老年呼吸机相关性肺炎患者肠道菌群特征及其与疾病的相关性

探讨老年呼吸机相关性肺炎(VAP)患者肠道菌群特征及其与疾病的相关性, 为该类患者的治疗提供参考。

选择2018年1月至2020年1月在该院进行机械通气的患者141例, 根据是否发生VAP分为VAP组(n=67)和非VAP组(n=74), 同时选择同期在我院进行体检的健康者为对照组(n=50)。采用16S rRNA荧光定量PCR法检测3组研究对象肠道双歧杆菌和大肠埃希菌数量, 并计算B/E值。采用流式细胞仪检测T淋巴细胞亚群CD3⁺、CD3⁺CD4⁺、CD3⁺CD8⁺、CD4⁺/CD25⁺、CD8⁺/CD28^-以及CD8⁺/CD28⁺细胞水平。采用改良酶学分光光度法检测血浆D-乳酸水平。采用Pearson相关检验分析VAP组B/E值与免疫功能及血浆D-乳酸的相关性。

VAP组患者肠道双歧杆菌数量、B/E值显著低于非VAP组和对照组, 大肠埃希菌数量显著高于非VAP组和对照组(均P < 0.05);非VAP组和对照组比较差异亦均有统计学意义(均P < 0.05)。VAP组患者CD3⁺、CD3⁺CD4⁺、CD3⁺CD8⁺以及CD8⁺CD28⁺细胞水平显著高于非VAP组和对照组, CD8⁺CD28^-细胞水平显著低于非VAP组和对照组(均P < 0.05);非VAP组和对照组比较差异亦均有统计学意义(均P < 0.05)。VAP组患者血浆D-乳酸水平显著高于非VAP组和对照组, 非VAP组和对照组比较差异亦有统计学意义(均P < 0.05)。Pearson相关检验显示, VAP组患者B/E值与CD3⁺、CD3⁺CD4⁺、CD3⁺CD8⁺、CD8⁺/CD28⁺细胞以及血浆D-乳酸水平呈显著负相关, 与CD8⁺/CD28^-细胞呈显著正相关(均P < 0.05)。

VAP患者存在肠道菌群失衡, 且VAP与肠道菌群失衡存在相关性, 促进肠道菌群平衡有助于VAP的防治。

     

Prolonged inhibitory effects against planktonic growth,adherence, and biofilm formation of pathogens causing ventilator-associated pneumonia using a novel polyamide/silver nanoparticle composite-coated endotracheal tube

Abstract

Microbial cells can rapidly form biofilm on endotracheal tubes (ETT) causing ventilator-associated pneumonia, a serious complication in patients receiving mechanical ventilation. A novel polyamide with a good balance of hydrophilic/hydrophobic moieties was used for the embedment of green-reduction silver nanoparticles (AgNPs) for the composite-coated ETT. The films were conformal with a thickness of ～ 17?±?3?µm accommodating high loading of 60?±?35?nm spherical-shaped AgNPs. The coated ETT resulted in a significant difference in reducing both planktonic growth and microbial adhesion of single and mixed-species cultures, compared with uncoated ETT (p?<?0.05). A time-kill assay demonstrated rapid bactericidal effects of the coating on bacterial growth and cell adhesion to ETT surface. Biofilm formation by Pseudomonas aeruginosa and Staphylococcus aureus, commonly encountered pathogens, was inhibited by > 96% after incubation for 72?h. Polyamide/AgNP composite-coated ETT provided a broad-spectrum activity against both Gram-positive and Gram-negative bacteria as well as Candida albicans and prolonged antimicrobial activity.     

Non-cytotoxic silver nanoparticle-polyvinyl alcohol hydrogels with anti-biofilm activity: designed as coatings for endotracheal tube materials

Endotracheal intubation is commonly associated with hospital-acquired infections as the intubation device acts as reservoir for bacterial colonization in the lungs. To reduce the incidence of bacterial colonization on the tubes, hydrogel coatings loaded with antimicrobial agents are gaining popularity. The aim of this study was to incorporate silver nanoparticles (AgNPs) into polyvinyl alcohol (PVA) to form stable hydrogels. Embedding AgNPs into PVA resulted in a decreased elongation at break and an increased tensile strength compared to PVA alone. The Ag release profile varied as a function of the degree of hydrolysis of PVA: the higher degree of hydrolysis demonstrated a lower release rate. Fourier infrared transform spectroscopy demonstrated that AgNPs interacted exclusively with the –OH groups of PVA. AgNP-loaded PVA was non-toxic against human normal bronchial epithelial cells while effective against the attachment of Pseudomonas aeruginosa and Staphylococcus aureus with a greater effect on P. aeruginosa.     

Modulation of glucose uptake in adipose tissue by nitric oxide-generating compounds

There is increasing evidence that endogenous nitric oxide (NO) influences adipogenesis, lipolysis and insulin-stimulated glucose uptake. We investigated the effect of NO released from S-nitrosoglutathione (GSNO) and S-nitroso N-acetylpenicillamine (SNAP) on basal and insulin-stimulated glucose uptake in adipocytes of normoglycaemic and streptozotocin (STZ)-induced diabetic rats. GSNO and SNAP at 0.2, 0.5, and 1 mM brought about a concentration-dependent increase in basal and insulin-stimulated 2-deoxyglucose uptake in adipocytes of normoglycaemic and STZ-induced diabetic rats. SNAP at 1.0 mM significantly elevated basal 2-deoxyglucose uptake (115.8 ± 10.4%) compared with GSNO at the same concentration (116.1 ± 9.4%;P 0.05) in STZ-induced diabetic rats. Conversely, SNAP at concentrations of 10 mM and 20 mM significantly decreased basal 2-deoxyglucose uptake by 50.0 ± 4.5% and 61.5 ± 7.2% respectively in adipocytes of STZ-induced diabetic rats (P 0.05). GSNO at concentrations of 10 mM and 20 mM also significantly decreased basal 2-deoxyglucose uptake by 50.8 ± 6.4% and 55.2 ± 7.8% respectively in adipocytes of STZ-induced diabetic rats (P 0.05). These observations indicate that NO released from GSNO and SNAP at 1 mM or less stimulates basal and insulin-stimulated glucose uptake, and at concentrations of 10 mM and 20 mM inhibits basal glucose uptake. The additive effect of GSNO or SNAP, and insulin observed in this study could be due to different mechanisms and warrants further investigation.     

非免疫抑制患者医院获得性肺炎及呼吸机相关肺炎病原菌组成及耐药性分析

目的分析非免疫抑制患者医院获得性肺炎及呼吸机相关肺炎临床特征、病原菌组成及耐药性,指导临床诊断及合理使用抗菌素。方法回顾性分析46例前瞻性观察诊断的非免疫抑制患者医院获得性肺炎及呼吸机相关肺炎临床及微生物学资料。结果平均起病时间为人院后（14．3±13．2）d,最常见基础疾病依次为脑血管意外（16／46）,慢性肺部疾病（13／46）和糖尿病（5／46）。培养阳性率58．7％,最常见细菌依次为鲍曼不动杆菌（8／27）、铜绿假单胞菌（6／27）、阴沟肠杆菌（3／29）及金黄色葡萄球菌（3／29）。80．4％患者入院72h内使用过抗生素,初始经验性治疗最常使用的抗菌素依次为头孢菌素（29／46）、碳青霉烯类（9／46）、糖肽类（5／46）。8株鲍曼不动杆菌对头孢哌酮／舒巴坦中介MIC〉32mg／L,对其他抗生素耐药;2株铜绿假单胞菌对美罗培南高度耐药MIC=128mg／L。结论非免疫抑制患者医院获得性肺炎及呼吸机相关肺炎多发生在有脑血管疾病及慢性肺疾病老年患者,我院非免疫抑制患者医院获得性肺炎及呼吸机相关肺炎最常见的病原菌多药耐药鲍曼不动杆菌,铜绿假单胞菌对碳青霉烯类耐药率较高。应优化医院获得性肺炎及呼吸机相关肺炎初始抗生素使用。     

机械通气患者呼吸机相关性肺炎临床分析与护理

目的探讨呼吸机相关性肺炎的临床相关因素及病原学特点,以指导临床防治。方法对100例呼吸机患者的呼吸机管路、下呼吸道感染病菌的菌种种类、呼吸机时间进行统计,分析与呼吸机相关性肺炎发病的因素。结果呼吸机管路和下呼吸道病原菌构成比具有同源性表现,呼吸机相关性肺炎发生率为36%,使用呼吸机时间长短与呼吸机相关性肺炎发生率呈正相关(P0.01)。结论呼吸机相关性肺炎与多种临床因素有关,使用时间越长,发病率越高。     

机械通气相关性肺炎患者病原体分布及 抗生素停药指征

目的了解机械通气相关性肺炎患者病原体分布特征,探讨降钙素原(PCT)在机械通气相关性肺炎(VAP)中对抗生素停药的指导价值。方法以在ICU行机械通气并被诊断为VAP的患者为研究对象,依据患者入组日期将患者随机分为观察组(37例)与对照组(35例)。采集患者痰液进行病原菌分离与药敏试验。观察组患者依据PCT水平决定抗生素停用时间,对照组患者依据临床医师经验决定抗生素停用时间。观察患者抗生素使用时间、PCT水平、肺部感染复发率及二重感染发生率等指标。结果 72例患者累计检出病原菌84株,其中12株为革兰阳性菌(14.33%),72株为革兰阴性菌(85.7%)。病原菌以肺炎克雷伯菌与铜绿假单胞菌最为常见,检出率分别为34.5%与31.0%,二者多重耐药率分别为44.8%与57.6%。抗生素治疗第8天时检测显示观察组与对照组患者PCT0.5ng/mL的比例分别为72.9%与71.4%,差异无统计学意义(χ2=0.021,P=0.885)。观察组患者VAP抗生素治疗平均时间为(9.8±3.2)d,显著短于对照组的(14.3±3.6)d,二者差异有统计学意义(t=5.612,P0.001)。多元线性回归分析结果显示,依据PCT水平停药是VAP抗生素治疗开始后28d内抗生素使用时间的独立影响因素(β=-8.24,95%CI:-11.37～-5.11,P0.001)。结论 VAP患者的病原菌以革兰阴性菌最为常见,铜绿假单胞菌与肺炎克雷伯菌感染高发,且二者多重耐药比例较高。PCT水平可作为VAP患者抗生素治疗停药判断标准,可有效减少抗生素使用时间。     

纳米银水凝胶涂膜干预气管导管表面铜绿假单胞菌黏附及生物膜形成的实验研究

目的研究纳米银水凝胶涂膜对气管导管（endotracheal tube,ETT）表面铜绿假单胞菌粘附及细菌生物膜（biofilm,BF）形成的干预作用。方法实验共设6组,分别为空白对照组,涂纳米银3．5、7．0、10．5、14．0和17．5μg／cm^2组。参考Brown平板法,制备ETT、表面铜绿假单胞菌BF模型。通过超声振荡-平板菌落计数法检测体外培养6、12、18h时各组ETT表面BF中的活细菌粘附数量。借助激光共聚焦显微镜观察BF中的活死菌分布情况,并测量BF厚度。结果（1）与空白对照组相比,最小量涂膜组（3．5μg／cm^2）体外培养6h时,导管表面活细菌的粘附量显著减少（P〈0．05）,12h时差异无显著性（P〉0．05）;最大量涂膜组（17．5μg／cm^2）体外培养6h时,ETT表面几乎未见细菌粘附（P〈0．05）,18h时BF中的活菌数量及BF厚度均显著减少（P〈0．05）。（2）激光共聚焦显微镜观察可见,培养6h时,空白对照组ETT表面粘附的死活菌呈不规则散点样分布,未见明显的细菌菌落形成,而各实验组ETT表面仅有细菌零星分布,其数量少于空白组。18h时空白对照组表面可见大量活死菌堆积粘连,有小菌落形成并相互交通成地图状,可见典型BF结构,而此时最大量涂膜组（17．5μg／cm^2）表面仅见数量不等的菌落形成,菌落周围可见数量不等的细菌分布。结论纳米银水凝胶涂膜可有效减少ETT表面铜绿假单胞菌的粘附数量,延缓导管表面细菌BF形成,其作用强弱随培养时间及单位面积中的纳米银剂量的变化而变化。     

新生儿呼吸机相关性肺炎病原菌分布及其耐药性分析

目的 了解新生儿重症监护室（NICU）患者呼吸机相关性肺炎（VAP）的病原菌特点及其耐药性,探讨其相应的防治措施,为针对VAP患者的抗菌药物治疗提供依据。方法 选择蚌埠医学院第一附属医院2015年1月至2017年1月NICU中使用呼吸机机械通气的57例患儿为研究对象,采用回顾性分析方法统计确诊为VAP的患儿的临床资料、病原菌构成,并对病原菌耐药情况进行分析。结果 共检出44株病原菌,革兰阴性菌所占比例为100.00%,未检出革兰阳性菌。检出率前3位的致病菌依次为鲍曼不动杆菌（36.36%,16/44）,铜绿假单胞菌（25.00%,11/44）,肺炎克雷伯杆菌（20.45%,9/44）。药敏试验结果显示,病原菌对氨苄西林/舒巴坦、头孢他啶、头孢唑啉等均耐药,且对亚胺培南、头孢曲松的药物敏感性明显下降。出生体重、1 min Apgar评分、插管次数、住院时间、机械通气时间、胎龄、母亲年龄、原发疾病为新生儿VAP发生的独立危险因素。结论 新生儿VAP致病菌以革兰阴性菌为主,且耐药率较高。新生儿VAP的发生与出生体重、胎龄、机械通气时间、插管次数等因素有关。     

Increase of nitrosative stress in patients with eosinophilic pneumonia

Background

Exhaled nitric oxide (NO) production is increased in asthma and reflects the degree of airway inflammation. The alveolar NO concentration (Calv) in interstitial pneumonia is reported to be increased. However, it remains unknown whether NO production is increased and nitrosative stress occurs in eosinophilic pneumonia (EP). We hypothesized that nitrosative stress markers including Calv, inducible type of NO synthase (iNOS), and 3-nitrotyrosine (3-NT), are upregulated in EP.

Methods

Exhaled NO including fractional exhaled NO (FE_NO) and Calv was measured in ten healthy subjects, 13 patients with idiopathic pulmonary fibrosis (IPF), and 13 patients with EP. iNOS expression and 3-NT formation were assessed by immunocytochemistory in BALf cells. The exhaled NO, lung function, and systemic inflammatory markers of the EP patients were investigated after corticosteroid treatment for 4 weeks.

Results

The Calv levels in the EP group (14.4 ± 2.0 ppb) were significantly higher than those in the healthy subjects (5.1 ± 0.6 ppb, p < 0.01) and the IPF groups (6.3 ± 0.6 ppb, p < 0.01) as well as the FE_NO and the corrected Calv levels (all p < 0.01). More iNOS and 3-NT positive cells were observed in the EP group compared to the healthy subject and IPF patient. The Calv levels had significant positive correlations with both iNOS (r = 0.858, p < 0.05) and 3-NT positive cells (r = 0.924, p < 0.01). Corticosteroid treatment significantly reduced both the FE_NO (p < 0.05) and the Calv levels (p < 0.01). The magnitude of reduction in the Calv levels had a significant positive correlation with the peripheral blood eosinophil counts (r = 0.802, p < 0.05).

Conclusions

These results suggested that excessive nitrosative stress occurred in EP and that Calv could be a marker of the disease activity.     

气管抽吸标本微生物检测在预测新生儿呼吸机相关性肺炎预后中的应用

目的 气管抽吸标本微生物检测在预测新生儿呼吸机相关性肺炎中的作用。方法 选择2016年4月—2018年4月本院NICU患儿359例,其中符合VAP诊断标准患儿172例,设为VAP组;不符合VAP诊断标准的患儿187例,设为对照组。检测呼吸道病原菌情况以及患儿预后。结果 对照组和VAP组的胎龄、出生体重、机械通气时间存在明显差异。VAP组中106例（61.63%）患儿为革兰阴性菌阳性,38例患儿为革兰阳性菌（22.09%）阳性,28例（16.28%）患儿为真菌阳性。革兰阴性菌中以肺炎克雷伯菌（20.93%）为主,其次是嗜麦芽窄食单胞菌（16.86%）。革兰阳性菌中以金黄色葡萄球菌（9.88%）和溶血葡萄球菌为主（5.81%）。鲍曼不动杆菌、肺炎克雷伯菌、嗜麦芽窄食单胞菌、金黄色葡萄球菌、白假丝酵母菌与VAP患儿死亡存在弱相关性。结论 NICU患儿因为机械通气引起上呼吸道或其他部位的病原菌定植于肺部引起VAP。部分细菌检出率增加预示患儿预后较差。     

重症监护病房呼吸机相关性肺炎中鲍曼不动杆菌耐药性的动态分析

目的探讨重症监护病房呼吸机相关性肺炎(VAP)中鲍曼不动杆菌(Acinetobacter baumannii,Ab)的分布特点和耐药性,为临床防治鲍曼不动杆菌感染提供依据。方法对机械通气>48 h的79例患者的气管抽吸物(ETA)进行细菌定量培养和药敏测定。结果回顾性分析79例VAP患者ETA培养出病原菌214株,其中鲍曼不动杆菌79株(36.9%)。鲍曼不动杆菌对常见抗菌药物的耐药率呈上升趋势,出现较多多重耐药和泛耐药菌株。头孢哌酮/舒巴坦和亚胺培南的耐药率分别是55.6%和68.4%,均呈上升趋势。结论鲍曼不动杆菌是VAP常见病原菌之一,鲍曼不动杆菌的耐药性呈上升趋势,特别是多重耐药和泛耐药菌株,应引起高度重视。     

In vivo detection of endotracheal tube biofilms in intubated critical care patients using catheter‐based optical coherence tomography

The formation of biofilms in the endotracheal tubes (ETTs) of intubated patients on mechanical ventilation is associated with a greater risk of ventilator‐associated pneumonia and death. New technologies are needed to detect and monitor ETTs in vivo for the presence of these biofilms. Longitudinal OCT imaging was performed in mechanically ventilated subjects at 24‐hour intervals until extubation to detect the formation and temporal changes of in vivo ETT biofilms. OCT‐derived attenuation coefficient images were used to differentiate between mucus and biofilm. Extubated ETTs were examined with optical and electron microscopy, and all imaging results were correlated with standard‐of‐care clinical test reports. OCT and attenuation coefficient images from four subjects were positive for ETT biofilms and were negative for two subjects. The processed and stained extubated ETTs and clinical reports confirmed the presence/absence of biofilms in all subjects. Our findings confirm that OCT can detect and differentiate between biofilm‐positive and biofilm‐negative groups (P < 10^?5). OCT image‐based features may serve as biomarkers for direct in vivo detection of ETT biofilms and help drive investigation of new management strategies to reduce the incidence of VAP.      

Accuracy of tracheal aspirate gram stain in predicting Staphylococcus aureus infection in ventilator-associated pneumonia

Background

The Gram stain can be used to direct initial empiric antimicrobial therapy when complete culture is not available. This rapid test could prevent the initiation of inappropriate therapy and adverse outcomes. However, several studies have attempted to determine the value of the Gram stain in the diagnosis and therapy of bacterial infection in different populations of patients with ventilator-associated pneumonia (VAP) with conflicting results. The objective of this study is to evaluate the accuracy of the Gram stain in predicting the existence of Staphylococcus aureus infections from cultures of patients suspected of having VAP.

Methods

This prospective single-center open cohort study enrolled 399 patients from December 2005 to December 2010. Patients suspected of having VAP by ATS IDSA criteria were included. Respiratory secretion samples were collected by tracheal aspirate (TA) for standard bacterioscopic analysis by Gram stain and culture.

Results

Respiratory secretion samples collected by tracheal aspirates of 392 patients were analyzed by Gram stain and culture. When Gram-positive cocci were arranged in clusters, the sensitivity was 68.4%, specificity 97.8%, positive predictive value 88.1% and negative predictive value 92.8% for predicting the presence of Staphylococcus aureus in culture (p < 0.001).

Conclusions

A tracheal aspirate Gram stain can be used to rule out the presence of Staphylococcus aureus in patients with a clinical diagnosis of VAP with a 92.8% Negative Predictive Value. Therefore, 7.2% of patients with Staphylococcus aureus would not be protected by an empiric treatment that limits antimicrobial coverage to Staphylococcus aureus only when Gram positive cocci in clusters are identified.     

添加益生菌的早期滋养量肠内营养对重症脑卒中患者呼吸机相关性肺炎的影响

目的 探讨早期给予添加益生菌的滋养量肠内营养（EN）对重症脑卒中患者呼吸机相关性肺炎（VAP）的影响。方法 选择2015年10月1日至2017年10月1日我院神经内科收治的接受鼻饲饮食及机械通气的重症脑卒中患者56例,随机分为对照组和观察组各28例。对照组患者在入院48 h内给予早期肠内营养支持治疗,观察组在对照组基础上常规给予双歧杆菌乳杆菌三联活菌片鼻饲,并给予滋养量肠内营养支持治疗（起始量10~20 mL鼻饲低速泵入）。比较两组患者治疗后肠内营养达标时间、肠内营养并发症发生率、营养状态指标、炎症因子水平、呼吸机相关性肺炎发生率、脱机成功率及病死率。结果 治疗后,观察组患者腹胀、腹泻、应激性高血糖发生率较低,肠内营养达标时间较短。同时观察组患者血清白蛋白、前白蛋白、淋巴细胞计数均高于对照组,血WBC、CRP、PCT水平均低于对照组。观察组患者脱机成功率相对较高,呼吸机相关性肺炎发生率相对较低。观察组患者GCS评分、APACHEⅡ评分及病死率相对较低,但差异均无统计学意义（P>0.05）。结论 早期给予添加益生菌的滋养量肠内营养有助于提高患者肠内营养的耐受性,改善患者营养状态,降低炎性因子水平,有助于减少呼吸机相关性肺炎发生率。     

Molecular Profiling of Innate Immune Response Mechanisms in Ventilator-associated Pneumonia

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Highlights

• •ETA present a diverse proteome and metabolome and can be employed for longitudinal studies of nosocomial infections affecting the lungs.
• •The proteome and metabolome of ETA and BAL share comparable features that may be leveraged for diagnostics.
• •ETA carries early signatures of host innate immunity against ventilator-associated pneumonia.

     

Efficacy of surface-generated nitric oxide against Candida albicans adhesion and biofilm formation

This report details the efficacy of nitric oxide (NO)-releasing xerogel surfaces composed of N-(6-aminohexyl)aminopropyl trimethoxysilane (AHAP3) and isobutyltrimethoxysilane (BTMOS) against Candida albicans adhesion, viability, and biofilm formation. A parallel plate flow cell assay was used to examine the effect of NO on planktonic fungal cells. Nitric oxide fluxes as low as 14 pmol cm^?2 s^?1 were sufficient to reduce fungal adhesion by ～49% over the controls after 90 min. By utilizing a fluorescence live/dead assay and replicate plating, NO flux was determined to reduce fungal viability in a dose-dependent manner. The formation of C. albicans biofilms on NO-releasing xerogel-coated silicon rubber (SiR) coupons was impeded when compared to control (non-NO-releasing) and bare SiR surfaces. The synergistic efficacy of NO and silver sulfadiazine against adhered fungal cells and biofilms is reported with increased killing and biofilm inhibition over NO alone.     

呼吸机相关性肺炎患者病原菌分布及血清HMGB1、PCT、CGRP水平变化的临床评价

探讨呼吸机相关性肺炎(VAP)患者感染病原菌分布情况以及血清高迁移率族蛋白B1(HMGB1)、降钙素原(PCT)、降钙素原基因相关肽(CGRP)水平的变化, 为该类患者的治疗提供参考。

选择2018年1月至2019年9月在我院接受治疗的机械通气患者137例, 其中符合VAP诊断标准的86例患者作为感染组, 其余51例作为未感染组; 选择同期在我院进行体检的60例健康者作为对照组。采用酶联免疫吸附法(ELISA)检测血清HMGB1、PCT、CGRP水平, 利用受试者工作曲线(ROC)预测血清HMGB1、PCT、CGRP对VAP的诊断价值。

137例机械通气治疗患者中有86例患者发生感染, 感染率为62.77%。86例感染患者样本共培养出95株致病菌, 其中革兰阴性菌(G^-)56株, 占58.95%;革兰阳性菌(G⁺)36株, 占37.89%;真菌3株, 占3.16%。感染组和未感染组患者血清HMGB1、PCT水平均高于对照组, CGRP水平低于对照组(均P < 0.05);感染组患者血清HMGB1、PCT水平均高于未感染组, CGRP水平低于未感染组(均P < 0.05)。ROC结果显示, 血清HMGB1、PCT、CGRP对VAP诊断的曲线下面积(AUC)分别为0.846、0.845、0.769, 最佳截断值分别为43.473μg/L、1.966μg/L、112.778 ng/L, 灵敏性分别为73.26%、65.12%、82.65%, 特异性分别为88.24%、94.12%、68.63%;三者联合诊断的AUC为0.932, 灵敏性和特异性分别为83.72%、94.12%。

VAP患者感染病原菌主要为革兰阴性菌。VAP患者血清HMGB1、PCT呈高表达, CGRP呈低表达, 三者对预测VAP均有一定效果, 其中三者联合诊断的效果最好, 具有一定的临床应用价值。

     

Comparative evaluation of nano-filled and conventional adhesives for bonding of molar tubes

It is of interest to compare the bonding characteristics of the two nano filled adhesives, Grandio (Voco, Cuxhaven, Germany) and Transbond Supreme LV (TSLV, 3M Unitek, Monrovia, California) with conventional bonding adhesive Transbond XT (TBXT, 3M Unitek) for bonding of molar tubes. 45 extracted human permanent molar teeth, divided into three groups of 15 each, were bonded with stainless steel molar tubes (3M Unitek, USA) using TBXT in Group 1, Grandio in Group 2, TSLV in Group 3. Remnant Index and shear bond strength was evaluated after 24 hrs. of storage with the aid of Instron Universal testing machine and Stereomicroscope respectively. Data were analysed using Analysis of Variance (ANOVA) test, Post-hoc Bonferroni test and Kruskal Wallis test. The mean SBS of Group 1(TBXT) was 13.86±3.27 MPa, Group 2 (Grandio) was 9.48±2.36 MPa and Group 3 (TSLV) was 11.64±2.71 MPa. Both nano-filled adhesives had SBS well above the clinically acceptable range. Assessment of ARI scores and type of bond failure revealed that adhesive failure for TBXT and TSLV and cohesive failure for Grandio. Nano-filled adhesives can be an appropriate substitute for the conventional adhesive for bonding of molar tubes.     

Electromagnetic irradiation of the terahertz diapason at nitric oxide frequencies for correction and prevention of disturbances of platelet functional activity in white rats during long-term stress

The effect of electromagnetic waves of the terahertz diapason at the frequencies of the molecular spectrum of irradiation and absorption of nitric oxide on the functional activity of platelets was studied in white rats submitted to a long-term stress. The course of action of terahertz frequency (THF) during the period of action of the stress was shown to prevent and restore disturbances of platelet aggregatory activity. Stress on animals submitted to a preventive course of THF action did not produce disturbances of the platelet functional activity characteristic of the stress reaction.