) ethnicity.Conclusions
According to a theoretical probability distribution, the observed number of women having either a single infection or more than 4 viral types was smaller than expected, while for those infected with 2–4 HPV types it was larger than expected. Taking into account that this study showed a higher HPV coinfection rate in the indigenous ethnicity, the role of underlying factors should be assessed in detail in future studies. 相似文献95.
96.
Gommet C Billecocq A Jouvion G Hasan M Zaverucha do Valle T Guillemot L Blanchet C van Rooijen N Montagutelli X Bouloy M Panthier JJ 《PLoS neglected tropical diseases》2011,5(12):e1421
Background
Rift Valley fever virus (RVFV) causes disease in livestock and humans. It can be transmitted by mosquitoes, inhalation or physical contact with the body fluids of infected animals. Severe clinical cases are characterized by acute hepatitis with hemorrhage, meningoencephalitis and/or retinitis. The dynamics of RVFV infection and the cell types infected in vivo are poorly understood.Methodology/Principal Findings
RVFV strains expressing humanized Renilla luciferase (hRLuc) or green fluorescent protein (GFP) were generated and inoculated to susceptible Ifnar1-deficient mice. We investigated the tissue tropism in these mice and the nature of the target cells in vivo using whole-organ imaging and flow cytometry. After intraperitoneal inoculation, hRLuc signal was observed primarily in the thymus, spleen and liver. Macrophages infiltrating various tissues, in particular the adipose tissue surrounding the pancreas also expressed the virus. The liver rapidly turned into the major luminescent organ and the mice succumbed to severe hepatitis. The brain remained weakly luminescent throughout infection. FACS analysis in RVFV-GFP-infected mice showed that the macrophages, dendritic cells and granulocytes were main target cells for RVFV. The crucial role of cells of the monocyte/macrophage/dendritic lineage during RVFV infection was confirmed by the slower viral dissemination, decrease in RVFV titers in blood, and prolonged survival of macrophage- and dendritic cell-depleted mice following treatment with clodronate liposomes. Upon dermal and nasal inoculations, the viral dissemination was primarily observed in the lymph node draining the injected ear and in the lungs respectively, with a significant increase in survival time.Conclusions/Significance
These findings reveal the high levels of phagocytic cells harboring RVFV during viral infection in Ifnar1-deficient mice. They demonstrate that bioluminescent and fluorescent viruses can shed new light into the pathogenesis of RVFV infection. 相似文献97.
Veljkovic M Dopsaj V Dopsaj M Branch DR Veljkovic N Sakarellos-Daitsiotis MM Veljkovic V Glisic S Colombatti A 《PloS one》2011,6(11):e28304
Background
There is convincing evidence from numerous clinical and epidemiological studies that physical activity can reduce the risk for breast and prostate cancer. The biological mechanisms underlying this phenomenon remain elusive. Herein we suggest a role for naturally produced antibodies reactive with the vasoactive intestinal peptide (VIP) in the suppression of breast and prostate cancer, which we believe could offer a possible molecular mechanism underlying control of these cancers by physical exercise.Methodology and Results
We found that sera from individuals having breast and prostate cancers have decreased titers of VIP natural antibodies as demonstrated by a lower reactivity against peptide NTM1, having similar informational and structural properties as VIP. In contrast, sera collected from elite athletes, exhibited titers of natural NTM1-reactive antibodies that are significantly increased, suggesting that physical activity boosts production of these antibodies.Significance
Presented results suggest that physical exercise stimulates production of natural anti-VIP antibodies and likely results in suppression of VIP. This, in turn, may play a protective role against breast and prostate cancers. Physical exercise should be further investigated as a potential tool in the treatment of these diseases. 相似文献98.
99.
A recent re-emerging bacterial canker disease incited by Pseudomonas syringae pv. actinidiae (Psa) is causing severe economic losses to Actinidia chinensis and A. deliciosa cultivations in southern Europe, New Zealand, Chile and South Korea. Little is known about the genetic features of this pathovar. We generated genome-wide Illumina sequence data from two Psa strains causing outbreaks of bacterial canker on the A. deliciosa cv. Hayward in Japan (J-Psa, type-strain of the pathovar) and in Italy (I-Psa) in 1984 and 1992, respectively as well as from a Psa strain (I2-Psa) isolated at the beginning of the recent epidemic on A. chinensis cv. Hort16A in Italy. All strains were isolated from typical leaf spot symptoms. The phylogenetic relationships revealed that Psa is more closely related to P. s. pv. theae than to P. avellanae within genomospecies 8. Comparative genomic analyses revealed both relevant intrapathovar variations and putative pathovar-specific genomic regions in Psa. The genomic sequences of J-Psa and I-Psa were very similar. Conversely, the I2-Psa genome encodes four additional effector protein genes, lacks a 50 kb plasmid and the phaseolotoxin gene cluster, argK-tox but has acquired a 160 kb plasmid and putative prophage sequences. Several lines of evidence from the analysis of the genome sequences support the hypothesis that this strain did not evolve from the Psa population that caused the epidemics in 1984-1992 in Japan and Italy but rather is the product of a recent independent evolution of the pathovar actinidiae for infecting Actinidia spp. All Psa strains share the genetic potential for copper resistance, antibiotic detoxification, high affinity iron acquisition and detoxification of nitric oxide of plant origin. Similar to other sequenced phytopathogenic pseudomonads associated with woody plant species, the Psa strains isolated from leaves also display a set of genes involved in the catabolism of plant-derived aromatic compounds. 相似文献
100.