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1.
ObjectivesOur aim was to evaluate the effect of the updated European Organization for Research and Treatment of Cancer (EORTC) and Mycoses Study Group 2019 definitions for invasive pulmonary aspergillosis (IPA) on patient classification and the related all-cause 12-week mortality.MethodsIn this retrospective cohort study from our tertiary care centre, we reclassified patients with haematological malignancy who underwent bronchoalveolar lavage between 2014 and 2019 for suspected IPA using the novel EORTC 2019 criteria. We performed receiver operating characteristic curve analysis to define the optimal cut-off for positive PCR and galactomannan and present survival analyses and their possible association with these diagnostic criteria through post hoc comparisons with log rank and Cox regression.ResultsFrom 323 episodes of suspected IPA in 282 patients, 73 were reclassified: 31 (42.5%) from possible to probable IPA, 5 (6.8%) from EORTC criteria not met to probable IPA, and 37 (50.7%) from EORTC criteria not met to possible IPA. Probable IPA increased therefore 11.1% (64/323, 19.8% to 100/323, 30.9%), mostly due to positive PCR (31/36, 86.1%). There was no difference in mortality between newly defined possible and probable IPA (log rank p = 0.950). Mortality was higher in probable cases with lower cycle thresholds (Ct values) versus higher Ct values (p = 0.004). Receiver operating characteristic curve analysis showed an optimal Ct value cut-off of 36.8 with a sensitivity of 75% (95% CI 64.9%–85.1%) and a specificity of 61.7% (95% CI 53.5–69.9) for 12-week mortality.DiscussionThe new EORTC criteria led to 11.1% more probable IPA diagnoses, mostly due to Aspergillus PCR. Restricting positive PCR to below a certain threshold might improve the discrimination of the new EORTC IPA categories for mortality.  相似文献   
2.
Defects of the cystic fibrosis (CF) transmembrane conductance regulator (CFTR) protein affect the homeostasis of chloride, bicarbonate, sodium, and water in the airway surface liquid, influencing the mucus composition and viscosity, which induces a severe condition of infection and inflammation along the whole life of CF patients. The introduction of CFTR modulators, novel drugs directly intervening to rescue the function of CFTR protein, opens a new era of experimental research. The review summarizes the most recent advancements to understand the characteristics of the infective and inflammatory pathology of CF lungs.  相似文献   
3.
Detecting Pneumocystis jirovecii by bronchoalveolar lavage or lung biopsy is the gold standard for diagnosis of P. jirovecii pneumonia (PJP); however, these techniques are not always applicable in children because of their high invasiveness. We report two pediatric cases of PJP diagnosed by polymerase chain reaction (PCR) of gastric lavage that were successfully treated. To date, there are no reported cases of using PCR of gastric lavage to diagnose PJP. On the day of PJP onset, both the infants required respiratory support and infiltrative shadows were observed in both lung fields on chest radiography. Furthermore, their (1 → 3)-β-D glucan levels were elevated. P. jirovecii was detected by PCR of gastric lavage and trimethoprim-sulfamethoxazole was administered for 3 weeks, following which their condition improved. They were long-term steroid users, but without any prophylaxis. PCR of gastric lavage in cases of suspected PJP may help in confirming the diagnosis in children who have mild to moderate airway symptoms, or have difficulty with invasive examination like bronchoscopy.  相似文献   
4.
《Vaccine》2019,37(22):2952-2959
CD8+ T cells are known to control infections, but their role in preventing latent infection from establishing has not been thoroughly investigated.We hypothesized that a potent CD8+ T cell response patrolling the mucosal viral entry points could kill the first infected cells and thereby abrogate the infection before latency is established.To investigate this, replication deficient adenovirus serotype 5 vectors encoding murine γ-herpesvirus-68 CD8+ T cell epitopes linked to the T cell adjuvant Invariant chain, were developed. We show that intranasal vaccination of mice reduces the risk of establishment of latent infection from multiple intranasal ID50 challenges with murine γ-herpesvirus-68 by 81% per exposure at 14 days post vaccination. Protection waned over time, but immune responses were extended by heterologous prime-boost vaccination applied simultaneously intramuscularly and intranasally, and animals vaccinated 66 days prior to challenge showed a strong trend of long-term protection.Our data provides evidence that CD8+ T cells are able to protect against establishment of latent infection. Although the protective efficacy is difficult to maintain over time, this proof-of-concept study suggests a role for a CD8+ T cell arm in future vaccine strategies against latent human viral infections caused by pathogens such as HIV and multiple herpes virus.  相似文献   
5.
In order to evaluate the in vivo effect of inhaled formulations, it is a gold standard to create a lung metastasis model by intravenously injecting cancer cells into an animal. Because the cancer grows from the blood vessel side, there is a possibility of underestimating the effect of an inhaled formulation administered to the lung epithelium side. In addition, the metastasis model has disadvantages in terms of preparation time and expense. The present study aimed to establish a new method to evaluate the effect of an inhaled small interfering RNA (siRNA) formulation that is more correct, more rapid, and less expensive. We investigated whether siRNA can suppress gene expression of plasmid DNA (pDNA) by serial pulmonary administration of siRNA and pDNA powders prepared by spray-freeze-drying. We revealed that formulations of dry siRNA powder significantly suppressed gene expression of pDNA powder compared with a control group with no siRNA. Naked siRNA inhalation powder with no vector showed the suppression of gene expression equivalent to that of an siRNA-polyethyleneimine complex without damaging tissues. These results show that the present method is suitable for evaluating the gene-silencing effect of inhaled siRNA powders.  相似文献   
6.
7.
Macrophages are the most abundant immune cells in the lung, which play an important role in COPD. The anti-inflammatory and anti-oxidation of ergosterol are well documented. However, the effect of ergosterol on macrophage polarization has not been studied. The objective of this work was to investigate the effect of ergosterol on macrophage polarization in CSE-induced RAW264.7 cells and Sprague-Dawley (SD) rats COPD model. Our results demonstrate that CSE-induced macrophages tend to the M1 polarization via increasing ROS, IL-6 and TNF-α, as well as increasing MMP-9 to destroy the lung construction in both RAW264.7 cells and SD rats. However, treatment of RAW264.7 cells and SD rats with ergosterol inhibited CSE-induced inflammatory by decreasing ROS, IL-6 and TNF-α, and increasing IL-10 and TGF-β, shuffling the dynamic polarization of macrophages from M1 to M2 both in vitro and in vivo. Ergosterol also decreased the expression of M1 marker CD40, while increased that of M2 marker CD163. Moreover, ergosterol improved the lung characters in rats by decreasing MMP-9. Furthermore, ergosterol elevated HDAC3 activation and suppressed P300/CBP and PCAF activation as well as acetyl NF-κB/p65 and IKKβ, demonstrating that HDAC3 deacetylation was involved in the effect of ergosterol on macrophage polarization. These results also provide a proof in immunoregulation of ergosterol for therapeutic effects of cultured C. sinensis on COPD patients.  相似文献   
8.
徐慧  陈敏  孙永峰  程星  王琦  靳蓉 《广东医学》2020,41(23):2394-2397
目的分析贵阳地区儿童重症社区获得性肺炎支气管肺泡灌洗液(BALF)病原学分布及耐药特点。方法收集989例重症社区获得性肺炎患儿临床资料,将支气管肺泡灌液采用支气管镜取出进行细菌培养、病毒以及肺炎支原体(MP)检测。结果(1)989例重症社区获得性肺炎患儿病原检出阳性716例,阳性率72.40%,细菌、病毒、支原体检出率分别33.27% (329例)、22.45%(222例)、31.45%(311例)。(2)细菌感染中的肺炎链球菌、金黄色葡萄球菌为最为常见的革兰阳性菌株(G+);而肺炎克雷伯菌、大肠埃希菌为最为常见的革兰阴性菌株(G-)。培养菌株对青霉素类、红霉素、第1、2、3代头孢类抗生素有较高的耐药性,对头孢吡肟、拉氧头孢、哌拉西林、左氧氟沙星有较高的敏感性,对亚胺培南、万古霉素、利奈唑烷均无耐药发生。(3)病毒感染检出222例,其中呼吸道合胞病毒131例,腺病毒检测49例,流感病毒6例(A型2例,B型4例),副流感病毒36例(1型3例、2型4例、3型29例),病毒检出率以0~12月龄组最高,RSV、ADV感染主要集中在冬春季节。(4)肺炎支原体检出阳性率31.45%(311例),肺炎支原体检出率以3~5岁组最高。结论贵阳地区重症肺炎中肺炎克雷伯杆菌、肺炎链球菌、大肠埃希菌、金黄色葡萄球菌为重要的细菌病原。重要病毒为腺病毒和呼吸道病毒为主,1~12月龄组的病毒感染检出率比较高。  相似文献   
9.
《Vaccine》2020,38(39):6141-6152
Influenza vaccination is considered the most valuable means to prevent and control seasonal influenza infections, which causes various clinical symptoms, ranging from mild cough and fever to even death. Among various influenza vaccine types, the inactivated subunit type is known to provide improved safety with reduced reactogenicity. However, there are some drawbacks associated with inactivated subunit type vaccines, with the main ones being its low immunogenicity and the induction of Th2-biased immune responses. In this study, we investigated the role of a single-stranded RNA (ssRNA) derived from the intergenic region in the internal ribosome entry site of the Cricket paralysis virus as an adjuvant rather than the universal vaccine for a seasonal inactivated subunit influenza vaccine. The ssRNA adjuvant stimulated not only well-balanced cellular (indicated by IgG2a, IFN-γ, IL-2, and TNF-α) and humoral (indicated by IgG1 and IL-4) immune responses but also a mucosal immune response (indicated by IgA), a key protector against respiratory virus infections. It also increases the HI titer, the surrogate marker of influenza vaccine efficacy. Furthermore, ssRNA adjuvant confers cross-protective immune responses against heterologous influenza virus infection while promoting enhanced viral clearance. Moreover, ssRNA adjuvant increases the number of memory CD4+ and CD8+ T cells, which can be expected to induce long-term immune responses. Therefore, this ssRNA-adjuvanted seasonal inactivated subunit influenza vaccine might be the best influenza vaccine generating robust humoral and cellular immune responses and conferring cross-protective and long-term immunity.  相似文献   
10.
Although radiation pneumonitis is usually confined to irradiated areas, some studies have reported that radiation-induced lymphocytic alveolitis can also spread to the non-irradiated lung. However, there have been few reports of radiation-induced eosinophilic alveolitis. We report the case of a 27-year-old female with radiation pneumonitis, occurring 4 months after radiation therapy for cancer of the left breast. Clinical and radiological relapse followed withdrawal of corticosteroids. Examination of bronchoalveolar lavage (BAL) in patchy airspace consolidations revealed increased eosinophil counts. Finally, clinical and radiological signs resolved rapidly after reintroduction of corticosteroids. Eosinophilic alveolitis may be promoted by radiation therapy. In the present case report, possible mechanisms for radiation-induced eosinophilic alveolitis are also reviewed.  相似文献   
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