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51.
This review identified fourteen reported illness outbreaks attributed to consumption of pathogen-contaminated spice during the period 1973–2010. Countries reporting outbreaks included Canada, Denmark, England and Wales, France, Germany, New Zealand, Norway, Serbia, and the United States. Together, these outbreaks resulted in 1946 reported human illnesses, 128 hospitalizations and two deaths. Infants/children were the primary population segments impacted by 36% (5/14) of spice-attributed outbreaks. Four outbreaks were associated with multiple organisms. Salmonella enterica subspecies enterica was identified as the causative agent in 71% (10/14) of outbreaks, accounting for 87% of reported illnesses. Bacillus spp. was identified as the causative agent in 29% (4/10) of outbreaks, accounting for 13% of illnesses. 71% (10/14) of outbreaks were associated with spices classified as fruits or seeds of the source plant. Consumption of ready-to-eat foods prepared with spices applied after the final food manufacturing pathogen reduction step accounted for 70% of illnesses. Pathogen growth in spiced food is suspected to have played a role in some outbreaks, but it was not likely a contributing factor in three of the larger Salmonella outbreaks, which involved low-moisture foods. Root causes of spice contamination included contributions from both early and late stages of the farm-to-table continuum.  相似文献   
52.
Increased consumption of produce by consumers has been attributed to perceived health benefits of postharvest produce. Pathogen control is crucial because periodic occurrences and contamination of tomato and leafy greens have exacerbated food safety risks for consumers. We investigated the effects of temperatures (5 and 25 °C), storage time (30 min and 24 h) for inactivation of Listeria monocytogenes, Salmonella enterica and Escherichia coli O157:H7 by sophorolipid (SL‐p) produced fermentatively using palmitic acid as a co‐substrate at different concentrations in vitro. Reduction in pathogenic bacteria on grape tomato by SL‐p, sanitiser (Lovit) and combinations of SL‐p and sanitiser was determined. Temperature and storage time significantly (P < 0.05) affected pathogen inactivations by SL‐p as pathogen reductions were greater at 25 °C and 24 h than at 5 °C and 30 min of storage. L. monocytogenes was the most sensitive to SL‐p treatment as reductions of 5 log relative to untreated controls were attained at 0.12% of SL‐p. Significant reductions in S. enterica (1.91–3.85 logs) and E. coli O157:H7 (0.87–4.09 logs) were recorded at 2–5% of SL‐p. Lower populations of Salmonella and E. coli O157:H7 were inactivated than L. monocytogenes. On grape tomato, pathogen populations inactivated increased at higher SL‐p levels at 25 °C. Sanitiser and sanitiser + SL‐p reduced bacterial populations on tomato by 5.29–5.76 logs and 0.71–3.3.66 logs, respectively. These results imply the interactions of temperature, storage time and SL‐p significantly (P < 0.05) affected pathogen strain reductions. The combination of SL‐p with sanitiser led to synergistic effect on E. coli O157:H7, but not L. monocytogenes and S. enterica.  相似文献   
53.
We have used comparative sequence analysis to identify an intein-like sequence (protein splicing element) present in Cryptococcus neoformans, a fungal pathogen of humans. The sequence encoding this element is present in the C. neoformans PRP8 gene, as an in-frame insertion relative to the PRP8 genes of other organisms. It contains sequences similar to those of the protein-splicing domains of two previously described yeast inteins (in Saccharomyces cerevisiae and Candida tropicalis), although it lacks any recognizable internal endonuclease domain. The Cryptococcus neoformans intein (Cne PRP8) is only the second to be found in a eukaryote nuclear genome; the previously described yeast inteins occur at the same site in the VMA gene homologues of S. cerevisiae and C. tropicalis. The host gene of the Cryptococcus intein, PRP8, encodes a highly conserved mRNA splicing protein found as part of the spliceosome. The Cne PRP8 intein may be a useful drug target in addressing the cryptococcal infections so prevalent in AIDS patients.  相似文献   
54.
The objective of this study was to investigate the quality of milk from teats with milk flow disorders. Somatic cell count, pathogens, and signs of mastitis (>100,000 cells/ml and pathogens detected) were determined in the milk from all teats of the udder before treatment of the affected teat, as well as 1 and 6 mo later. Teats with milk flow disorders were compared to all of the other teats from the same udder. Before treatment, the SCC from affected teats was 4.3 million higher, the odds of detecting pathogens 6 times higher, and the odds of mastitis 11 times higher than in control teats (when adjusted for other significant explanatory variables). SCC and the risk of mastitis decreased after surgical treatment of the affected teats, whereas the chance of detecting pathogens was not affected. Six months after treatment, the SCC was 1.3 million higher, and the odds of mastitis 6.5 times higher than in control teats. Throughout the study period neither SCC, the odds of detecting pathogens, nor mastitis changed significantly in control teats. It may be concluded from this study that milk quality from teats with milk flow disorders is decreased before treatment and does not reach the milk quality from unaffected teats within 6 mo after treatment.  相似文献   
55.
医学领域中的新型生物传感器   总被引:3,自引:0,他引:3  
生物传感器作为一项新技术已广泛地应用于人体生化指标和各种病原体的检测,糖尿病和缺血一再灌注损伤病人的监测以及空间生命科学的在线监视等医学领域,它以准确,灵敏、高效,快速,设备简便和成本低等优点,逐渐成为近年来医学诊断监测技术的热点之一,对近年来国内外应用中医学领域中的新型生物传感器进行综述。  相似文献   
56.
The use of PCR-based techniques for directed gene alterations has become a standard tool in Saccharomyces cerevisiae. In our efforts to increase the speed of functional analysis of Candida albicans genes, we constructed a modular system of plasmid vectors and successfully applied PCR-amplified functional analysis (FA)-cassettes in the transformation of C. albicans. These cassettes facilitate: (a) gene disruptions; (b) tagging of 3'-ends of genes with green fluorescent protein (GFP); and (c) replacements of endogenous promoters to achieve regulated expression. The modules consists of a core of three selectable marker genes, CaURA3, CaHIS1 and CaARG4. Modules for C-terminal GFP-tagging were generated by adding GFP-sequences flanked at the 5'-end by a (Gly-Ala)3-linker and at the 3'-end by the S. cerevisiae URA3-terminator to these selection markers. Promoter exchange modules consist of the respective marker genes followed by the regulatable CaMAL2 or CaMET3 promoters at their 3'-ends. In order to ensure a reliably high rate of homologous gene targeting, the flanking homology regions required a size of 100 bp of gene-specific sequences, which were provided with the oligonucleotide primers. The use of shorter flanking homology regions produced unsatisfactory results with C. albicans strain BWP17. With these new modules only a minimal set of primers is required to achieve the functional analysis of C. albicans genes and, therefore, provides a basic tool to increase the number of functionally characterized C. albicans genes of this human pathogen in the near future.  相似文献   
57.
The antifungal effects of 22 essential oils from Turkish spices, herbs and citrus peel on four foodborne moulds were evaluated for fungistatic and fungicidal activity. The most active oils were wild thyme (Thymus rariflorus L) and thyme (Thymus serpyllum L). Parsley (Penloselinum sativum Hoffin) and savory (Satureja hortensis L) oils were found to be the least active oils. Rhizopus sp displayed the greatest tolerance, and the most sensitive mould was Penicillium chrysogenum. Prolonged incubations reduced the fungistatic and fungicidal effects of oils. It was concluded that some oils may be useful as mould inhibitors at food additive levels.  相似文献   
58.
目的: 研究多发性骨髓瘤(multiple myeloma, MM)患者住院化疗感染的临床特征,探讨感染的影响因素,为院内感染的防治提供依据。方法: 回顾性分析2012年1月至2016年3月嘉兴学院附属第一医院住院化疗的153例MM患者临床资料,研究感染的临床特征及影响因素。结果: 153例多发性骨髓瘤患者累计完成化疗415个疗程,其中150个疗程出现感染,占36.14%;常见的感染部位为呼吸道(49.25%)、消化道(16.42%)、泌尿道(13.43%)和口腔(7.46%)。共检出74株病原菌,其中革兰阴性菌占71.62%,革兰阳性菌占17.57%。Logistic多元回归分析显示,合并有糖尿病(95%CI:6.572-80.650,OR=22.359,P<0.001)、住院时间>20 d(95%CI:1.785-29.169,OR=17.328,P<0.001)、ISS分期高(95%CI:4.974-35.247,OR=12.894,P<0.001)是MM患者住院化疗感染的独立危险因素。结论: MM患者住院化疗容易并发各种病原菌感染,合并糖尿病、住院时间>20 d以及根据国际分期系统(ISS)分期高的患者感染发生率更高;对于合并有糖尿病、住院时间>20 d以及ISS分期高的患者应积极采取有效的预防和控制感染措施。  相似文献   
59.
This research aimed to detect Escherichia coli O157:H7 in milk based on immunomagnetic probe separation technology and quenching effect of gold nanoparticles to Rhodamine B. Streptavidin-modified magnetic beads (MBs) were combined with biotin-modified antibodies to capture E. coli O157:H7 specifically. Gold nanoparticle (AuNPs) was incubated with sulfhydryl-modified aptamers (SH-Aptamers) to obtain the Aptamers-AuNPs probe. After magnetic beads captured target bacteria and formed a sandwich structure with the gold nanoprobe, Rhodamine B was added into complex to obtain fluorescent signal changes. Our results demonstrated that the established method could detect E. coli O157:H7 in the range of 101–107 CFU/mL, and the limit of detection (LOD) was 0.35 CFU/mL in TBST buffer (pH = 7.4). In milk simulation samples, the LOD of this method was 1.03 CFU/mL. Our research provides a promising approach on the detection of E. coli O157:H7.  相似文献   
60.
Data from 274 Dutch herds recording clinical mastitis (CM) over an 18-mo period were used to investigate the effect of pathogen-specific CM on the lactation curve for somatic cell count (SCC). Analyzed pathogens were Staphylococcus aureus, coagulase-negative staphylococci, Escherichia coli, Streptococcus dysgalactiae, Streptococcus uberis, other streptococci, and the culture-negative samples. The dataset contained 178,754 test-day records on SCC, recorded in 26,411 lactations of 21,525 cows of different parities. In lactations without both clinical and subclinical mastitis, SCC was high shortly after parturition, decreased to a minimum at 50 days in milk (DIM), and increased slowly toward the end of the lactation. Effects of CM on lactation curves for SCC differed among the pathogens isolated. Before a case of clinical E. coli mastitis occurred, SCC was close to the SCC of lactations without both clinical and subclinical mastitis, and after the case of CM had occurred, SCC returned rather quickly to a low level again. Similar curves were found for lactations with cases of CM associated with culture-negative samples. Before a case of clinical Staph. aureus mastitis occurred, average SCC was already high, and it remained high after the occurrence. Effects of CM associated with Strep. dysgalactiae, Strep. uberis, and other streptococci on the lactation curve for SCC were comparable. They showed a continuous increase in SCC until the case of pathogen-specific CM occurred, and afterwards SCC stayed at a higher level. Using SCC test-day records, these typical characteristics of each pathogen may be used to find more effective indicators of CM.  相似文献   
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