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1.
The aims of the study were to assess the clinical conformity between quantitative ultrasound (QUS) and densitometry with use of the standard World Health Organization T-score thresholds to determine optimal diagnostic cutoff values for QUS T-scores in different age groups. Three hundred sixty-five postmenopausal Caucasian women were enrolled into the study and divided into two age groups (<65 y and ≥65 y). Skeletal status was assessed using QUS measurements at the calcaneus and bone densitometry at the spine and proximal femur (Hologic Explorer, Bedford, MA, USA). QUS measurement results expressed as the stiffness index (SI) correlated significantly with both femoral neck bone mineral density (r = 0.51, p < 0.0001) and lumbar spine bone mineral density (r = 0.52, p < 0.0001). On the basis of receiver operating characteristic curve analyses, the thresholds for correspondence between QUS T-score values and T-score –2.5SD in dual X-ray absorptiometry (DXA) were established. They ranged between –1.63SD and –1.70SD in relation to femoral neck DXA and between –1.22SD and –1.51SD in relation to lumbar spine DXA, depending on age category. In conclusion, the study described here confirmed that QUS measurements at the calcaneus may provide information comparable to DXA examinations at the femoral neck and lumbar spine in postmenopausal women.  相似文献   
2.
BackgroundPatients with left breast cancer who undergo radiotherapy have a non-negligible risk of developing radiation-induced cardiovascular disease (CVD). Cardioprotection can be achieved through better treatment planning protocols and through respiratory gating techniques, including deep inspiration breath hold (DIBH). Several dosimetric studies have shown that DIBH reduces the cardiac dose, but clinical data confirming this effect is limited. The aim of the study was to compare the mean heart dose (MHD) in patients with left breast cancer who underwent radiotherapy at our institution as we transitioned from non-gated free-breathing (FB) radiotherapy to gated radiotherapy (FB-GRT), and finally to DIBH.Patients and methodsRetrospective study involving 2022 breast cancer patients who underwent radiotherapy at West Pomeranian Oncology Center in Szczecin from January 1, 2014 through December 31, 2017. We compared the MHD in these patients according to year of treatment and technique.ResultsOverall, the MHD for patients with left breast cancer in our cohort was 3.37 Gy. MHD values in the patients treated with DIBH were significantly lower than in patients treated with non-gated FB (2.1 vs. 3.48 Gy, p < 0.0001) and gated FB (3.28 Gy, p < 0.0001). The lowest MHD values over the four-year period were observed in 2017, when nearly 85% of left breast cancer patients were treated with DIBH. The proportion of patients exposed to high (> 4 Gy) MHD values decreased every year, from 40% in 2014 to 7.9% in 2017, while the percentage of patients receiving DIBH increased.ConclusionsCompared to free-breathing techniques (both gated and non-gated), DIBH reduces the mean radiation dose to the heart in patients with left breast cancer. These findings support the use of DIBH in patients with left breast cancer treated with radiotherapy.Key words: breast cancer, gated radiotherapy, deep inspiration breath hold, free breathing gated radiotherapy, mean heart dose  相似文献   
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BackgroundSteroid hormones play an important role in heart failure (HF) pathogenesis, and clinical data have revealed disordered steroidogenesis in male patients with HF. However, there is still a lack of studies on steroid hormones and their receptors during HF progression. Therefore, a porcine model of tachycardia-induced cardiomyopathy corresponding to HF was used to assess steroid hormone concentrations in serum and their nuclear receptor levels in heart tissue during the consecutive stages of HF.Methods and ResultsMale pigs underwent right ventricular pacing and developed a clinical picture of mild, moderate, or severe HF. Serum concentrations of dehydroepiandrosterone, testosterone, dihydrotestosterone, estradiol, aldosterone, and cortisol were assessed by enzyme-linked immunosorbent assay. Androgen receptor, estrogen receptor alpha, mineralocorticoid receptor, and glucocorticoid receptor messenger RNA levels in the left ventricle were determined by qPCR.The androgen level decreased in moderate and severe HF animals, while the corticosteroid level increased. The estradiol concentration remained stable. The quantitative real-time polymerase chain reaction revealed the downregulation of androgen receptor in consecutive stages of HF and increased expression of mineralocorticoid receptor messenger RNA under these conditions.ConclusionsIn the HF pig model, deteriorated catabolic/anabolic balance, manifested by upregulation of aldosterone and cortisol and downregulation of androgen signaling on the ligand level, was augmented by changes in steroid hormone receptor expression in the heart tissue.  相似文献   
4.
Biogerontology - Aging affects the energy metabolism differently in the cardiac and skeletal muscles. The study aim was to assess the effects of short-term calorie restriction (SCR) and refeeding...  相似文献   
5.
The aim of this study was to evaluate impact of 3D printed models on decision-making in context of laparoscopic liver resections (LLR) performed with intraoperative ultrasound (IOUS) guidance. Nineteen patients with liver malignances (74% were colorectal cancer metastases) were prospectively qualified for LLR or radiofrequency ablation in a single center from April 2017 to December 2018. Models were 3DP in all cases based on CT and facilitated optical visualization of tumors’ relationships with portal and hepatic veins. Planned surgical extent and its changes were tracked after CT analysis and 3D model inspection, as well as intraoperatively using IOUS. Nineteen patients were included in the analysis. Information from either 3DP or IOUS led to changes in the planned surgical approach in 13/19 (68%) patients. In 5/19 (26%) patients, the 3DP model altered the plan of the surgery preoperatively. In 4/19 (21%) patients, 3DP independently changed the approach. In one patient, IOUS modified the plan post-3DP. In 8/19 (42%) patients, 3DP model did not change the approach, whereas IOUS did. In total, IOUS altered surgical plans in 9 (47%) cases. Most of those changes (6/9; 67%) were caused by detection of additional lesions not visible on CT and 3DP. 3DP can be helpful in planning complex and major LLRs and led to changes in surgical approach in 26.3% (5/19 patients) in our series. 3DP may serve as a useful adjunct to IOUS. • 3D printing can help in decision-making before major and complex resections in patients with liver cancer. • In 5/19 patients, 3D printed model altered surgical plan preoperatively. • Most surgical plan changes based on intraoperative ultrasonography were caused by detection of additional lesions not visible on CT and 3D model.  相似文献   
6.
Introduction

With continuously growing number of redo bariatric surgeries (RBS), it is necessary to look for factors determining success of redo-surgeries.

Patients and methods

A retrospective cohort study analyzed consecutive patients who underwent RBS in 12 referral bariatric centers in Poland from 2010 to 2020. The study included 529 patients. The efficacy endpoints were percentage of excessive weight loss (%EWL) and remission of hypertension (HT) and/or type 2 diabetes (T2D).

Results

Group 1: weight regain

Two hundred thirty-eight of 352 patients (67.6%) exceeded 50% EWL after RBS. The difference in body mass index (BMI) pre-RBS and lowest after primary procedure < 10.6 kg/m2 (OR 2.33, 95% CI: 1.43–3.80, p = 0.001) was independent factor contributing to bariatric success after RBS, i.e., > 50% EWL.

Group 2: insufficient weight loss

One hundred thirty of 177 patients (73.4%) exceeded 50% EWL after RBS. The difference in BMI pre-RBS and lowest after primary procedure (OR 0.76, 95% CI: 0.64–0.89, p = 0.001) was independent factors lowering odds for bariatric success.

Group 3: insufficient control of obesity-related diseases

Forty-three of 87 patients (49.4%) achieved remission of hypertension and/or type 2 diabetes. One Anastomosis Gastric Bypass (OAGB) as RBS was independent factor contributing to bariatric success (OR 7.23, 95% CI: 1.67–31.33, p = 0.008), i.e., complete remission of HT and/or T2D.

Conclusions

RBS is an effective method of treatment for obesity-related morbidity. Greater weight regain before RBS was minimizing odds for bariatric success in patients operated due to weight regain or insufficient weight loss. OAGB was associated with greater chance of complete remission of hypertension and/or diabetes.

Graphical abstract
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Electrocardiographic (ECG) abnormalities in the setting of acute pulmonary embolism (PE) are being increasingly characterized and mounting evidence suggests that ECG plays a valuable role in prognostication for PE. We review the historical 21‐point ECG prognostic score for the severity of PE and examine the updated evidence surrounding the utility of ECG abnormalities in prognostication for severity of acute PE. We performed a literature search of MEDLINE, EMBASE, and PubMed up to February 2015. Article titles and abstracts were screened, and articles were included if they were observational studies that used a surface 12‐lead ECG as the instrument for measurement, a diagnosis of PE was confirmed by imaging, arteriography or autopsy, and analysis of prognostic outcomes was performed. Thirty‐six articles met our inclusion criteria. We review the prognostic value of ECG abnormalities included in the 21‐point ECG score, including new evidence that has arisen since the time of its publication. We also discuss the potential prognostic value of several ECG abnormalities with newly identified prognostic value in the setting of acute PE.  相似文献   
10.
In recent years, scientists have defined two main paths for orthopedic implant fabrication: searching for new materials with properties closest to natural bone in order to reduce the stress-shielding effect or creating individually adapted geometry of the implant with the use and Rapid Prototyping methods. Therefore, materials such as PEEK GRF30 and Ti6Al4V selective laser melting (SLM) are of interest. They are defined as materials suitable for implants, however, the knowledge of their bioactivity, a feature which is one of the most desirable properties of biomaterials, is still insufficient. Using Simulated Body Fluid and Hank’s Balanced Salt Solution, the bioactivity of PEEK GRF30 and Ti6Al4V SLM was assessed, as well as commercial Ti6Al4V as a reference material. Ten cylindrical samples of each material were prepared and immersed in solutions per period from 2 to 28 days at 37 °C. Optical analysis of the changes on the examined surfaces suggested that right after 2-day crystals with different morphologies were formed on each material. Further analysis of the chemical composition of the altered surfaces confirmed the formation of a calcium phosphate layer on them, however, the Ca/P ratio was slightly different from 1.67. On the basis of the obtained results, it can be concluded that both PEEK GRF30 and Ti6Al4V SLM are characterized by appropriate—comparable to Ti6Al4V—bioactivity.  相似文献   
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