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ObjectiveTo explore the Therapeutic effect of synchronous Integrated intensity modulated radiotherapy combined with chemotherapy in stage IIIc of Cervical CancerMethodsA total of 58 patients with stage IIIC cervical cancer (KPS ≥ 80) were analyzed in this study. They were admitted to our hospital between August 2017 and August 2022. Synchronous integrated boost intensity-modulated radiotherapy (SIB-IMRT) and sequential boost intensity-modulated radiotherapy (LCB-IMRT) were used to treat pelvic and/or para-aortic metastatic lymph nodes, with 30 cases in the SIB group and 28 cases in the LCB group. Comparison of short-term and long-term efficacy. Comparison of recurrence and metastasis rates, radiation dose to organs at risk and incidence of adverse drug reactions.Result30 patients were treated with simultaneous integrated boost intensity-modulated radiotherapy (SIB-IMRT), and 28 patients were treated with sequential boost intensity-modulated radiotherapy (LCB-IMRT). At the completion of radiotherapy and 3 months after radiotherapy, there was no significant difference in clinical efficacy observed between the two treatment groups. The median overall survival (OS), progression-free survival (PFS), and disease-free survival (DMR) in the SIB-IMRT group were significantly higher compared to the LCB-IMRT group. The SIB-IMRT group demonstrated significantly lower rates compared to the LCB-IMRT group. Furthermore, within 3 years and 5 years, the rates of lymph node recurrence, cervical and vaginal local recurrence, and distant metastasis within the radiotherapy field were significantly lower in the SIB-IMRT group compared to the LCB-IMRT group. There were no significant differences observed between the two groups in terms of the maximum dose to the small intestine (Dmax), dose received by 2cc of the small intestine (D2cc), maximum dose to the rectum (Dmax), and dose received by 1cc of the bladder (D1cc). The incidence of bone marrow toxicity in the SIB-IMRT group was significantly lower compared to the LCB-IMRT group. Moreover, the occurrence of grade III and IV bone marrow toxicity was also significantly lower in the SIB-IMRT group compared to the LCB-IMRT group.ConclusionThe study has concluded that there is no significant differences in in terms of bladder associated adverse events and gastrointestinal toxicity in both Simultaneous Integrated Boost Intensity-Modulated Radiotherapy and Layered Conical Beam Intensity-Modulated Radiation Therapy.

A novel type of tubular structure with negative Poisson's ratio based on gyroid-type triply periodic minimal surfaces (TPMSs) is proposed in this study. This work is an attempt to design auxetic tubular structures based on TPMS. A series of auxetic tubular structures were designed and then fabricated using laser power bed fusion. Compressive behaviours of the fabricated auxetic tubular structures were investigated using experimental and numerical methods. To obtain optimal designs of tubular structures with controllable auxetic properties, the influence of several parameters were investigated comprehensively. Subsequently, several graded auxetic tubular structures were designed based on the parametric analysis and studied numerically. The mechanical properties of the tubular structures could be controlled effectively using the proposed approach. The proposed method can be used for guiding the design and optimisation of auxetic tubular structures, showing excellent potential for various applications such as biomedical devices, vehicle crashworthiness, and protective engineering.

Triply periodic minimal surfaces (TPMS) - based porous structures have been universally adopted for mimicking the properties of bone scaffolds due to their interconnected geometries with smooth surfaces and controllable pores. To further increase the versatility and controllability, an enhanced porous scaffold based on TPMS is proposed. The enhanced pores with different sizes are designed onto three types of TPMS-based scaffolds and then additively manufactured through laser powder bed fusion (LPBF). To investigate the manufacturability, various approaches are used and the results confirm that morphological features of printed samples are identical to the designed ones. As for mechanical properties, the results from the compression tests show that the elastic modulus and compressive strength of enhanced porous scaffolds are 2.0 GPa to 5.1 GPa and 86.7 MPa to 264.2 MPa respectively, which are all in the range of human bones. In terms of permeability, both experiments and simulation indicate that the designed scaffolds have 40%−150% improvement compared to scaffolds without enhanced pores. The biocompatibility of the scaffolds is further verified by in vitro studies. The results demonstrate the suitability of the proposed enhanced porous scaffolds for bone implants, and it will facilitate the design of more effective porous materials.

Objective. To explore the impact of radiation dose on preoperative neoadjuvant chemoradiotherapy effects for patients with locally advanced squamous cell esophageal carcinoma (LASCEC) with long-term follow-up data. Methods. The patients with LASCEC received either low dose radiotherapy (50.4Gy/23f/1.8Gy) or a high dose (64.8Gy/25f/1.8Gy) followed by neoadjuvant chemotherapy preoperatively were included in this study. To balance potential bias, 1 : 1 propensity score matching (PSM) with a caliper of 0.1 was used. The two groups were compared in terms of radical resection, post-radiation adverse event rates, perioperative mortality, postoperative adverse event rates, overall survival (OS), local recurrence rate, and distant metastatic rate. Results. Forty-two patients were enrolled in this study, with 21 patients in each group after PSM. There was no difference in baseline characteristics between the two groups (all p >0.05). The rates of radical resection (71.4% vs 57.1%, P =0.334), perioperative mortality (9.5% vs 4.8%, P =0.549), and postoperative adverse event rates (76.2% vs 90.5%, P =0.410) did not differ significantly between the two groups. The 5-year OS rate was statistically higher in the group with a high dose (66.7% vs. 28.6%, P =0.013). Meanwhile, the local recurrence rate was statistically lower in the high dose group (14.3% vs 47.6%, P =0.019 for 3 years; 33.3% vs 66.6%, P =0.031 for 5 years). Moreover, the 3-year distant metastasis rate was statistically lower in the group with a high dose (9.5% vs 38.1%, P = 0.03). Conclusion. Patients with LASCEC may benefit from preoperative neoadjuvant chemoradiotherapy with a high radiation dosage (64.8Gy/25f/1.8Gy).

Triply periodic minimal surfaces (TPMS) became an effective method to design porous scaffolds in recent years due to their superior mechanical and other engineering properties. Since the advent of additive manufacturing (AM), different TPMS-based scaffolds are designed and fabricated for a wide range of applications. In this study, Schwarz Primitive triply periodic minimal surface (P-TPMS) is adopted to design a novel porous scaffold according to the distribution of the scaffold stress under a fixed load with optimized thickness to tune both the mechanical and biological properties. The designed scaffolds are then additively manufactured through selective laser melting (SLM). The micro-features of the scaffolds are studied through scanning electron microscopy (SEM) and micro-computed tomography (CT) images, and the results confirm that morphological features of printed samples are identical to the designed ones. Afterwards, the quasi-static uniaxial compression tests are carried out to observe the stress–strain curves and the deformation behavior. The results indicate that the mechanical properties of the porous scaffolds with optimized thickness were significantly improved. Since the mass transport capability is important for the transport of nutrients within the bone scaffolds, computational fluid dynamics (CFD) are used to calculate the permeability under laminar flow conditions. The results reveal that the scaffolds with optimized structures possess lower permeability due to the rougher inner surface. In summary, the proposed method is effective to tailor both the mechanical properties and permeability, and thus offers a means for the selection and design of porous scaffolds in biomedical fields.