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71.

Objectives

The aims of the present study were: 1) to investigate the contribution of the extent of luminal stenosis and other lesion composition-related factors in predicting invasive fractional flow reserve (FFR); and 2) to explore the distribution of various combinations of morphological characteristics and the severity of stenosis among lesions demonstrating normal and abnormal FFR.

Background

In patients with stable ischemic heart disease, FFR-guided revascularization, as compared with medical therapy alone, is reported to improve outcomes. Because morphological characteristics are the basis of plaque rupture and acute coronary events, a relationship between FFR and lesion characteristics may exist.

Methods

This is a subanalysis of NXT (HeartFlowNXT: HeartFlow Analysis of Coronary Blood Flow Using Coronary CT Angiography), a prospective, multicenter study of 254 patients (age 64 ± 10 years, 64% male) with suspected stable ischemic heart disease; coronary computed tomography angiography including plaque morphology assessment, invasive angiography, and FFR were obtained for 383 lesions. Ischemia was defined by invasive FFR ≤0.80. Computed tomography angiography–defined morphological characteristics of plaques and their vascular location were used in univariate and multivariate analyses to examine their predictive value for invasive FFR. The distribution of various combinations of plaque morphological characteristics and the severity of stenosis among lesions demonstrating normal and abnormal FFR were examined.

Results

The percentage of luminal stenosis, low-attenuation plaque (LAP) or necrotic core volume, left anterior descending coronary artery territory, and the presence of multiple lesions per vessel were the predictors of FFR. When grouped on the basis of degree of luminal stenosis, FFR-negative lesions had consistently smaller LAP volumes compared with FFR-positive lesions. The distribution of plaque characteristics in lesions with normal and abnormal FFR demonstrated that whereas FFR-negative lesions excluded likelihood of stenotic plaques with moderate to high LAP volumes, only one-third of FFR-positive lesions demonstrated obstructive plaques with moderate to high LAP volumes.

Conclusions

In addition to the severity of luminal stenosis, necrotic core volume is an independent predictor of FFR. The distribution of plaque characteristics among lesions with varying luminal stenosis and normal and abnormal FFR may explain the outcomes associated with FFR-guided therapy.  相似文献   
72.
Magnetic resonance imaging (MRI) of the sacroiliac (SI) joints and the spine is increasingly important in the assessment of inflammatory activity and structural damage in clinical trials with patients with ankylosing spondylitis (AS). We investigated inter-reader reliability and sensitivity to change of several scoring systems to assess disease activity and change in disease activity in patients with AS. Twenty sets of consecutive MRI, derived from a randomized clinical trial comparing an active drug with placebo and selected on the basis of the presence of activity at baseline, were presented electronically to 7 experienced readers from different countries (Europe, Canada). Readers scored the MRI by 3 different methods including: a global score (grading activity per SI joint); a more comprehensive global score (grading activity per SI joint per quadrant); and a detailed scoring system [Spondyloarthritis Research Consortium of Canada (SPARCC) scoring system], which scores 6 images, divided into quadrants, with additional scores for "depth" and "intensity." A fourth and a fifth scoring system were constructed afterwards. The fourth method included the SPARCC score minus the additional scores for "depth" and "intensity," and the fifth method included the SPARCC slice with the maximum score. Inter-reader reliability was investigated by calculating intraclass correlation coefficients (ICC) for all readers together and for all possible reader pairs. Sensitivity to change was investigated by calculating standardized response means (SRM) on change scores that were made positive. Overall inter-reader ICC per method were between 0.47 and 0.58 for scoring status, and between 0.40 and 0.53 for scoring change. ICC per possible reader pairs showed much more fluctuation per method, with lowest observed values close to zero (no agreement) and highest observed values over 0.80 (excellent agreement). In general, agreement of status scores was somewhat better than agreement of change scores, and agreement of the comprehensive SPARCC scoring system was somewhat better than agreement of the more condensed systems. Sensitivity to change differed per reader, but in general was somewhat better for the comprehensive SPARCC system. This experiment under "real life," far from optimal conditions demonstrates the feasibility of scoring exercises for method comparison, provides evidence for the reliability and sensitivity to change of scoring systems to be used in assessing activity of SI joints in clinical trials, and sets the conditions for further validation research in this field.  相似文献   
73.
PurposeThe diphtheria-tetanus-pertussis vaccine (DTP) and oral polio vaccine (OPV) were introduced in children 3 of 5 months of age in 1981–1983 in Bandim, in the capital of Guinea-Bissau. Because DTP has been linked to deleterious nonspecific effects (NSEs) and OPV to beneficial NSEs, we followed up this cohort to 3 years of age and examined the effects of DTP with OPV on all-cause mortality and the interactions of DTP and OPV with the measles vaccine (MV).MethodsDTP and OPV were offered at 3 monthly community weighing sessions. Vaccination groups were defined by the last vaccine received. We compared overall mortality for different groups in Cox proportional hazards regression models, reporting hazards ratios (HRs) with 95% CIs.FindingsThe study cohort included 1491 children born in Bandim from December 1980 to December 1983. From 3 to 35 months of age, with censoring for MV, children vaccinated with DTP and/or OPV had higher mortality than both unvaccinated children (HR = l.66; 95% CI, 1.03–2.69) and OPV-only vaccinated children (HR = 2.81; 95% CI, 1.02–7.69); DTP-only vaccinated children had higher mortality than OPV-only vaccinated children (HR = 3.38; 95% CI, 1.15-–9.93). In the age group of 3–8 months, before MV is administered, DTP-only vaccination was associated with a higher mortality than DTP with OPV (HR = 3.38; 95% CI, 1.59–7.20). Between 9 and 35 months of age, when MV is given, DTP-vaccinated and MV-unvaccinated children had higher mortality (HR = 2.76; 95% CI, 1.36–5.59) than children who had received MV after DTP, and among children who received DTP with MV or after MV, DTP-only vaccination was associated with a higher mortality than DTP with OPV (HR = 6.25; 95% CI, 2.55–15.37).ImplicationsBecause the 2 vaccines had differential effects and the healthiest children were vaccinated first, selection biases are unlikely to explain the estimated impact on child survival. OPV had beneficial NSEs, and administration of OPV with DTP may have reduced the negative effects of DTP.  相似文献   
74.
An increasing body of evidence connects alterations in the process of alternative splicing with cancer development and progression. However, a direct role of splicing factors as drivers of cancer development is mostly unknown. We analysed the gene copy number of several splicing factors in colon and lung tumours, and found that the gene encoding for the splicing factor SRSF6 is amplified and over‐expressed in these cancers. Moreover, over‐expression of SRSF6 in immortal lung epithelial cells enhanced proliferation, protected them from chemotherapy‐induced cell death and converted them to be tumourigenic in mice. In contrast, knock‐down of SRSF6 in lung and colon cancer cell lines inhibited their tumourigenic abilities. SRSF6 up‐ or down‐regulation altered the splicing of several tumour suppressors and oncogenes to generate the oncogenic isoforms and reduce the tumour‐suppressive isoforms. Our data suggest that the splicing factor SRSF6 is an oncoprotein that regulates the proliferation and survival of lung and colon cancer cells.  相似文献   
75.
Our aim was to determine the frequency of 12 common respiratory viruses in patients admitted to intensive care units with respiratory symptoms, evaluate the clinical characteristics and to compare the results to routine microbiological diagnostics. Throat swabs from 122 intensive care‐patients >18 years with acute respiratory symptoms were collected upon admission and analysed with multiplex real‐time polymerase chain reaction, for 12 community respiratory viruses. Blood and respiratory tract specimens were analysed for bacteria and fungi upon clinicians' request. Clinical and paraclinical data were collected. Viruses were detected in 19 (16%) of the 122 study patients. Five virus‐positive patients (26%) had possible clinically relevant bacteria or fungi co‐detected. Patients with exacerbation in COPD were associated with a viral infection (p = 0.02). Other comorbidities, clinical and paraclinical parameters, and death were independent of a viral infection or co‐detection of bacteria/fungi. In conclusion, respiratory viruses were frequently detected in the patients. The investigated clinical and paraclinical parameters were not different in viral infections compared to other agents, thus respiratory viruses likely have similar impact on the clinical course as other agents. In 25% of the virus‐positive patients, polymicrobial aetiology was identified. Comprehensive and sensitive diagnostic methods should be emphasized to enhance respiratory diagnostics.  相似文献   
76.
PurposeThe aim of this study was to evaluate the medium-term (5–9 years) and long-term (10–14 years) outcomes of mosaicplasty in the knee and identify possible risk factors for poor outcome.MethodsWe included patients 60 years or younger with symptomatic focal full-thickness chondral lesions. Seventy-three patients (87%) with median age of 34 years were available for analyses. Clinical outcome was evaluated by Lysholm score and VAS of pain.ResultsBoth the mean Lysholm score and mean VAS pain score improved significantly from baseline, 49 (SD 17) and 58 (SD 23), respectively, to both the mid-term follow-up, 72 (SD18, p < 0.001) and 27 (SD 20, p < 0.001), respectively, and the long-term follow-up, 72 (SD 21, p < 0.001) and 33 (SD 23, p < 0.001), respectively. A poor outcome at the long-term follow-up – defined as a Lysholm score of 64 or less or having had a knee replacement – was found in 40%. A poor outcome was more frequent in patients 40 years or older (59%), in women (61%) and in defects with an area of 3 cm2 or more (57%). Conversely, in a subgroup of male individuals younger than 40 years with defect size less than 3 cm2 the failure rate was 12.5% and the mean Lysholm score was 82 (SD 16).ConclusionWe conclude that the long-term clinical outcome after mosaicplasty varies greatly depending on age, gender and the size of the lesion.Level of evidenceIV-Retrospective Case Series.  相似文献   
77.
ObjectiveTo strengthen patients’ health literacy and their role as active knowledge actors, we developed a health communication intervention including a film-viewing and counselling session for patients awaiting kidney transplantation. We aimed to explore processes of knowing in the translation of the intervention.MethodsWe applied an ethnographic research approach, observing nine intervention sessions with patients and dialysis nurses. Afterwards, the patients and the nurses were interviewed in-depth. Data were analysed using Engebretsen’s modified version of Lonergans’ four-step model of knowing.ResultsThe following knowing processes were identified: i) Knowing as meaning-making; ii) Knowing as acquiring confidence; and iii) Accessing professionals’ and peer experts’ knowledge. Divergent considerations were taken by the different knowledge actors, which had a direct influence on the knowing processes and knowledge translation.ConclusionsThe findings support active interactions between patients and healthcare providers in processes of knowing. These include self-conscious approaches and critical questioning in both parties.Practice implicationsFor transplant professionals, this study demonstrates knowing processes in a real-life context. It also spotlights professional skills and attitudes regarding the importance of self-conscious questioning and a critical interrogating position (for both patients and providers).  相似文献   
78.
ObjectivesAssess the antibacterial, physical and chemical properties of AH Plus, BioRoot RCS and Pulp Canal Sealer (PCS) in contact with 2% chlorhexidine digluconate (CHX) used as final irrigant prior to root canal obturation.MethodsThe antimicrobial properties were investigated by direct contact tests for planktonic and biofilm growth of E. faecalis, S. mutans, S.epidermidis and S.aureus in vitro. The setting time, wettability, microhardness and surface roughness were also assessed. The sealers were studied in no contact, 1-minute (short-term) and continuous contact (long-term) with CHX. Chemical characterization of sealers was performed by scanning electron microscopy, X-ray diffraction analysis and Fourier-transform infrared spectroscopy after CHX or saline used as the last irrigant in an ex vivo tooth model and in endo training blocks.ResultsCHX increased the antibacterial activity of all the sealers investigated against planktonic bacteria and biofilms with PCS exerting the highest antimicrobial activity with and without the presence of CHX. The setting of AH Plus and BioRoot RCS was retarded, while for PCS accelerated in the presence of CHX. AH Plus and PCS were more hydrophilic after contact with CHX, whilst BioRoot RCS was hydrophobic in a time-dependent manner. The microhardness of sealers was compromised and the surface roughness increased after CHX exposure for AH Plus and BioRoot RCS, and decreased for PCS. CHX did not affect the sealers’ chemistry, but PCS that exhibited two extra phases.SignificanceCHX improved the antibacterial efficacy of endodontic sealers but further evidence is needed to confirm its suitability as a final irrigant prior to root canal obturation.  相似文献   
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