[Application of ultra-short echo time-T2* component analysis technology in monitoring morphological and biochemical changes of achilles tendon in amateur marathon athletes]

Objective: To explore the value of ultra-short echo time (UTE)-T₂* component analysis techniques in dynamic monitoring the morphological and biochemical changes in amateur marathon athletes' achilles tendon before and after the marathon. Methods: Twenty-nine amateur marathon runners were recruited between October 2020 and March 2021 in Zhuhai City, Guangdong Province, including 25 males and 4 females, aged from 24 to 50 (40±6) years old. All volunteers underwent bilateral achilles tendon MRI examination 1 week before the marathon, 48 hours after the race, and 1 month after the race. The shape and signal of the achilles tendon were evaluated by routine T1-weighted, proton density weighted with fat saturation sequence and different echo time (TE) UTE sequence, and the changes of achilles tendon after running was quantitatively analyzed by UTE-T2* sequence. The values of single-component analysis (T₂*_M), short T₂* components (T₂*_S), and long T₂* components (T₂*_L) and Fraction values were obtained using UTE-T₂* sequence. The value of the whole achilles tendon was measured on the sagittal images of achilles tendon, and the Achilles tendon was equally divided into three subregions [muscle-tendon junction (MTJ), middle (MID), and insertion (INS)]. The region of interest was delineated by two radiologists independently. The intra-group correlation coefficient (ICC) was used to evaluate the consistency of the data measured by two radiologists. Nonparametric Friedman M test was used to compare the differences of T₂*_M, T₂*_S, T₂*_L and Fraction values in different time points and different subregions. Wilcoxon rank-sum test was used to compare the difference between 48 h post-race and pre-race T₂*_S values (ΔT₂*_S) of different distance, different running posture, different pace and different amount of training, in which ΔT₂*_S equals the T₂*_S value of 48 h post-race minus the T₂*_S value of pre-race. Results: On the sequence of short TE (TE≤0.6 ms), achilles tendinopathy can manifest as scattered punctate hypointensity in areas of high signal intensity. The two radiologists showed a good consistency in measuring the T₂*_M, T₂*_S, T₂*_L and Fraction values of the achilles tendon, and the ICC values ​​were 0.96, 0.94, 0.83 and 0.94, respectively. The T₂*s values was significantly higher in the whole Achilles tendon, MTJ and MID segment at 48 h post-exercise compared to pre-exercise, and decreased after 1 month of exercise, [0.49 (0.45, 0.59) vs 0.54 (0.49, 0.59) vs 0.53 (0.49, 0.57), 0.48 (0.44, 0.54) vs 0.53 (0.47, 0.58) vs 0.50 (0.46, 0.57), 0.48 (0.43, 0.58) vs 0.54 (0.47, 0.59) vs 0.52 (0.46, 0.57); respectively, all P<0.05]. The changes in T₂*_M, T₂*_L and Fraction values are not statistically significant (all P>0.05). In different running gestures, the ΔT₂*_S of achilles tendon who using the postures of front-middle feet is higher than that using the postures of back feet (0.03(-0.05, 0.07) vs -0.03(-0.17, 0.11), P=0.001). Conclusion: The Bi-component analysis of UTE-T₂* technology is superior to single component analysis in monitoring the dynamic changes of achilles tendon before and after exercise, and T₂*_S is a more sensitive sequence to evaluate the subtle changes in the chemical composition of achilles tendon.

Opportunistic Screening Using Low-Dose CT and the Prevalence of Osteoporosis in China: A Nationwide, Multicenter Study

Opportunistic screening for osteoporosis can be performed using low-dose computed tomography (LDCT) imaging obtained for other clinical indications. In this study we explored the CT-derived bone mineral density (BMD) and prevalence of osteoporosis from thoracic LDCT in a large population cohort of Chinese men and women. A total of 69,095 adults (40,733 men and 28,362 women) received a thoracic LDCT scan for the purpose of lung cancer screening between 2018 and 2019, and data were obtained for analysis from the China Biobank Project, a prospective nationwide multicenter population study. Lumbar spine (L₁ -L₂ ) trabecular volumetric bone mineral density (vBMD) was derived from these scans using quantitative computed tomography (QCT) software and the American College of Radiology QCT diagnostic criteria for osteoporosis were applied. Geographic regional differences in the prevalence of osteoporosis were assessed and the age-standardized, population prevalence of osteoporosis in Chinese men and women was estimated from the 2010 China census. The prevalence of osteoporosis by QCT for the Chinese population aged >50 years was 29.0% for women and 13.5% for men, equating to 49.0 million and 22.8 million, respectively. In women, this rate is comparable to estimates from dual-energy X-ray absorptiometry (DXA), but in men, the prevalence is double. Prevalence varied geographically across China, with higher rates in the southwest and lower rates in the northeast. Trabecular vBMD decreased with age in both men and women. Women had higher peak trabecular vBMD (185.4 mg/cm³ ) than men (176.6 mg/cm³ ) at age 30 to 34 years, but older women had lower trabecular vBMD (62.4 mg/cm³ ) than men (92.1 mg/cm³ ) at age 80 years. We show that LDCT-based opportunistic screening could identify large numbers of patients with low lumbar vBMD, and that future cohort studies are now required to evaluate the clinical utility of such screening in terms of fracture prevention and supporting national health economic analyses. © 2020 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR)..

Quantitative image analysis for evaluation of tumor response in clinical oncology

The objective, accurate, and standardized evaluation of tumor response to treatment is an indispensable procedure in clinical oncology. Compared to manual measurement, computer-assisted linear measurement can significantly improve the accuracy and reproducibility of tumor burden quantification. For irregular-shaped and infiltrating or diffuse tumors, which are difficult to quantify by linear measurement, computer-assisted volumetric measurement may provide a more objective and sensitive quantification to evaluate tumor response to treatment than linear measurement does. In the evaluation of tumor response to novel oncologic treatments such as targeted therapy, changes in overall tumor size do not necessarily reflect tumor response to therapy due to the presence of internal necrosis or hemorrhages. This leads to a new generation of imaging biomarkers to evaluate tumor response by using texture analysis methods, also called radiomics. Computer-assisted texture analysis technology offers a more comprehensive and in-depth imaging biomarker to evaluate tumor response. The application of computer-assisted quantitative imaging analysis techniques not only reduces the inaccuracy and improves the reliability in tumor burden quantification, but facilitates the development of more comprehensive and intelligent approaches to evaluate treatment response, and hence promotes precision imaging in the evaluation of tumor response in clinical oncology. This article summarizes the state-of-the-art technical developments and clinical applications of quantitative imaging analysis in evaluation of tumor response in clinical oncology.

Preliminary Study of MR and Fluorescence Dual-mode Imaging: Combined Macrophage-Targeted and Superparamagnetic Polymeric Micelles

Purpose: To establish small-sized superparamagnetic polymeric micelles for magnetic resonance and fluorescent dual-modal imaging, we investigated the feasibility of MR imaging (MRI) and macrophage-targeted in vitro. Methods: A new class of superparamagnetic iron oxide nanoparticles (SPIONs) and Nile red-co-loaded mPEG-Lys3-CA4-NR/SPION polymeric micelles was synthesized to label Raw264.7 cells. The physical characteristics of the polymeric micelles were assessed, the T2 relaxation rate was calculated, and the effect of labeling on the cell viability and cytotoxicity was also determined in vitro. In addition, further evaluation of the application potential of the micelles was conducted via in vitro MRI. Results: The diameter of the mPEG-Lys3-CA4-NR/SPION polymeric micelles was 33.8 ± 5.8 nm on average. Compared with the hydrophilic SPIO, mPEG-Lys3-CA4-NR/SPION micelles increased transversely (r2), leading to a notably high r2 from 1.908 µg/mL-1S-1 up to 5.032 µg/mL-1S-1, making the mPEG-Lys3-CA4-NR/SPION micelles a highly sensitive MRI T2 contrast agent, as further demonstrated by in vitro MRI. The results of Confocal Laser Scanning Microscopy (CLSM) and Prussian blue staining of Raw264.7 after incubation with micelle-containing medium indicated that the cellular uptake efficiency is high. Conclusion: We successfully synthesized dual-modal MR and fluorescence imaging mPEG-Lys3-CA4-NR/SPION polymeric micelles with an ultra-small size and high MRI sensitivity, which were effectively and quickly uptaken into Raw 264.7 cells. mPEG-Lys3-CA4-NR/SPION polymeric micelles might become a new MR lymphography contrast agent, with high effectiveness and high MRI sensitivity.

Effect of PEG-PDLLA polymeric nanovesicles loaded with doxorubicin and hematoporphyrin monomethyl ether on human hepatocellular carcinoma HepG2 cells in vitro

Objective

To evaluate the cytotoxicity of poly(ethylene glycol)-block-poly(D,L-lactic acid) (PEG-PDLLA) nanovesicles loaded with doxorubicin (DOX) and the photosensitizer hematoporphyrin monomethyl ether (HMME) on human hepatocellular carcinoma HepG2 cells and to investigate potential apoptotic mechanisms.

Methods

PEG-PDLLA nanovesicles were simultaneously loaded with DOX and HMME (PEG-PDLLA-DOX-HMME), and PEG-PDLLA nanovesicles were loaded with DOX (PEG-PDLLA-DOX), HMME (PEG-PDLLA-HMME), or the PEG-PDLLA nanovesicle alone as controls. The cytotoxicity of PEG-PDLLA-DOX-HMME, PEG-PDLLA-DOX, PEG-PDLLA-HMME, and PEG-PDLLA against HepG2 cells was measured, and the cellular reactive oxygen species, percentage of cells with mitochondrial membrane potential depolarization, and apoptotic rate following treatment were determined.

Results

Four nanovesicles (PEG-PDLLA-DOX-HMME, PEG-PDLLA-DOX, PEG-PDLLA-HMME, and PEG-PDLLA) were synthesized, and mean particle sizes were 175±18 nm, 154±3 nm, 196±2 nm, and 147±15 nm, respectively. PEG-PDLLA-DOX-HMME was more cytotoxic than PEG-PDLLA-DOX, PEG-PDLLA-HMME, and PEG-PDLLA. PEG-PDLLA-HMME-treated cells had the highest mean fluorescence intensity, followed by PEG-PDLLA-DOX-HMME-treated cells, whereas PEG-PDLLA-DOX- and PEG-PDLLA-treated cells had a similar fluorescence intensity. Mitochondrial membrane potential depolarization was observed in 54.2%, 59.4%, 13.8%, and 14.8% of the cells treated with PEG-PDLLA-DOX-HMME, PEG-PDLLA-HMME, PEG-PDLLA-DOX, and PEG-PDLLA, respectively. The apoptotic rate was significantly higher in PEG-PDLLA-DOX-HMME-treated cells compared with PEG-PDLLA-DOX- and PEG-PDLLA-HMME-treated cells.

Conclusion

The PEG-PDLLA nanovesicle, a drug delivery carrier, can be simultaneously loaded with two anticancer drugs (hydrophilic DOX and hydrophobic HMME). PEG-PDLLA-DOX-HMME cytotoxicity to HepG2 cells is significantly higher than the PEG-PDLLA nanovesicle loaded with DOX or HMME alone, and DOX and HMME have a synergistic effect against human hepatocellular carcinoma HepG2 cells.

Continuous transarterial infusion chemotherapy with gemcitabine and 5-Fluorouracil for advanced pancreatic carcinoma

PURPOSE

Pancreatic carcinoma is one of the most malignant tumors of the alimentary system, with relatively high incidence rates. The purpose of this study was to assess the efficacy and safety of two regimens for advanced pancreatic carcinoma: continuous transarterial infusion versus systemic venous chemotherapy with gemcitabine and 5-fluorouracil.

METHODS

Of the 48 patients with advanced pancreatic carcinoma receiving chemotherapy with gemcitabine and 5-fluorouracil, 24 received the selective transarterial infusion, and 24 the systemic chemotherapy. For the continuous transarterial infusion group (experimental group), all patients received gemcitabine 1000 mg/m2,given by 30-minute transarterial infusion, on day 1 of a 4-week cycle for 2 cycles, and a dose of 600 mg/ m2 5-fluorouracil was infused on days 1~5 of a 4-week cycle for 2 cycles. For the systemic venous group (control group), gemcitabine and 5-fluorouracil were infused through a peripheral vein, a dose of 1000 mg/m2 gemcitabine being administrated over 30 min on days 1 and 8 of a 4-week cycle for 2 cycles, and a dose of 600 mg/m2 5-fluorouracil was infused on days 1~5 of a 4-week cycle for 2 cycles. The effectiveness and safety were evaluated after 2 cycles according to WHO criteria.

RESULTS

The objective effective rate in transarterial group was 33.3% versus 25% in the systemic group, the difference not being significant (P=0.626). Clinical benefit rates(CBR) in the transarterial and systemic groups were 83.3% and 58.3%, respectively (P=0.014). The means and medians for survival time in transarterial group were higher than those of the systemic group (P<0.005). at the same time, the adverse effects did not significantly differ between the two groups (P>0.05).

CONCLUSION

Continuous transarterial infusion chemotherapy with gemcitabine and 5-fluorouracil could improve clinical benefit rate and survival time of patients with advanced pancreatic carcinoma, compared with systemic venous chemotherapy. Since adverse effects were limited in the transarterial group, the regimen of continuous transarterial infusion chemotherapy can be used more extensively in clinical practice. A CT and MRI conventional sequence can be used for efficacy evaluation after chemotherapy in pancreatic carcinoma.

[Dynamic contrast-enhanced MR imaging and digital subtraction angiography manifestation of hepatic focal nodular hyperplasia]

BACKGROUND & OBJECTIVE

Focal nodular hyperplasia (FNH) is a rare benign hepatic tumor and its imaging diagnosis remains difficult. This study was to analyze dynamic contrast-enhanced MR imaging and digital subtraction angiography (DSA) manifestation of FNH, and to improve the diagnostic accuracy of FNH.

METHODS

The MRI and DSA imaging data of 30 patients with FNH proved by pathology were reviewed. Conventional contrast-enhanced MRI was completed in 11 patients; dynamic contrast-enhanced MRI was completed in 15 patients. DSA was completed in 10 patients.

RESULTS

On dynamic contrast-enhanced MRI scan, 18 lesions in 15 patients showed obvious enhancement at arterial phase and prolonged enhancement at delayed phase. Central scars were found in 11 lesions, and showed enhancement since portal vein phase till delayed phase. The time-signal intensity curves of the 18 lesions were ascended rapidly at arterial phase, and descended slowly at portal vein phase and delayed phase. On DSA examination, 13 lesions in the ten patients showed dilated feeding arteries, and radiate feeding arterial branches were seen in eight lesions.

CONCLUSIONS

Dynamic contrast-enhanced MRI can fully show abnormal signal of the central scar of FNH. The time-signal intensity curve of FNH ascends rapidly and descends slowly. On DSA imaging, the feeding arteries of FNH spread radially. Dynamic contrast-enhanced MRI and DSA could improve the diagnostic accuracy of FNH.

[Efficacy of selective continuous transarterial infusion chemotherapy on advanced pancreatic cancer]

BACKGROUND & OBJECTIVE

Advanced pancreatic cancer is mainly treated by chemotherapy with poor prognosis. This study was designed to evaluate clinical efficacy and application of selective continuous transarterial infusion chemotherapy in treating patients with advanced pancreatic cancer.

METHODS

Twenty patients with advanced pancreatic cancer were treated by selective continuous transarterial infusion chemotherapy. The interventional treatment was performed with Seldinger technique,12 patients received percutaneous femoral artery cannulization and catheter retention, 8 received percutaneous left subclavian artery port-catheter system implantation. Chemotheraputic drugs were continuously infused when the catheter was selectively placed in turner feeding artery. Nine patients were treated with pirarubicin (THP)/adriamycin (ADM) plus hydroxycamptothecin (HCPT),and 5-fluorouracil (5-FU)/calcium folinate (CF) regimen,and 11 were treated with gemcitabine (GEM) plus carboplatin (CBP),and 5-FU/CF regimen. Treatment regimens were repeated every 4-6 weeks with each cycle of 4 days. Tumor response rate,clinical benefit response (CBR),and survival time were observed.

RESULTS

Objective response rate was 10% with 1 case of complete remission (CR), and 1 case of partial remission (PR), CBR was 70% (14/20), 6-,and 9-month survival rates were 58.8%,and 39.2%. Median survival time for all patients was 8.8 months. No complication related to cannulization was found.

CONCLUSION

Selective continuous transarterial infusion chemotherapy is safe,and has good efficacy in treating patients with advanced pancreatic cancer, it may prolong survival time of patients.