Shielding Performance of Electromagnetic Shielding Fabric Implanted with "Split-Ring Resonator".

The electromagnetic shielding (EMS) fabric is an important electromagnetic protection product, which is widely applied in various fields. The improvement of its shielding effectiveness (SE) has always been the focus of research. This article proposes to implant a metamaterial structure of a "split-ring resonator (SRR)" in the EMS fabrics, so that the fabric not only maintains the porous and lightweight characteristics, but also obtains the SE improvement. With the help of the invisible embroidery technology, stainless-steel filaments were used to implant hexagonal SRRs inside the fabric. The effectiveness and influencing factors of the SRR implantation were described by testing the SE of the fabric and analyzing the experimental results. It was concluded that the SRR implantation inside the fabric can effectively improve the SE of the fabric. For the stainless-steel EMS fabric, the increase amplitude of the SE reached between 6 dB and 15 dB in most frequency bands. The overall SE of the fabric showed a decrease trend with the reduction of the outer diameter of the SRR. The decrease trend was sometimes fast and sometimes slow. The decreasing amplitudes were different in various frequency ranges. The number of embroidery threads had a certain effect on the SE of the fabric. When other parameters remained unchanged, the increase of the diameter of the embroidery thread resulted in the increase of the SE of the fabric. However, the overall improvement was not significant. Finally, this article also points out that other influencing factors of the SRR need to be explored, and the failure phenomenon may occur under certain situations. The proposed method has the advantages of the simple process, convenient design, no pore formation, SE improvement retaining the original porous characteristics of the fabric. This paper provides a new idea for the design, production, and development of new EMS fabrics.

Nomograms to predict survival outcomes after microwave ablation in elderly patients (>65 years old) with early-stage hepatocellular carcinoma.

Objectives: To develop and validate the nomograms to predict survival outcomes after microwave ablation (MWA) in elderly patients(>65 years old) with early-stage hepatocellular carcinoma (EHCC).Methods: This retrospective study was approved by the institutional review board. A total of 265 EHCC patients (76 females, 189 males; average age 71.4 years ± 5.4 [standard deviation]) with 345 nodules subsequently underwent MWA from April 2006 to October 2019. Baseline characteristics were collected to identify the risk factors for the determination of survival outcomes after MWA. The nomograms were based on prognostic factors for overall survival (OS) and recurrence-free survival (RFS) from the multivariate Cox proportional hazards model and validated in external cohorts from another two institutions (n = 130). The nomograms were assessed for their predictive accuracy using Harrell's concordance index (C-index).Results: After a median follow-up time of 28.6 months, 29.8% (79/265) of the patients died, and 54.3% (144/265) of the patients experienced recurrence in the training set. The OS nomogram was developed based on the hepatitis B virus (HBV) presence, α-fetoprotein (AFP), and albumin, with a C-index of 0.757 (95% confidence interval [CI]: 0.645, 0.789).The scores of the nomogram ranged from 0 to 24. The RFS nomogram was developed based on tumor number, abutting major vessels and platelets, with a C-index of 0.733 (CI: 0.672, 0.774). The likelihood of 3- and 5-year OS and RFS were consistent between clinical observations and nomogram predictions in external cohorts.Conclusions: The nomogram models can be useful in determining the risk of OS and RFS in elderly patients with EHCC after MWA, which can guide individual patient management.Key pointsMWA is an effective and feasible treatment for elderly patients with EHCC and can improve survival outcomes.A calibrated and objective nomogram model for the prediction of survival outcomes in elderly patients (>65 years old) may guide patient selection and MWA treatment.Older age was not deemed to be a risk factor for survival outcomes when the elderly patients with EHCC underwent MWA.

Clinical efficacy and prognostic factors of CT-guided 125I brachytherapy for the palliative treatment of retroperitoneal metastatic lymph nodes.

BACKGROUND: Due to the unique anatomical location of retroperitoneal metastatic lymph nodes, current treatment options are limited. This study was designed to explore the clinical efficacy and prognostic factors of CT-guided 125I brachytherapy for the treatment of retroperitoneal metastatic lymph nodes. METHODS: We retrospectively evaluated 92 patients received 125I brachytherapy for retroperitoneal metastatic lymph nodes. A layered Cox proportional hazards model was established to filter out the independent factors affecting local tumor progression-free survival (LTPFS). RESULTS: The median LTPFS was 8 months. Metastatic lymph node with uniform density (p-0.009), clear boundaries (p-0.011), regular morphology (P < 0.001), and < 3 organs at risk of metastasis (p-0.020) were associated with better LTPFS. Necrotic lymph nodes (p < 0.001), fusion (p-0.003), and invasion of vessels visible on images (p < 0.001) were associated with poor LTPFS. Puncture path through abdominal wall or paravertebral approach were also associated with better LTPFS than a hepatic approach (P < 0.05). A maximum diameter ≤ 3 cm (P-0.031) or 3-5 cm (P-0.018) were also associated with significantly better LTPFS than a maximum diameter ≥ 5 cm. The Cox proportional hazards model suggested that lymph nodes invaded the large vessels visible on images, maximum diameter and puncture path were independent risk factors for LTPFS. CONCLUSION: CT-guided 125I brachytherapy is an optional palliative treatment modality for retroperitoneal metastatic lymph nodes, which can provide high local control without severe complications. Better preoperative planning, intraoperative implementation, better choice of puncture path, and selection of appropriate tumor size are important factors that can improve the clinical efficacy of 125I brachytherapy for retroperitoneal metastatic lymph nodes.

Computed tomography-guided radiofrequency ablation combined with transarterial embolization assisted by a three-dimensional visualization ablation planning system for hepatocellular carcinoma in challenging locations: a preliminary study.

OBJECTIVE: To assess the clinical efficacy and safety of computed tomography-guided radiofrequency ablation(CT-RFA) combined with transarterial embolization(TAE) assisted by a three-dimensional visualization ablation planning system(3DVAPS) for hepatocellular carcinoma(HCC) in challenging locations. METHODS: Data from 62 treatment-naive patients with hepatocellular carcinoma(HCC), with 83 lesions in challenging locations, and who met the Milan criteria and underwent CT-RFA between June 2013 and June 2016 were reviewed. Patients were divided into one of two groups according to different treatment modalities: study group (TAE combined with RFA assisted by 3DVAPS [n = 32]); and control (RFA only [n = 30]). Oncological outcomes included ablation-related complications, local tumor progression (LTP), and overall survival (OS). Univariate and multivariate Cox proportional hazards regression analyses were performed to assess risk factors associated with LTP and OS. RESULTS: HCC lesions (mean size, 1.9 ± 1.0 mm in diameter) abutting the gastrointestinal tract (n = 25), heart and diaphragm (n = 21), major vessels (n = 13), and gallbladder (n = 3) were treated. A significant difference was detected in LTP between the two groups (P = 0.034), with no significant difference in OS between the two groups (P = 0.193). There were no severe complications related to ablation. Univariate analysis revealed that sex (P = 0.046) and child-turcotte-pugh (CTP) grade (P<0.001) were risk factors for OS, whereas CTP grade and treatment method (P<0.001) were risk factors for LTP. Multivariate analysis revealed that CTP grade B (P = 0.005) was independently associated with poor OS, and RFA alone (P<0.001) was independently associated with poor LTP. CONCLUSION: CT-RFA combined with TAE assisted by a 3DVAPS provided ideal clinical efficiency for HCC in challenging locations and was a highly safe treatment modality.

Adjuvant cytokine-induced killer cells with minimally invasive therapies augmented therapeutic efficacy of unresectable hepatocellular carcinoma.

OBJECTIVE: To investigate the safety and therapeutic efficacy of adjuvant cytokine-induced killer (CIK) cells to minimally invasive therapies in unresectable hepatocellular carcinoma (u-HCC). MATERIALS AND METHODS: Hundred patients diagnosed with having u-HCC in our department from January 1, 2001, to July 31, 2018, were recruited. Forty-three patients received microwave ablation (MWA) and transcatheter arterial chemoembolization (TACE) together with autologous CIK cell treatment (TACE + MWA + CIK group), whereas 57 patients received TACE and MWA only (TACE + MWA group). Postprocedural complications and cumulative therapeutic effects were assessed in all patients. The disease control rate, median survival time (MST), and cumulative survival rate were compared between the cohorts using the Kaplan-Meier method and unpaired Student's t-tests. RESULTS: The overall response (complete response [CR] + partial response [PR]) rate was 74.42% (32/43) and 77.19% (44/57) for TACE + MWA + CIK and TACE + MWA groups, respectively (P = 0.243). Those of the TACE + MWA + CIK group had better rates of disease control (CR + PR + stable disease) in contrast to the TACE + MWA group (87.72% vs. 79.07%, respectively) but this failed to achieve statistical significance (P = 0.748). Based on the Kaplan-Meier survival graphs, those of the TACE + MWA + CIK groups possessed markedly increased overall survival (41 months vs. 24 months, P = 0.002) and progression-free survival (17 months vs. 10 months, P = 0.023) rates in compared to the TACE + MWA group. Survival rates were raised also TACE + MWA + CIK group than in TACE + MWA group (P = 0.002), with a MST of 6.13 ± 0.83 months and 11.61 ± 1.59 months in the TACE + MWA + CIK and TACE + MWA groups, respectively. Patients in the TACE + MWA + CIK group were not reported to have any severe complications. CONCLUSION: CIK cell immunotherapy as an adjuvant to TACE and MWA enhanced long-term prognosis and improved quality of life in patients with u-HCC. This regimen may be recommended as a novel treatment regime in u-HCC patients.

Computed tomography-guided radiofrequency ablation of the retained iodized oil after simultaneous combination with transarterial embolization in small recurrent or residual hepatocellular carcinoma.

OBJECTIVE: To assess the clinical efficacy and safety of transarterial embolization (TAE) in simultaneous combination with computed tomography (CT)-guided radiofrequency ablation (RFA) for recurrent or residual hepatocellular carcinoma (HCC), and to determine the risk factors influencing local tumor progression following this procedure. METHODS: One hundred eighteen patients with recurrent or residual HCC (tumor size, 10-30 â€‹mm) underwent RFA. During the 19-month follow-up, 59 patients received RFA only (RFA group), and the remaining 59 received RFA immediately after TAE (TAE â€‹+ â€‹RFA group). All patients were followed up to observe the short-term therapeutic effects and complications. The cumulative local tumor progression rates in both groups were calculated using unpaired Student's t tests and the Kaplan-Meier method. RESULTS: The rate of major complications was 5.08% in the TAE â€‹+ â€‹RFA group and 3.39% in the RFA group. The overall response rate was 96.61% in the TAE â€‹+ â€‹RFA group and 79.66% in the RFA group (P â€‹= â€‹0.008). The disease control rate was significantly higher in the TAE â€‹+ â€‹RFA group than in the RFA group (94.92% vs. 79.66%, P â€‹= â€‹0.024). The median time to local tumor progression was 4.8 months in the RFA group and 9.6 months in the TAE â€‹+ â€‹RFA group. The cumulative local tumor progression rate at 1 year was 10.60% in the RFA group and 23.60% in the TAE â€‹+ â€‹RFA group (P â€‹= â€‹0.016). CONCLUSION: TAE in simultaneous combination with CT-guided RFA was effective and safe against recurrent or residual HCC. Local tumor progression can be minimized by the complete ablation of targeted iodized oil deposits after simultaneous TAE.

Combination Therapy after TACE for Hepatocellular Carcinoma with Macroscopic Vascular Invasion: Stereotactic Body Radiotherapy versus Sorafenib.

Stereotactic body radiotherapy (SBRT) has shown promising results in the control of macroscopic vascular invasion in patients with hepatocellular carcinoma (HCC); however, its efficacy in comparison to sorafenib when combined with transarterial chemoembolization (TACE) remains to be determined. Between 2009 and 2017, 77 HCC patients with macroscopic vascular invasion receiving TACE⁻SBRT or TACE⁻sorafenib combination therapies were enrolled. The best treatment responses, overall survival (OS), and progression-free survival (PFS) of the two treatment arms were compared. Of the patients enrolled, 26 patients (33.8%) received TACE⁻SBRT treatment, and 51 (66.2%) received TACE⁻sorafenib treatment. The patients in the TACE⁻SBRT group were more frequently classified as elder in age (p = 0.012), having recurrent disease (p = 0.026), and showing lower rates of multiple hepatic lesions (p = 0.005) than patients in TACE⁻sorafenib group. After propensity score matching (PSM), 26 pairs of well-matched HCC patients were selected; patients in the TACE⁻SBRT group showed better overall response rates in trend compared to those in the TACE⁻sorafenib group. The hazard ratio (HR) of OS to PFS for the TACE⁻SBRT approach and the TACE⁻sorafenib approach was 0.36 (95% CI, 0.17⁻0.75; p = 0.007) and 0.35 (95% CI, 0.20⁻0.62; p < 0.001), respectively. For HCC patients with macrovascular invasion, TACE plus SBRT could provide improved OS and PFS compared to TACE⁻sorafenib therapy.