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91.
ObjectivesTo determine whether microbial contamination of preservation solution (PS) in kidney transplantation is associated with donor-derived infections (DDIs).MethodsWe retrospectively analysed data from 1077 deceased kidney transplant recipients of 560 donors. In all, 1002 PS samples were collected for microbiological assessment to establish the incidence and distribution of contamination. Comparisons between patients with contaminated PS and those with sterile PS were performed to assess the impact of microbial contaminations in perfusate on probable donor-derived infections (p-DDIs), and potential risk factors for p-DDIs were examined.ResultsThe contamination rate of PS was 77.8% (402/517). Bacterial species accounted for 85.6% (887/1036) of the total 1036 isolated microorganisms and 26.5% (275/1002) of the recipients' PS were contaminated by ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa and Enterobacter spp.). Enterococcus predominated the microbiological pattern. The incidence of infection was significantly higher in patients with microbial contamination than in patients with sterile PS (13.8% (107/776) versus 7.1% (16/226), p 0.006). The prevalence of p-DDIs was significantly higher in patients with ESKAPE contamination than in patients with other bacterial contamination in PS (7.2% (18/251) versus 1.0% (4/405), p 0.000). Univariate analysis indicated that ESKAPE contamination increased the risk of p-DDIs (p 0.001, OR 3.610, 95% CI 1.678–7.764). Multivariate analysis determined ESKAPE contamination as the only independent risk factor associated with p-DDIs (OR 3.418, 95% CI 1.580–7.393).ConclusionsThe high rate of microbial contaminations in PS is unusual and probably due to poor surgical procedures. Patients whose PS are contaminated by ESKAPE pathogens could have a significantly increased risk of p-DDIs at early post-transplantation.  相似文献   
92.
93.
94.
Lv  Sun-Liang  Zhang  Hui-Hui  Li  Jie-Yu  Hu  Wen-Qin  Song  Ya-Ting  Opriessnig  Tanja  Xiao  Chao-Ting 《Virus genes》2019,55(5):673-681

Astroviruses (AstV) are associated with enteric and systemic disease in mammals and birds. Astroviruses have received increased attention recently as they have been found to be associated with sporadic neurologic disease in mammals including humans. In pigs, porcine astrovirus (PoAstV) can be widely detected and has been grouped in five genotypes (PoAstV1 to PoAstV5). In the present study, we detected multiple PoAstVs in serum samples, nasal swabs, and fecal swabs collected from pigs suffering from respiratory disease or diarrhea but also from asymptomatic pigs, indicating a wide tissue tropism of the identified PoAstV genotypes. Coinfection of different genotypes in the same pig was commonly observed, and within an individual pig a high genetic diversity was observed for viruses belonging to the same PoAstV genotype. Two complete genomes of PoAstV2-WG-R2/2017 and PoAstV4-WG-R2/2017 were successfully obtained and characterized, with genome sizes of 6396 and 6643 nucleotides, respectively. The PoAstV2-WG-R2/2017 genome showed identities of 67.2–77.4% to other known PoAstV2 genomes, and the PoAstV4-WG-R2/2017 genome showed identities of 72.8–80.5% to other known PoAstV4 genomes. The predicted spike domain of open reading frame 2 (ORF2) of these strains showed the highest genetic heterogeneity, with amino acid identities of 13.7–70.9% for PoAstV2-WG-R2/2017 to other known PoAstV2 strains, and identities of 24.4–63.3% for the PoAstV4-WG-R2/2017 to other known PoAstV4 strains. Possible recombination events were identified in each of the two sequences. Two subclades of PoAstV2 and three subclades of PoAstV4 were defined in the present analyses. The obtained data provide further evidence for extraintestinal infectivity of PoAstVs, and confirmed the high genetic diversity of PoAstVs and the coinfection potential of different PoAstV types in a single pig.

  相似文献   
95.
Liu  Hualei  Wang  Jingjing  Ge  Shengqiang  Lv  Yan  Li  Yin  Zheng  Dongxia  Zhao  Yunling  Castellan  David  Wang  Zhiliang 《Virus genes》2019,55(3):314-321

Newcastle disease (ND) has been enzootic in China for several decades since the first recognition of the disease in 1946 in China. Continuous surveillance revealed that the sub-genotype VIId Newcastle disease virus (NDV) has been predominantly responsible for most of ND outbreak in China in recent years. But in the present study, three virulent NDVs isolated from poultry in southern China were classified as sub-genotype VIIh, which is highly related to the viruses circulating in some Southeast Asia countries. Continuous isolation of genotype VIIh NDV strains in the region suggests its panzootic potential. This is the first report of the sub-genotype VIIh NDVs in domestic poultry in China. The complete genome length of the three isolates was 15,192 nucleotides, and the motif at the cleavage site of F protein was 112RRRRR/F117 or 112RRRKR/F117, which was typical of virulent NDV. Phylogenetic analysis based on the F gene revealed that the three viruses had close relationship with the sub-genotype VIIh virus isolated from wild bird in 2011 in China. These viruses might have formed a stable lineage in poultry during 2012–2016 and have the potential to cause enzootic in China. Our study revealed the genetic and phylogenetic characteristics of the three sub-genotype VIIh isolates, which could help us to better understand the epidemiological context of these viruses.

  相似文献   
96.
重离子的细胞杀伤作用大,有倒转剂量分布优势,而且具有拓展布拉格峰、高传能线密度、高相对生物效应等特点。将其应用于癌症治疗,可使深部区域肿瘤细胞因高剂量辐射而被有效杀灭,而对周围组织因低剂量分布、相对危害较小,能实现精确靶向治疗,这也被认为是最有前景的肿瘤放疗技术。本文简要介绍了重离子放射治疗的物理和生物学特征,回顾了重离子放射治疗的发展历程及现状;重点阐述了重离子放射治疗技术在临床的应用现状及优势,以期为重离子辐射生物学的研究人员提供一定的数据参考和未来方向参考,更好地促进重离子放射治疗在临床治癌中的良好应用。  相似文献   
97.
Delayed encephalopathy after acute carbon monoxide (CO) poisoning (DEACMP) is the most severe and clinically intractable complication that occurs following acute CO poisoning. Unfortunately, the mechanism of DEACMP is still vague. Growing evidence indicates that delayed cerebral damage after CO poisoning is related to oxidative stress, abnormal neuro‐inflammation, apoptosis and immune‐mediated injury. Our recent report indicated that methylene blue (MB) may be a promising therapeutic agent in the prevention of neuronal cell death and cognitive deficits after transient global cerebral ischaemia (GCI). In this study, we aimed to investigate the potential of MB therapy to ameliorate the signs and symptoms of DEACMP. Rats were exposed to 1000 ppm CO for 40 min. in the first step; CO was then increased to 3000 ppm, which was maintained for another 20 min. The rats were implanted with 7‐day release Alzet osmotic mini‐pumps subcutaneously under the back skin, which provided MB at a dose of 0.5 mg/kg/day 1 hr after CO exposure. The results showed that MB significantly suppressed oxidative damage and expression of pro‐inflammatory factors, including tumour necrosis factor‐α and interleukin (IL)‐1β. MB treatment also suitably modulated mitochondrial fission and fusion, which is helpful in the preservation of mitochondrial function. Furthermore, MB dramatically attenuated apoptosis and neuronal death. Lastly, behavioural studies revealed that MB treatment preserved spatial learning and memory in the Barnes maze test. Our findings indicated that MB may have protective effects against DEACMP.  相似文献   
98.
侯超  吕鹏  白明学 《北方药学》2018,(7):134-137
目的:优化中药香囊的质量标准.方法:通过单因素法及正交实验法对药粉细度、载药量、棉花用量进行优化,确定中药香囊的质量标准.结果:中药香囊优化的质量标准为:药粉细度40目;载药量30g;棉花用量40g.结论:中药香囊通过优化质量标准,具有较好的灭菌作用.  相似文献   
99.

Objective

Current international and national guidelines for body mass index (BMI) and waist circumference (WC) have been recommended to all adults. However, whether recommendations applied to the oldest old (aged 80+) is poorly known. The study objective was to investigate the relation of BMI and WC with 3-year all-cause mortality among the oldest old.

Design, Setting, and Participants

A total of 4361 Chinese oldest old (mean age 91.8) participated in this community-based prospective cohort study.

Measurements

BMI and WC were measured at baseline in 2011 and were used as continuous variables and as categorized variables by recommendations or by tertiles. Adjusted, sex-stratified Cox models with penalized splines and Cox models were constructed to explore the association.

Results

Greater BMI and WC were linearly associated with lower mortality risk in both genders. The mortality risk was the lowest in overweight or obese participants (BMI ≥ 24.0) and was lower in participants with abdominal obesity. Compared to the upper tertile, those in the middle and lower tertile of BMI had a higher risk of mortality for men [hazard ratio (HR): 1.23 (1.02-1.48) and 1.53 (1.28-1.82)] and for women [HR: 1.21 (1.03-1.41) and 1.35 (1.15-1.58)]; it was also found in participants in the middle and lower tertile of WC for men [HR: 1.21 (1.01-1.46) and 1.41 (1.18-1.69)] and for women [HR: 1.35 (1.15-1.58) and 1.55 (1.32-1.81)] (all the P values for trend <.001). These findings were robust in further sensitivity analyses or when using propensity score matching, in subgroup analyses, or in octogenarians, nonagenarians, and centenarians.

Conclusions

In Chinese oldest old, both higher BMI and higher WC predict better survival in both genders. The finding suggests optimal BMI and WC may be sensitive to age, thus, the current recommendations for the oldest old may need to be revisited.  相似文献   
100.
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