Predictive value of plasma TMAO combined with NT-proBNP on the prognosis and length of hospitalization of patients with ischemic heart failure / 中华心血管病杂志

Objective: To explore the value of the assessment of plasma trimethylamine N-oxide (TMAO) combined with N-terminal pro-B-type natriuretic peptide (NT-proBNP) on predicting the all-cause mortality, length of hospitalization, and hospital cost in ischemic heart failure (IHF) patients. Methods: This prospective cohort study included 189 patients (157 males, mean age (64.0±10.5) years) with a left ventricular ejection fraction<45% caused by coronary artery disease, who hospitalized in our department from March 2016 to December 2020. Baseline data, including demographics, comorbid conditions and laboratory examination, were analyzed. The cumulative rate of all-cause mortality was evaluated using the Kaplan-Meier method and compared between the groups according to the log-rank test. Relative risks were reported as hazard ratios (HR) and 95% confidence interval (95%CI) calculated using the Cox proportional-hazards analysis, with stepwise adjustment for covariables. Spearman correlation analysis was then performed to determine the relationship between TMAO combined with NT-proBNP and length of hospitalization and hospital cost. Results: There were 50 patients in the low TMAO+low NT-proBNP group, 89 patients in high TMAO or high NT-proBNP group, 50 patients in high TMAO+high NT-proBNP group. The mean follow-up period was 3.0 years. Death occurred in 70 patients (37.0%), 27 patients (54.0%) in high TMAO+high NT-proBNP group, 29 patients (32.6%) in high TMAO or high NT-proBNP group and 14 patients (28.0%) in low TMAO+low NT-proBNP group. TMAO, in combination with NT-proBNP, improved all-cause mortality prediction in IHF patients when stratified as none, one or both biomarker(s) elevation, with the highest risk of all-cause mortality in high TMAO+high NT-proBNP group (HR=3.62, 95%CI 1.89-6.96, P<0.001). ROC curve analysis further confirmed that TMAO combined with NT-proBNP strengthened the prediction performance on the risk of all-cause death (AUC=0.727(95%CI 0.640-0.813), sensitivity 55.0%, characteristic 83.1%). Spearman correlation analysis showed that IHF patients with high TMAO and high NT-proBNP were positively associated with longer duration of hospitalization (r=0.191,P=0.009), but not associated with higher hospital cost (r=0.030, P=0.686). Conclusions: TMAO combined with NT-proBNP are valuable prediction tool on risk stratification of patients with IHF, and those with two biomarkers elevation face the highest risk of mortality during follow-up period, and are associated with the longer hospital stay.

Feature Extraction of Foot Movement Based on Plantar Pressure Distributions / 医用生物力学

Objective To analyze the statistical behavior of plantar pressure distribution, extract the characteristics of foot movement, and provide references for application of gait recognition in medical clinical diagnosis, rehabilitation training and public health. Methods The collected foot pressure data were prepossessed, statistical analysis on the data was performed, the footprint reconstruction was realized, and the pressure distribution rates of the footprints, segmented regions and each region were compared and analyzed, so as to decompose the foot motion characteristics. Results Based on the cross point of pressure peak curve in different regions, the plantar region was divided into toe region, metatarsal region, arch region and heel region, which could accurately extract the foot movement characteristics. Conclusions The peak plantar pressure is used to extract the characteristics of foot movement, which is divided into landing stage, whole foot contact stage, heel tiptoe stage and ground off stage.

Comparative study of dosimetry between volumetric-modulated arc therapy and intensity-modulated radiation therapy for brain metastases / 重庆医学

Objective To compare volumetric‐modulated arc therapy(VMAT) with intensity‐modulated radiation therapy (IMRT) for brain metastases with regard to the dosimetric character .Methods Sixty patients who were diagnosed with brain me‐tastases were included in this study .The target area received two dose levels using late addition amount technique ,WBRT (30 Gy/10 F) with following addition (20 Gy/10 F) to 59 Gy .For a fair comparison ,VMAT and IMRT treatment plans were respectively designed for every patient with the same dosimetric constraints .Dosimetric comparisons between VMAT and IMRT plans were ana‐lyzed to evaluate :target coverage and homogeneity ,conformity of PTV ;sparing of OARs ;monitor units (MUs) .Results Two treatment plans all reached the treatment need .When compared with IMRT ,there was no significant difference in Dmean of eyeball , len ,optic never ,visual chiasma ,parotid ,brain stem ,and external auditory canal of VMAT (P>0 .05) .The Dmax of eyeball ,len ,pa‐rotid ,and external auditory canal of VMAT were lower than that in IMRT group (P<0 .05) .The VMAT group has the less MUs (P=0 .017) and less treatment time .Conclusion VMAT can reach the big‐dose radiotherapy need on brain metastases clinically . There are no significant diffference between VMAT and IMRT on Dmax ,Dmean ,CI ,and HI .The Dmax of eyeball ,len ,parotid ,and external auditory canal of VMAT were lower than that in IMRT group .The VMAT can reduce the radiotherapy time .

The study of angular dependence of gamma index for Delta4 phantom / 中华放射肿瘤学杂志

Objective To study the effect of the uncertain deflection of the Delta4 phantom (ScandiDos AB,Sweden) in setting up on the Gamma index passing rate during the VMAT plan verification.Methods Two patients with head and neck cancer,two with lung cancers and one with pelvic cancer receiving VMAT radiotherapy were randomly chosen.By means of Eclipse8.6 TPS the treatment plans elaborated for the five patients were picked up to make the verification plans and Delta4 was used to perform dose verification On VARIAN Clinac Ⅸ.The Delta4 phantom was precisely set up first,and then it was deflected in a given angle towards the horizontal direction in relation to the center of the linear accelerator isocenter to perform the dose verification for 11 times successively.To figure out the relationship between the deflection angle of the Delta4 phantom and the Gamma index passing rate.Results As the Delta4 phantom was deflected by 0.0°,0.2°,0.4°,0.6°,0.8°,1.0°,1.2°,1.4°,1.6°,1.8° and 2.0° in sequence,the measured Gamma index passing rates presented a slight decline,but all greater than 90％ (DD 3％,DTA 3 mm).Conclusions In the VMAT plan verification,the Gamma index passing rate of Delta4 has no dependence on the uncertain deflection of the Delta4 phantom provided that the uncertain deflection of the Delta4 phantom is no greater than 2°,but the passing rates of DD and DTA vary significantly with the uncertain deflection of the Delta4 phantom.