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1.
《Cancer radiothérapie》2022,26(4):611-615
In order to provide more convenient irradiation regimens for patient comfort, radiation facility organization and health expenses, new hypofractionated protocols have been evaluated. Moderately (dose/fraction: 2.3 to 3 Gy), then ultra (dose/fraction: 5.2 to 6.1 Gy) hypofractionated irradiations were first validated. The current question is: is it possible to go forward using extreme hypofractionated regimens (EHR) based on 1 to 3 fractions. Different irradiation techniques are under investigation. However, brachytherapy remains the smartest way to deliver a high dose in a small volume. We report prospective and retrospective study results which evaluated EHR for breast and prostate brachytherapy. While oncological outcome and toxicity profile appear extremely encouraging for low-risk breast cancer after a 1 to 4 fractions (6.25 to 20 Gy/fraction), the use of a single fraction of 19 to 23 Gy appears debatable for prostate cancer. Brachytherapy represents an emblematic example of EHR but longer follow-up and more mature results are awaited in order to specify the right indications and refine the EQD2 calculation method including new biological and technical factors.  相似文献   
2.
BackgroundWe aimed to describe the effectiveness and safety of inhaled antibiotics in chronic obstructive pulmonary disease (COPD) patients, as well as the patient profile in which they are usually prescribed and the patient groups that can most benefit from this treatment.MethodsMulticentre retrospective observational cohort study in COPD patients who had received ≥1 dose of inhaled antibiotics in the last 5 years. Clinical data from the two years prior to and subsequent to the start of the treatment were compared. Primary outcome: COPD exacerbations. Secondary outcomes: side effects, symptomatology (sputum purulence, dyspnoea), microbiological profile and pathogen eradication.ResultsOf 693 COPD patients analyzed (aged 74.1; 86.3% men; mean FEV1 = 43.7%), 71.7% had bronchiectasis and 46.6% presented chronic bronchial infection (CBI) by Pseudomonas aeruginosa (PA). After 1 year of treatment with inhaled antibiotics, there was a significant decrease in the number of exacerbations (?33.3%; P < .001), hospital admissions (?33.3%; P < .001) and hospitalization days (?26.2%; P = .003). We found no difference in effectiveness between patients with or without associated bronchiectasis. Positive patient outcomes were more pronounced in PA-eradicated patients. We found a significant reduction in daily expectoration (?33.1%; P = .024), mucopurulent/purulent sputum (?53.9%; P < .001), isolation of any potentially pathogenic microorganisms (PPM) (?16.7%; P < .001), CBI by any PPM (?37.4%; P < .001) and CBI by PA (?49.8%; P < .001). CBI by any PPM and ≥three previous exacerbations were associated with a better treatment response. 25.4% of patients presented non-severe side-effects, the most frequent of these being bronchospasm (10.5%), dyspnoea (8.8%) and cough (1.7%).ConclusionsIn COPD patients with multiple exacerbations and/or CBI by any PPM (especially PA), inhaled antibiotics appear to be an effective and safe treatment, regardless of the presence of bronchiectasis.  相似文献   
3.
The aim of this study is to investigate the feasibility of manufacturing thin real-time relative dosimeters for clinical radiotherapy (RT) with potential applications for transmission monitoring in vivo dosimetry and pre-treatment dose verifications. Thin (≈1 μm) layers of a high sensitivity, wide bandgap semiconductor, the inorganic perovskite CsPbCl3, have been grown for the first time by magnetron sputtering on plastic substrates equipped with electrode arrays. Prototype devices have been tested in real-time configuration to evaluate the dose delivered by a 6 MV photon beam from a linear accelerator. Linearity of the charge with the dose has been verified over three order of magnitudes, linearity of the current signal with the dose rate has been also successfully tested in the range 0.5-4.3 Gy/min. The combination of high sensitivity per unit volume and wide bandgap provides high signal-to-noise ratios, up to 70, even at moderate applied voltages. The Schottky diode configuration allows the detector to operate without bias voltage (null bias).The blocking-barrier structure allows to confine the active volume within sub-millimetric sizes, a quite attractive feature in view to increase granularity and achieve the high spatial resolutions required in modern RT techniques. All the above-mentioned features indeed pave the way to a novel generation of flexible, transmission, real time dosimeters for clinical radiotherapy.  相似文献   
4.
Noninvasive imaging of cardiac fibrosis is important for early diagnosis and intervention in chronic heart diseases. Here, we investigated whether noninvasive, contrast agent-free MRI T2-mapping can quantify myocardial fibrosis in preclinical models of aging and pressure overload. Myocardial fibrosis and remodeling were analyzed in two animal models: (i) aging (15-month-old male CF-1 mice vs. young 6- to 8-week-old mice), and (ii) pressure overload (PO; by transverse aortic constriction in 4- to 5-month-old male C57BL/6 mice vs. sham-operated for 14 days). In vivo T2-mapping was performed by acquiring data during the isovolumic and early diastolic phases, with a modified respiratory and ECG-triggered multiecho TurboRARE sequence on a 7-T MRI. Cine MRI provided cardiac morphology and function. A quantitative segmentation method was developed to analyze the in vivo T2-maps of hearts at midventricle, apex, and basal regions. The cardiac fibrosis area was analyzed ex vivo by picro sirius red (PSR) staining. Both aged and pressure-overloaded hearts developed significant myocardial contractile dysfunction, cardiac hypertrophy, and interstitial fibrosis. The aged mice had two phenotypes, fibrotic and mild-fibrotic. Notably, the aged fibrotic subgroup and the PO mice showed a marked decrease in T2 relaxation times (25.3 ± 0.6 in aged vs. 29.9 ± 0.7 ms in young mice, p = 0.002; and 24.3 ± 1.7 in PO vs. 28.7 ± 0.7 ms in shams, p = 0.05). However, no significant difference in T2 was detected between the aged mild-fibrotic subgroup and the young mice. Accordingly, an inverse correlation between myocardial fibrosis percentage (FP) and T2 relaxation time was derived (R2 = 0.98): T2 (ms) = 30.45 – 1.05 × FP. Thus, these results demonstrate a statistical agreement between T2-map–quantified fibrosis and PSR staining in two different clinically relevant animal models. In conclusion, T2-mapping MRI is a promising noninvasive contrast agent-free quantitative technique to characterize myocardial fibrosis.  相似文献   
5.
ObjectiveEach pulmonary segment is an anatomical and functional unit. However, it is fundamentally difficult to precisely distinguish every pulmonary segment using the conventional pulmonary intersegmental planes from computed tomography images. Building arteriopulmonary segments is likely to be an effective way to identify pulmonary segments.MethodsThe thoracic computed tomography images of 40 patients were collected. The anatomic structures of interest were extracted in the transverse, sagittal, and coronal planes using the semi-automated segmentation tools provided by Amira software. The intrapulmonary vessels were subsequently segmented and reconstructed. The distributions of the pulmonary arteries, veins, and bronchi were observed. In patients with pulmonary masses, the mass was also reconstructed.ResultsThe three-dimensional reconstructed images showed the branches of the pulmonary artery ramified up to their eighth order covering the entire lung as well as evident intersegmental gaps without pulmonary arteries. The segmental artery was closely accompanied by the segmental bronchi in 486 pulmonary segments (90% of total number of segments). The size and spatial location of the pulmonary mass within a pulmonary segment were also clearly visible.ConclusionsDemarcation of arteriopulmonary segments can be used to precisely distinguish every pulmonary segment and provide its detailed anatomical structure before pulmonary segmentectomy.  相似文献   
6.
Lesbian, gay, bisexual, transgender, queer and two-spirit plus (LGBTQ2S+) people have distinct healthcare needs that may be unaddressed in many undergraduate healthcare curricula. The Radiation Therapy Program (RADTH) at the University of Alberta underwent a review of the three-year didactic curriculum using an online survey. The survey sought to ascertain if, where and how topics related to LGBTQ2S + healthcare are taught. Results indicated that out of 10 RADTH program faculty respondents, three teach related topics. The total time dedicated within the three-year curriculum was approximately three and a half hours. Other findings showed that faculty are interested in receiving more education in this area and would favour discussions about how to incorporate these themes into appropriate courses. This preliminary investigation demonstrated that there has been some initial work in this area, but there is more to be done.  相似文献   
7.
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   
8.
目的 通过分析特发性肺纤维化急性加重期(AE-IPF)患者证候与血清生物标志物的关系,为中医辨证治疗提供参考。方法 采用观察性研究设计,收集2019年3月至2019年11月三个中心的AE-IPF患者76例,其中痰热壅肺证26例、痰浊阻肺证50例,并纳入健康志愿者10例作为对照。采用ELISA测定患者血清CCL18、HMGB1、KL-6、MMP-7、SP-A和SP-D水平,分析与中医证候的相关性。结果 AE-IPF患者血清CCL18、HMGB1、KL-6、MMP-7、SP-A和SP-D水平均显著高于健康对照组。血清CCL18、HMGB1、KL-6、MMP-7和SP-D水平在痰热壅肺证和痰浊阻肺证患者间无显著性差异(P>0.05),而血清SP-A水平存在显著性差异(P<0.05)。结论 血清SP-A与AE-IPF证候存在一定的相关性,血清SP-A的浓度升高,与痰热壅肺证关系越密切,反之,血清SP-A浓度降低,则与痰浊阻肺证关系越密切。AE-IPF痰热壅肺证患者的预后可能较痰浊阻肺证患者更差。  相似文献   
9.
周敏  许震娟 《临床肺科杂志》2022,27(2):222-225,236
目的研究慢阻肺急性加重期患者延迟就医与家庭动力学的相关性,希望能够为慢阻肺急性加重期患者拟定护理措施提供科学依据。方法选取2017年1月-2019年12月我院240例诊断为慢阻肺急性加重期的患者为研究对象。根据患者入院就医的时间进行分组,时间≥24h的延迟就医的患者为观察组,时间<24h的及时就医患者为对照组。结果两组患者在文化水平、家庭年收入、在职状态、医疗保险和婚姻状况和APACHEⅡ评分比较(P<0.05)。观察组患者疾病观念、个性化、系统逻辑和家庭氛围得分比对照组高(P<0.05)。Pearman的相关性分析结果显示:慢阻肺急性加重期患者延迟就医时间与各个层面分数以及家庭动力总分呈现负相关性(P<0.05)。应变量为延迟就医为应变量,患者的一般资料为自变量,经Logistic回归分析结果表明:延迟就医的影响因素为文化水平、家庭动力评分、职业状态、家庭收入、婚姻状况和APACHEⅡ评分。结论慢阻肺急性加重期患者家庭动力总分与疾病观念、个性化、系统逻辑和家庭氛围得分与延迟就医时间呈现负相关性,患者延迟就医的影响因素是家庭动力学评分。  相似文献   
10.
目的 运用网络药理学方法及分子对接技术探讨黄芪干预腹膜纤维化的可能机制。方法 利用中药系统药理学数据库及分析平台(TCMSP)检索黄芪的主要化学成分及靶点,并补充文献报道相关药理作用的成分作为潜在活性成分。以"peritoneal fibrosis"为关键词分别在OMIM、Genecards获取目前已知的与腹膜纤维化相关的疾病靶点,后取两者的交集靶点;对交集基因通过STRING数据库与Cytoscape 3.7.2软件构建"药物-成分-靶点-疾病"网络及蛋白互作(PPI)网络并筛选核心网络。基于R软件使用Bioconductor生物信息软件对核心靶点进行GO及KEGG富集分析,最终采用AutoDock软件将主要有效成分与核心靶点进行分子对接,得出其结合能力。结果 筛选出20个黄芪活性成分及文献报道有相关药理作用4个, 457药物作用靶点,与674个腹膜纤维化病靶点取交集,得到86个共同靶点。GO功能富集分析提示黄芪拮抗腹膜纤维化主要参与了蛋白激酶B信号转导的调节、细胞对化学的应激反应、炎症反应的调节等通路; KEGG通路富集分析主要涉及调控肿瘤、磷脂酰肌醇-3-羟激酶-蛋白激酶B(PI3K-Akt)、晚期糖基化终末产物/晚期糖基化终末产物受体(AGE-RAGE)、人类巨细胞病毒感染、HIF-1信号通路等;分子对接结果显示关键靶点与活性成分具有较好的结合能力。结论 黄芪治疗腹膜纤维化的分子机制,可能与抑制炎症及氧化应激反应、调节多种信号通路等相关。  相似文献   
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