Objective:To design a novel model for experiments on in vitro irradiation with radioactive seeds using a treatment planning system (TPS) and 3D printing technology and to preliminarily validate the design scientific rigor of the model via experiments on isodose brachytherapy (BT) and external beam radiotherapy (EBRT) on glioma cells in mice. Methods:The TPS was employed to design the model′s shape and calculate the number and positions of radioactive seeds, and 3D printing technology was utilized to fabricate the experimental model. The GL261 cell line was selected for in vitro irradiation experiments, with the mice divided into the control, EBRT, and BT groups. Mice in the EBRT and BT groups were treated with EBRT and BT, respectively, at doses of 2, 4, and 6 Gy. Then, changes in their cell viability, proliferation, and the level of intracellular reactive oxygen species (ROS) were assessed. Results:The model for in vitro irradiation with radioactive seeds was successfully designed and fabricated. The single photon emission computed tomography (SPECT) verified a uniform radioactive distribution within the model, with no significant cold spots. The BT and EBRT groups displayed decreased cell viability with an increase in the radiation dose. Compared to the EBRT group, the BT group exhibited significantly reduced cell viability (51.33% vs. 22.00%, t = 10.94, P < 0.05) and clone counts (172.67 ± 13.11 vs. 53.67 ± 10.22, t = 8.73, P < 0.05), but a significantly increased level of ROS (102.52 ± 6.87 vs. 144.81 ± 6.01, t = -5.26, P < 0.05) at a dose of 6 Gy. Conclusions:An effective model of in vitro irradiation with radioactive seeds is designed based on TPS and 3D printing technology. This provides an experimental model tool and target for research on the BT and EBRT mechanisms.

Objective:To employ single-photon emission computed tomography (SPECT)/CT for isodose assignment in 125I brachytherapy, assess the correlation between photon counts and dose values, and develop a clinical γ-ray visualization model for 125I brachytherapy. Methods:125I radioactive seeds were filled into a self-made 3D printed stereotactic template to build a stereotactic model. The model was scanned by SPECT/CT for photon counts at 0.5, 1.0, 1.5, 2.0 cm from the outermost peripheral seeds, and the corresponding dose values were measured using the Treatment Planning System (TPS). The fitting curve for the photon counts and the dose values was plotted using SPSS 27.0 software. Results:The photon counts of γ rays at distances of 0.5, 1.0, 1.5, and 2.0 cm from the peripheral particles were 7 603.57±1 806.35, 4 018.26±1 315.72, 2 074.04±791.53, and 1 080.34±424.79, respectively, showing a significant difference ( F=743.72, P<0.01). The dose values (in Gy) in the TPS at distances of 0.5, 1.0, 1.5, and 2.0 cm from the peripheral particles were 208.05±37.57, 125.43±17.74, 86.76±17.67, and 61.55±14.39, respectively, which were significantly different ( F=930.46, P<0.01). The photon counts were linearly correlated with the dose values ( y=0.02 x+ 46.45, R2=81.2%, P<0.01). Conclusions:SPECT/CT-based γ-ray photon count detection can be used to assign doses for 125I brachytherapy, enabling the visualization of γ rays in 125I brachytherapy. This approach has a distinct advantage over TPS, laying the foundation for the establishment of an alternative system to TPS.

Objective:To design a novel model for experiments on in vitro irradiation with radioactive seeds using a treatment planning system (TPS) and 3D printing technology and to preliminarily validate the design scientific rigor of the model via experiments on isodose brachytherapy (BT) and external beam radiotherapy (EBRT) on glioma cells in mice. Methods:The TPS was employed to design the model′s shape and calculate the number and positions of radioactive seeds, and 3D printing technology was utilized to fabricate the experimental model. The GL261 cell line was selected for in vitro irradiation experiments, with the mice divided into the control, EBRT, and BT groups. Mice in the EBRT and BT groups were treated with EBRT and BT, respectively, at doses of 2, 4, and 6 Gy. Then, changes in their cell viability, proliferation, and the level of intracellular reactive oxygen species (ROS) were assessed. Results:The model for in vitro irradiation with radioactive seeds was successfully designed and fabricated. The single photon emission computed tomography (SPECT) verified a uniform radioactive distribution within the model, with no significant cold spots. The BT and EBRT groups displayed decreased cell viability with an increase in the radiation dose. Compared to the EBRT group, the BT group exhibited significantly reduced cell viability (51.33% vs. 22.00%, t = 10.94, P < 0.05) and clone counts (172.67 ± 13.11 vs. 53.67 ± 10.22, t = 8.73, P < 0.05), but a significantly increased level of ROS (102.52 ± 6.87 vs. 144.81 ± 6.01, t = -5.26, P < 0.05) at a dose of 6 Gy. Conclusions:An effective model of in vitro irradiation with radioactive seeds is designed based on TPS and 3D printing technology. This provides an experimental model tool and target for research on the BT and EBRT mechanisms.

Objective:To employ single-photon emission computed tomography (SPECT)/CT for isodose assignment in 125I brachytherapy, assess the correlation between photon counts and dose values, and develop a clinical γ-ray visualization model for 125I brachytherapy. Methods:125I radioactive seeds were filled into a self-made 3D printed stereotactic template to build a stereotactic model. The model was scanned by SPECT/CT for photon counts at 0.5, 1.0, 1.5, 2.0 cm from the outermost peripheral seeds, and the corresponding dose values were measured using the Treatment Planning System (TPS). The fitting curve for the photon counts and the dose values was plotted using SPSS 27.0 software. Results:The photon counts of γ rays at distances of 0.5, 1.0, 1.5, and 2.0 cm from the peripheral particles were 7 603.57±1 806.35, 4 018.26±1 315.72, 2 074.04±791.53, and 1 080.34±424.79, respectively, showing a significant difference ( F=743.72, P<0.01). The dose values (in Gy) in the TPS at distances of 0.5, 1.0, 1.5, and 2.0 cm from the peripheral particles were 208.05±37.57, 125.43±17.74, 86.76±17.67, and 61.55±14.39, respectively, which were significantly different ( F=930.46, P<0.01). The photon counts were linearly correlated with the dose values ( y=0.02 x+ 46.45, R2=81.2%, P<0.01). Conclusions:SPECT/CT-based γ-ray photon count detection can be used to assign doses for 125I brachytherapy, enabling the visualization of γ rays in 125I brachytherapy. This approach has a distinct advantage over TPS, laying the foundation for the establishment of an alternative system to TPS.

Objective Toinvestigatetheshort-termefficacyoftranscatheterarterialchemoembolization(TACE)combinedwith microwaveablation (MWA;TACE-MWA)inthetreatmentofmultinodularhepatocellularcarcinoma (HCC).Methods 58patients withmultinodularHCCtreatedintheinterventionalmedicinecenterfromJanuary2015toJanuary2017wereincludedingradeAor B.34cases(groupA)receivedTACEand24cases(groupB)underwentTACE-MWAtherapy.Theshort-termefficacywasevaluatedbyfollow-upandanalysisofthetimetoprogression (TTP),localrecurrencerate,newlesionrate,andpostoperativecomplicationsinboth groups.Results TheTTPinthetwogroupswas38-240 (106.2±63.1)daysand90-630 (328.5±178.8)daysrespectively.The incidenceofpostoperativecomplicationsintwogroupswas2.9% (1/34)and4.2% (1/24)respectivelyI.ngroupA,thelocalrecurrenceratewas 52.9% (18/34)andthenewfocusratewas76% (26/34);inthegroupB,thelocalrecurrenceratewas8.3% (2/24)andthenewfocusratewas 66.7% (16/24).Thedifferenceoflocalrecurrenceratebetweenthetwogroupswasstatisticallysignificant(P<0.05),whiletheincidenceofnew lesionwasnotsignificantlydifferent (P>0.05).Conclusion TACE-MWAissafeandeffectiveinthetreatmentofmultinodular HCC.ComparingwithtraditionalTACEtreatment,TACE-MWAcansignificantlyimprovedTTPandlocalcontrolrate.

BACKGROUND: Scholars have been trying to create a microenvironment similar to the human body, which can induce the directional differentiation of mesenchymal stem cells from human bone marrow, placenta and umbilical cord blood. OBJECTIVE: To compare the neuronal differentiation of human bone marrow mesenchymal stem cells, human placental mesenchymal stem cells and human umbilical cord blood mesenchymal stem cells induced by co-culture with nerve cells. METHODS: Human bone marrow mesenchymal stem cells, human placental mesenchymal stem cells and human umbilical cord blood mesenchymal stem cells cultured in vitro were co-cultured with nerve cells using the Transwell system. The morphological changes of three kinds of cells in the co-culture system were detected. After co-culture for4-5 days, immunofluorescence staining was used to measure the expression of neuron-specific enolase in cells. Mesenchymal stem cells only cultured in low glucose DMEM medium were used as controls. RESULTS AND CONCLUSION: These three kinds of mesenchymal stem cells were extended, and interconnected processes were detective. The positive expression of neuron-specific enolase was highest in the human umbilical cord blood mesenchymal stem cells followed by human placental mesenchymal stem cells and human bone marrow mesenchymal stem cells in order. In the control group, none of the three kinds of mesenchymal stem cells have neuronal morphology, and the expression of neuron specific enolase was negative for the immunofluorescence staining. To conclude, microenvironment provided by nerve cells can induce these three kinds of mesenchymal stem cells todifferentiate into neurons.

A new sonographic pattern of fetal hydrocephalus-midline-waved sign, and its mechanism were reported in this paper. When the abdominal wall of the pregnant woman was percussed by hand during ultrasound examination, the wave of midline echo was observed on sonoimage. The diagnosis of hydro-cephalus was made by this sign in all 12 fetuses, and confirmed by autopsy. No dilatation of the cerebral ventricle was observed in 5 out of 12 fetuses. It would be difficult to make the diagnosis of hy-drocephalus would previous diagnostic criteria be used. This sign is negative in normal fetuses, therefore-this finding has the practical value in the early and differential diagnoses of hydrocephalus.