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The RNA2 of seven grapevine fanleaf virus (GFLV) isolates from vines with yellow mosaic (YM) symptoms from different origin were sequenced. These sequences showed a high variability in the homing protein (2AHP) and, in five of them, a putative recombination with arabis mosaic virus (ArMV) was detected. To investigate recombination frequency, the partial sequences of the 2AHP of 28 additional GFLV isolates from nine different countries, showing either YM or infectious malformations (MF) symptoms, were obtained and compared with those of GFLV isolates from GenBank. The analysis confirmed the high level of sequence variability (up to 41 % at the nucleotide level) among isolates. In phylogenetic trees constructed using different approaches, the sequenced isolates always clustered in four conserved groups, three of which comprised YM strains (groups 1, 2 and 3), and one (group 4) the MF strains. Potential interspecific recombination sites between GFLV and ArMV were predicted in the 2AHP gene of several isolates, all of which were associated with YM symptoms.  相似文献   
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IntroductionBurnt sugarcane harvesting requires intense physical exertion in an environment of high temperature and exposure to particulate matter.ObjectiveTo evaluate the effects of burnt sugarcane harvesting on rhinitis symptoms and inflammatory markers in sugarcane workers.MethodsA total of 32 male sugarcane workers were evaluated with questionnaire for rhinitis symptoms, and for inflammatory markers on peripheral blood and nasal lavage, in the non-harvesting, and 3 and 6 months into the sugarcane harvesting period. Weather data and particulate matter fine concentrations were measured in the same day.ResultsThe particulate matter concentrations in sugarcane harvesting were 27 (23–33 μg/m3), 112 (96–122 μg/m3), and 63 (17–263 μg/m3); 24 h temperatures were 32.6 (25.4–37.4 °C), 32.3 (26.7–36.7 °C) and 29.7 (24.1–34.0 °C) and relative humidities were 45.4 (35.0–59.7%), 47.9 (39.1–63.0%), and 59.9 (34.7–63.2%) in the non-harvesting period, three and 6 months of the harvesting period. The age was 37.4 ± 10.9 years. The prevalence of rhinitis symptoms was significantly higher at 3 months of the harvesting period (53.4%), compared to non-harvesting period (26.7%; p = 0.039) and at 6 months into the harvesting period (20%; p = 0.006). Concentrations of interleukin 6 (IL-6) in nasal lavage increased after 3 months of the harvesting period compared to the non-harvesting period (p = 0.012). The presence of rhinitis symptoms, after 3 months of the harvesting period, was directly associated with blood eosinophils and inversely associated with neutrophils.ConclusionsAfter 3 months of work in burnt sugarcane harvesting the prevalence of rhinitis symptoms and IL-6 in nasal lavage increased. Furthermore, eosinophil counts were directly associated with the rhinitis symptoms in the period of higher concentration of particulate matter.  相似文献   
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Background::Tuberculosis (TB) prevention through the use of preventive treatment is a critical activity in the elimination of TB. In multiple settings, limited ...  相似文献   
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OBJECTIVE: To investigate frequency and associated factors of post polio syndrome (PPS) in an Italian cohort of people with prior poliomyelitis. METHODS: We screened subjects admitted for poliomyelitis at the paediatric hospital of the University of Palermo during the time frame 1945-1960. Patients who developed PPS were identified through a structured questionnaire and a neurologic examination. PPS diagnosis was made according to specified diagnostic criteria. Frequency of PPS was calculated in the selected cohort of polio survivors. The association with the investigated risk factors (sex, age at onset of polio, extension and severity of polio, education, associated diseases, cigarette smoking, trauma, polio vaccination) was analysed by the calculation of the odds ratio. RESULTS: Forty-eight participants met the adopted diagnostic criteria for PPS, giving a prevalence of 31.0%. The prevalence rate was significantly higher in women than in men (p=0.02). Logistic regression analyses revealed a significant inverse association with onset of poliomyelitis at over 12 months of age (OR 0.33; CI 0.14-0.79) a higher degree of education (OR 0.20; CI 0.07-0.79), and a significant association with the presence of other diseases (OR 9.86; CI 3.69-26.34). CONCLUSIONS: In our survey one-third of patients with prior poliomyelitis had PPS. Higher age at onset of poliomyelitis is inversely associated with PPS. The association with other diseases may indicate that a chronic physical stress, particularly in already weak motor units, can contribute to the development of signs and symptoms of PPS. Our results also suggest the impact of socio-economic conditions on the risk of PPS.  相似文献   
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Matrix metalloproteinases, in particular the gelatinases MMP-2 and MMP-9, have received great attention in recent years as putative tumour markers for clinical applications. The main reason for the observed interest is their easy detection in body fluids. Moreover, recent evidence has shown multiple functions of MMPs, rather than simply degrading ECM, which include the mobilisation of growth factors and processing of surface molecules. Several authors have reported increased levels of MMPs in a number of cancers, but clinical correlations in breast cancer are still fragmentary. Thus, the aim of the present research was to investigate the activity levels of circulating gelatinases in the sera of breast cancer patients by means of zymographic analysis, and correlate data with clinicopathological parameters. In all, 80 patients and 22 healthy volunteers were involved in this study. Sera were obtained prior to surgery. The clinical variables were: grading of tumours, tumour size, lymph node involvement, tumour staging, oestrogen and progesterone receptor levels (76 out of 80 cases), and c-erbB-2 levels (46 cases). The densitometric measures of MMP-2 and MMP-9 activity levels indicated that the average values of both gelatinase activities were significantly higher in breast cancers than in control sera (P<0.0001). In addition, our analysis showed for the first time that elevated activity levels of both gelatinases correlated only with c-erbB-2 overexpression (P=0.0273 for MMP-2 and P=0.0075 for MMP-9). An inverse correlation was observed with regard to oestrogen receptor expression (P=0.0075 for MMP-2 and P=0.0273 for MMP-9). Moreover, a borderline inverse correlation was observed between the activity levels of both enzymes and nuclear grade (P=0.0511 for MMP-2 and P=0.0794 for MMP-9). In conclusion, the present data suggest that serum measures of MMP's activity may have diagnostic value for discriminating subgroups of breast cancer patients and support the hypothesis that ERBB2 amplification and/or overexpression enhance signalling pathways that may lead to increased production of gelatinases in c-erbB-2 positive breast cancers with higher metastatic potentialities.  相似文献   
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In the present paper, we have examined whether human tissue inhibitor of metalloprotease1 (hTIMP1) is able to exert a growth factorlike effect on two clonal cell lines (BC3A and BC61), isolated from a parental line of human breast carcinoma cells (8701BC), and endowed with different growth and invasive behaviour in vitro and in nude mouse. The data obtained indicate that only the more tumorigenic clonal cell line (BC61) is responsive to hTIMP1 treatment by increasing its proliferative rate in a dosedependent manner. It was also found that BC61 cells selectively express a transmembrane protein of about 80kDa able to bind hTIMP1 in vitro and in vivo with high affinity (Kd of 0.07 ± 0.004 nM), and that treatment of BC61 cells with a proliferationpromoting concentration of hTIMP1 is able to stimulate tyrosinetargeted phosphorylation. The cumulative results obtained strongly support the hypothesis that hTIMP1, classically regarded as a collagenase inhibitor, may be a crucial element of the extracellular signalling network during breast cancer development by controlling cell growth phenotype in autocrine and paracrine manner, and that intratumoural heterogeneity for the biological response to TIMP1 may exist within the composite cell population of the primary tumour site.  相似文献   
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