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1.
BackgroundThe treatment of patients after mechanical ventilation of lungs suffering from a multi-species infection of the tracheobronchial tree can be complicated.. The situation is aggravated in patients with post-intubation tracheal stenosis, where infection plays a leading pathogenetic role in damage to the tracheal wall. As a result of such a pathological process, cicatricial stenosis of the trachea of purulent-inflammatory infectious genesis or infected tracheal stenosis (ITS) may occur.MethodsIn this work, we studied the possibility of photodynamic inactivation of pathogenic microbiota typical for patients with ITS using methylene blue (MB) as a photosensitizer.Results13 clinical isolates of 8 species of bacteria from 9 patients were susceptible to photodynamic inactivation with MB. 30 μM of MB at a light irradiation dose of 25 J/cm2 and incubation with MB for 15 min allows to completely inactivate bacteria found in the tracheobronchial secretions of patients with ITS.ConclusionsMB retains its optico-physical properties in the range of 3–30 μM and provides effective inactivation of isolated Gram-positive and Gram-negative bacteria, including multi- and pan-resistant to antibiotics.  相似文献   
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《Clinical microbiology and infection》2022,28(9):1286.e1-1286.e8
ObjectiveAntibiotic susceptibility testing (AST) is necessary in order to adjust empirical antibiotic treatment, but the interpretation of results requires experience and knowledge. We have developed a machine learning software that is capable of reading AST images without any human intervention and that automatically interprets the AST, based on a database of antibiograms that have been clinically validated with European Committee on Antimicrobial Susceptibility Testing rules.MethodsWe built a database of antibiograms that were labelled by senior microbiologists for three species: Escherichia coli, Klebsiella pneumoniae, and Staphylococcus aureus. We then developed Antilogic, a Python software based on an original image segmentation module and supervised learning models that we trained against the database. Finally, we blind tested Antilogic against a validation set of 5100 photos of antibiograms.ResultsWe trained Antilogic against a database of 18072 pictures of antibiograms. Overall agreement against the validation set reached 97% (16 855/17 281) regarding phenotypes. The severity rate of errors was also evaluated: 1.66% (287/17 281) were major errors and 0.80% (136/17 281) were very major errors. After implementation of uncertainty quantifications, the rate of errors decreased to 0.80% (114/13 451) and 0.42% (51/13 451) for major and very major errors respectively.DiscussionAntilogic is the first machine learning software that has been developed for AST interpretation. It is based on a novel approach that differs from the typical diameter measurement and expert system approach. Antilogic is a proof of concept that artificial intelligence can contribute to faster and easier diagnostic methods in the field of clinical microbiology.  相似文献   
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摘要:目的 探讨儿童肺炎克雷伯菌血流感染(Klebsiella pneumoniae bloodstream infection, KPBSI)临床特征及肺炎克雷伯 菌(Klebsiella pneumoniae, KP)对常用抗菌药物的敏感性,为儿童KPBSI合理治疗提供参考。方法 回顾性分析2014年1月至2019 年12月在重庆医科大学附属儿童医院住院的KPBSI患儿临床资料。结果 共纳入110例患儿,64例(58.2%)为院内感染,72例 (65.5%)有基础疾病,以血液系统肿瘤最多见。110例患儿PRISM Ⅲ评分为16.0(7.0~20.8),其中74例(67.3%)发生脓毒症,15例 (13.6%)发生脓毒性休克,18例(16.4%)发生呼吸衰竭,15例(13.6%)需有创机械通气,院内死亡共13例(11.8%)。KP菌株对阿米卡 星、碳青霉烯类抗菌药物敏感率>90%,对头孢噻肟、头孢曲松和头孢他啶的敏感率分别为58.3%、60.9%和70.9%,对头孢哌 酮/舒巴坦和哌拉西林/他唑巴坦的敏感率分别为59.5%和82.7%。检出ESBLs+菌株39株(39/86,45.3%),耐碳青霉烯类肺炎克雷 伯菌(CRKP)菌株10株(10/110,9.1%),ESBLs+KP菌株和CRKP在各年龄组间分布无统计学差异。结论 儿童KPBSI多见于有基 础疾病的患儿,脓毒症、脓毒性休克和呼吸衰竭发生率高;KP菌株对头孢他啶和哌拉西林/他唑巴坦敏感性较高,可经验性治 疗轻症KPBSI患儿。  相似文献   
5.
Treatment guidelines for management of uncomplicated gonorrhoeae have been recently modified owing to alarming upsurge in azithromycin resistance. This study investigated the prevalence and genetic determinants of gonococcal azithromycin resistance in India. Four (5.7%) of 70 gonococcal isolates were resistant to azithromycin. Of 16 isolates investigated for molecular mechanisms of resistance, 13 (81.3%) and 6 (37.5%) isolates exhibited mutations in coding and promoter regions of mtrR gene, respectively. However, ermA, ermB and ermC genes or mutations in rrl gene were absent in all isolates. Azithromycin resistance is low in India posing no immediate threat to use of dual-therapy for syndromic management.  相似文献   
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摘要:畜禽养殖中抗菌药物的使用,导致其在畜禽体内残留带来食品安全问题。禽蛋是人类获取动物蛋白的重要来源之 一,禽蛋中蓄积的抗菌药物经食物链进入人体,威胁人类健康。目前,禽蛋中抗菌药物的残留状况未见有综合性、系统性的归 纳总结。本文总结了2001-2019年国内外文献及2018-2019年我国市场监督管理总局网站中报道的禽蛋抗菌药物残留情况总 结。分析了分药物类别对禽蛋中残留的抗菌药物阳性率及残留量现状,为抗菌药物的监管及食品安全的保障提供参考。  相似文献   
7.
IntroductionAnti-methicillin-resistant Staphylococcus aureus (MRSA) agents have different doses and administration periods. Thus, it is difficult to evaluate antimicrobial use (AMU) of anti-MRSA agents using defined daily doses per 1000 inhabitants per day (DID) or days of therapy per 1000 inhabitants per day (DOTID). This study aimed to evaluate the relationship between anti-MRSA agent use and resistant bacteria using the number of patients per 1000 inhabitants per day (PID) as an alternative index of AMU.MethodsAMU data for anti-MRSA agents were collected from the National Database of Health Insurance Claims and Specific Health Checkups (NDB) in 2016. The relationship between PID and DID or DOTID was evaluated. The number of patients with MRSA isolated was obtained from Japan Nosocomial Infections Surveillance, and their correlation with PID was analyzed. The rate of anti-MRSA agent use in each prefecture was investigated.ResultsPID showed a significant linear relationship with both DID and DOTID (all p < 0.0001). PID was significantly correlated with the number of patients with MRSA isolated. Additionally, the rate of anti-MRSA agent use was markedly different in each region.ConclusionsPID is not affected by doses and administration periods, and thus may be an alternative index for the selective pressure of antibiotics. Evaluating AMU using PID based on NDB data will help in the development of effective antimicrobial resistance measures.  相似文献   
8.
ObjectivesDespite its use in determining nigrostriatal degeneration, the lack of a consistent interpretation of nigrosome 1 susceptibility map-weighted imaging (SMwI) limits its generalized applicability. To implement and evaluate a diagnostic algorithm based on convolutional neural networks for interpreting nigrosome 1 SMwI for determining nigrostriatal degeneration in idiopathic Parkinson's disease (IPD).MethodsIn this retrospective study, we enrolled 267 IPD patients and 160 control subjects (125 patients with drug-induced parkinsonism and 35 healthy subjects) at our institute, and 24 IPD patients and 27 control subjects at three other institutes on approval of the local institutional review boards. Dopamine transporter imaging served as the reference standard for the presence or absence of abnormalities of nigrosome 1 on SMwI. Diagnostic performance was compared between visual assessment by an experienced neuroradiologist and the developed deep learning-based diagnostic algorithm in both internal and external datasets using a bootstrapping method with 10000 re-samples by the “pROC” package of R (version 1.16.2).ResultsThe area under the receiver operating characteristics curve (AUC) (95% confidence interval [CI]) per participant by the bootstrap method was not significantly different between visual assessment and the deep learning-based algorithm (internal validation, .9622 [0.8912–1.0000] versus 0.9534 [0.8779-0.9956], P = .1511; external validation, 0.9367 [0.8843-0.9802] versus 0.9208 [0.8634-0.9693], P = .6267), indicative of a comparable performance to visual assessment.ConclusionsOur deep learning-based algorithm for assessing abnormalities of nigrosome 1 on SMwI was found to have a comparable performance to that of an experienced neuroradiologist.  相似文献   
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PurposeTo determine the association between antifungal susceptibility test (AFST) results and in vivo therapeutic response in Indian patients with fungal rhinosinusitis.MethodsThe clinicoradiological, fungal culture, AFST, histopathology results and outcomes of 48 patients with fungal rhinosinusitis seen between 20132015 were analysed. Minimum inhibitory concentration (MIC) determination was performed for amphotericin B, itraconazole, voriconazole and posaconazole.ResultsForty patients had invasive and 8 had non-invasive fungal sinusitis. Rhizopus and Aspergillus species which comprised 46.9% each of isolates were mostly associated with acute invasive fungal rhinosinusitis and chronic granulomatous fungal rhinosinusitis respectively. All patients with non-invasive fungal rhinosinusitis had Aspergillus isolates.The Geometric Mean (GM) MIC for R. arrhizus of amphotericin B and posaconazole was 0.51 mcg/mL and 3.08 mcg/mL respectively and for A. flavus species for amphotericin B and voriconazole values were 1.41mcg/mL and 0.35 mcg/mL respectively.In patients with Aspergillus infections, while there was no association of MICs for azoles and outcome (p = 1), a strong association was noted between azole therapy and a good outcome (p = 0.003). In patients with Rhizopus infections, no association was found between MICs for amphotericin B and outcome (p = 1) and because of therapeutic complications, no association was found between amphotericin B therapy and outcome (p = 1).ConclusionNo significant association exists between in vitro (AFST) and in vivo responses despite low GM MICs for the drugs used in Aspergillus and Rhizopus infections. Therapeutic complications following conventional amphotericin B therapy confounds analysis. Clinical responses suggest that azoles are the drug of choice for Aspergillus infections.  相似文献   
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