OBJECTIVES: We present a new low-dose CT reconstruction method using sub-pixel and anisotropic diffusion. METHODS: The sub-pixel intensity values and their second-order differences were obtained using linear interpolation techniques, and the new gradient information was then embedded into an anisotropic diffusion process, which was introduced into a penalty-weighted least squares model to reduce the noise in low-dose CT projection data. The high-quality CT image was finally reconstructed using the classical filtered back-projection (FBP) algorithm from the estimated data. RESULTS: In the Shepp-Logan phantom experiments, the structural similarity (SSIM) index of the CT image reconstructed by the proposed algorithm, as compared with FBP, PWLS-Gibbs and PWLS-TV algorithms, was increased by 28.13%, 5.49%, and 0.91%, the feature similarity (FSIM) index was increased by 21.08%, 1.78%, and 1.36%, and the root mean square error (RMSE) was reduced by 69.59%, 18.96%, and 3.90%, respectively. In the digital XCAT phantom experiments, the SSIM index of the CT image reconstructed by the proposed algorithm, as compared with FBP, PWLS-Gibbs and PWLS-TV algorithms, was increased by 14.24%, 1.43% and 7.89%, the FSIM index was increased by 9.61%, 1.78% and 5.66%, and the RMSE was reduced by 26.88%, 9.41% and 18.39%, respectively. In clinical experiments, the SSIM index of the image reconstructed using the proposed algorithm was increased by 19.24%, 15.63% and 3.68%, the FSIM index was increased by 4.30%, 2.92% and 0.43%, and the RMSE was reduced by 44.60%, 36.84% and 15.22% in comparison with FBP, PWLS-Gibbs and PWLS-TV algorithms, respectively. CONCLUSIONS The proposed method can effectively reduce the noises and artifacts while maintaining the structural details in low-dose CT images.
Tomography, X-Ray Computed/methods* ; Algorithms ; Phantoms, Imaging ; Anisotropy ; Image Processing, Computer-Assisted/methods* ; Humans ; Radiation Dosage

Objective To observe area of coagulation necrosis after microwave ablation(MWA)of rabbit liver showed on contrast-enhanced ultrasound(CEUS)in comparison with pathological findings.Methods Twenty-five healthy male experimental rabbits were equally randomly divided into L0,M0,H0,M7 and M14 groups.MWA was achieved with different power and time,and then CEUS and pathological examinations were performed,respectively.Four target areas of rabbit liver were ablated under 20 W for 1 min in L0 group,under 30 W for 1 min in M0 group and under 30 W for 3 min in H0 group,and the ablated areas were observed on the same day after MWA,while 2 target areas of rabbit liver were ablated under 30 W for 1 min in M7 and M14 groups,and the ablated areas were observed 7 days and 14 days after MWA,respectively.The ablated foci and ablated foci+edema band(inflammatory reaction band,IRB)showed on CEUS and pathology were compared,and their differences and changes with time going were analyzed.Results On the day of ablation,the extent of ablation foci,ablation foci+IRB as well as IRB in L0,M0 and H0 groups showed on CEUS were all larger than pathological findings under light microscopy(all P＜0.05),and the difference value of the length of the ablation foci between 2 methods increased sequentially among group L0,M0 and H0(all adjusted P＜0.05).Seven days after ablation,the area of ablation foci measured with CEUS in M 7 group was slightly larger than that measured with pathology(adjusted P=0.045),but no significant difference of the length nor the short diameter was found(both adjusted P＞0.05).Fourteen days after ablation,no significant difference of the length,the short diameter nor the area of ablation foci was detected between 2 methods in M14 group(all adjusted P＞0.05).The length,short diameter and area of ablation foci in M0 group measured with CEUS or pathology were all smaller than those in M 7 and M14 groups(all adjusted P＜0.05),while no significant difference was found between the latter 2 groups(all adjusted P＞0.05).Conclusion On the day of MWA of rabbit liver with different power and time settings,the areas of ablation foci,ablation foci+IRB and IRB showed on CEUS were larger than pathological findings.The range of ablation foci showed on CEUS 7 days after ablation was basically in line with pathology,indicating that CUES should be reexamined 7 days after ablation to evaluate the actual extent of coagulation and necrosis of ablation foci.

Objective To observe the impact of cold circulation liquid temperature on ablation focus morphology of microwave ablation(MWA)for in vitro porcine liver tissue.Methods Twenty in vitro fresh porcine liver blocks were randomly divided into ice water circulation group(group A)and normal temperature circulation group(group B),respectively.Ten target ablations in each subgroups in group A and group B,i.e.A1 and B1(50 W,1 min),A2 and B2(50 W,5 min),A3 and B3(60 W,1 min),A4 and B4(60 W,5 min),A5 and B5(70 W,1 min)as well as A6 and B6(70 W,5 min)subgroups were performed using different ablation power(50,60,70 W)and ablation time(1,5 min),respectively.Then the morphology indexes of ablation foci,including longitudinal diameter(LD),transverse diameter(TD),roundness index(RI)and volume(V)were compared between subgroups in group A and B,also among subgroups within group A and B.Results Under the same ablation power and time,LD of ablation foci in subgroups of group A were all smaller than those of group B(all P＜0.05).Significant differences of RI of ablation foci were found between A1 and B1,A2 and B2,A4 and B4,A5 and B5 as well as A6 and B6 subgroups(all P＜0.05),but not between A3 and B3 subgroups(P＞0.05).However,the main effect of cold circulation liquid temperature on ablation focus TD(F=1.125)nor V(F=3.332)was not significant(both P≥0.05).Under the same cold circulation liquid temperature,significant differences of the morphology indexes of ablation foci were detected between A1 and A2,A3 and A4 as well as A5 and A6 subgroups,also between corresponding subgroups in group B(all P＜0.05).Conclusion During MWA for in vitro porcine liver tissue under constant ablation power and time,taken ice water as the cold circulation liquid was benefit to ablation focus shaped spherically.With the extension of ablation time,the larger the ablation focus,the higher the RI.

Objective:To investigate the safety and effectiveness of robot-assisted total knee arthroplasty (TKA).Methods:From August 2021 to March 2022, the data of 69 patients who received robot-assisted TKA for inflammatory disease of knee in 6 hospitals were collected, including 24 males and 45 females, aged 52±6 years (range, 46-72 years), including 53 cases of knee osteoarthritis,10 cases of rheumatoid arthritis, and 6 cases of traumatic arthritis. Imaging data examination of patients was completed according to the multicenter specification. Preoperatively, the patient's CT data were extracted before surgery and a personalized prosthesis positioning plan was designed by the robotic system to determine the prosthesis size, lower limb force lines, and femoral and tibial osteotomy volumes; intraoperatively, the osteotomy template was robotically controlled to complete the osteotomy according to the prosthesis positioning plan, and the intraoperative osteotomy volumes were measured to verify the accuracy of the robot-assisted TKA osteotomy with the preoperative planning. Postoperatively, the lateral angle of the distal femur, the medial angle of the proximal tibia and the hip-knee-ankle angle were measured in the coronal plane according to radiographs; the postoperative outcome was evaluated 3 months after operation, using the American Knee Society score (KSS), including the KSS knee score and functional score.Results:The operative time was 97.3±2.3 min (range, 80-110 min) and the amount of bleeding was 320.0±6.2 ml (range, 300-350 ml) in 69 patients. Three months after operation, the mean range of motion of knee joint was increased from 82.2°±1.1° before surgery to 119.7°±0.8° after surgery ( t=27.65, P<0.001), and the line of force of lower limb was improved from 160.9°±0.5° before surgery to 178.0°±0.2° after surgery ( t=32.03, P<0.001). KSS-knee score increased from 54.8±0.7 points before operation to 85.0±0.5 points after operation, and KSS-functional score increased from 56.5±0.7 points before operation to 85.9±0.4 points after operation, the difference was statistically significant ( t=35.45, 36.58, P<0.001). The proportion of patients with intraoperative femoral and tibial osteotomies within 2 mm osteotomy error compared with preoperative planning was 97% for the lateral tibial plateau, 100% for the medial tibial plateau, 100% for the lateral distal femur, 99% for the medial distal femur, 93% for the lateral posterior femoral condyle, and 100% for the medial posterior femoral condyle; The proportion of patients with postoperative anteroposterior X-ray measurement angle error within 3° was: 100.0% for the distal lateral femoral angle, 100.0% for the proximal medial tibial angle, and 100% for the hip-knee-ankle angle. No complications occurred in all patients except for one case in which fat liquefaction occurred in the postoperative wound. Conclusion:Robot-assisted TKA is a safe and effective surgical method for the treatment of inflammatory disease of knee with accurate prosthesis installation and good postoperative recovery of lower limb alignment.

Objective: To observe the association between puberty development and thyroid function among school-aged girls in Minhang District of Shanghai, in order to explore the effect of puberty development on thyroid function. Methods: The study was based on a cohort of adolescent girls recruited in iodine-suitable areas of Minhang District, and the baseline and follow-up survey have been carried out from January to March 2019. The method of phased cluster sampling was used to select one junior high school in the east, south, north and middle of Minhang District, Shanghai, respectively. Finally, 464 new junior high school girls were included in the Cohort study for physical examination, and girls were followed up from January to March 2021. The Puberty Development Scale (PDS) was used to assess the stage of puberty. Serum thyroid stimulating hormone (TSH), free triiodothyronine (FT3), and free thyroxine (FT4) were determined for each participant. Thyroid homeostasis structure parameters (THSPs) was calculated. Changes of Thyroid hormones at baseline and follow-up were compared by Wilcoxon signed rank sum test. Multiple linear regression analyses were used to evaluate the associations of thyroid hormones (THs) and THSPs changes with pubertal develepment. Results: Serum TSH levels of female studentds decreased significantly, while their FT3 and FT4 levels increased significantly during the study period ( Z=-10.53, -4.71, -12.46, P <0.01). In multiple linear regression analysis after adjustment for co-variables (including baseline age, change of BMI and waist circumference), FT4 and thyroid feedback quantile-based index (TFQI) in the higher puberty category scores changes (△PCS) group were further reduced compared with those in the low △PCS group ( β =-0.66, -0.55 ). Compared to the late puberty at baseline and follow-up (BLFL) group, FT4 and TFQI showed higher decline in the pre-puberty at baseline and late puberty at follow-up (BPFL) group with the pre-puberty at baseline and end of puberty at follow-up (BPFT) group ( β =-0.55, -0.44)( P <0.05). There were no association of △TSH, △FT3, △FT4/FT3 and TSH index changes (△TSHI) with △PCS or the puberty pattern. Conclusion Serum TSH decreases while serum FT3 and FT4 increase among girls during puberty. Both the initial stage and the velocity of pubertal development are related to thyroid hormone fluctuations.

Fear memories are temporarily suppressed after repeated retrieval, a phenomenon known as memory extinction.How to reduce or even eliminate fear memory is the key to the treatment of fear related diseases such as post-traumatic stress disorder(PTSD). A single extinction training based on Pavlov's fear regulation task could only inhibit the expression of conditioned fear memory traces, but it could not eliminate the acquired conditioned fear memory. However, according to the reconsolidation theory based on memory, the retrieval-extinction paradigm has a more lasting effect on the erasure and rewriting of fear memory, and can effectively prevent the return of fear memory. Studies have shown that extraction-regression is closely related to a variety of neurotransmitter receptors such as glutamate receptor(GluR), dopamine receptor(DAR), L-type voltage-gated calcium channels(LVGCs) and cannabinoid. Moreover, its effect is closely related with factors such as retrieval-extinction memory stage. At present, most of the researches on extracted boundary conditions only stay at the level of behavior, with little understanding and exploration on the level of molecular mechanism. From the perspective of molecular neurobiology, with different stages of memory and different types of receptors and molecular mechanisms, this research reviewed the mechanisms of retrieval-extinction in recent years.It provided valuable signaling pathways, molecular targets and research directions for the treatment of fear-related diseases such as PTSD.

Nonalcoholic fatty liver disease (NAFLD) and colorectal adenomatous polyps are closely associated with the various components of metabolic syndrome. This article summarizes the recent studies on the association between NAFLD and colorectal adenomatous polyps, and the results show that NAFLD is associated with an increased risk of colorectal adenomatous polyps, while related mechanism remains unclear, which may be associated with insulin resistance, chronic inflammatory response, adipokines, and intestinal flora disturbance.

Objective To successfully get the full PCR alleles of the Insertion/Deletion marker rs10644346 in which a SNP-binding exists at the 3'end region of the primer.Methods Based on the AS-PCR,a common forward primer and two reverse primers with allele-specific oligonucleotides at the last second 3'end instead of the terminus were tentatively designed for typing 150 unrelated individuals and 10 father-mother--child trios from Htnan province in South-central China.Simultaneously,9 samples were typed with all the above three primers (the two primer sets which consist of the common forward primer and one of the reverse primers).Results PCR amplicons were well detected in the 150 unrelated individuals after being typed with the three primers,and the amplified fragments of parental and filial generations among 10 father-mother-child trios conformed to Mendel's principles.Allele missing was found in the two-primer group.Conclusion The primers designed by locating the specific nucleotide at the last second 3'end rather than terminal position were demonstrated also effective in getting specific alleles if perfect mismatch and PCR conditions are guaranteed,and the design strategy can provide an optional reference to rescue markers of SNP-binding primers for forensic practice.

Objective The expression of chemokine C-X-C motif ligand 13 (CXCL13) within liver in primary biliary cholangitis (PBC) patients is significantly increased, but its origin and mechanism is not clear yet.The study aimed to investigate the expression of CXCL13 in the liver of mice through establishing a mouse model of PBC.Methods C57BL/6 mice were randomly divided into experiment group (n=20) control group(n=10).The mice in the experimental group were intraperitoneally injected with polyriboinosinic polyribocytidylic acid (Poly I:C) while the mice in control group were injected with PBS of the same volume.The level of serum AMA was quantified by ELISA and intrahepatic inflammatory cells were assessed by HE staining.Kupffer cells, liver sinusoidal endothelial cells, and infiltrating lymphocytes in the liver of mice were collected by in situ perfusion enzyme digestion and magnetic bead separation methods.The transcriptional level of intrahepatic CXCL13 in liver tissues and cell subpopulations were detected by qPCR.Results The serum AMA titers of the mice in experiment group increased gradually with the prolonging of modeling time and the positive rates at the 4th, 8th, and 12th week after the first injection of Poly I:C were 5.9%, 52.9% and 76.5% respectively.While the serum AMA titers of the mice in control group were at a lower level through the modeling process, with only 2 mice presenting a little higher level above positive cutoff value at the 12th week.The results of HE staining in liver tissues of both groups showed that there were a great amount of intensely infiltrating inflammatory cells in the mice of experimental group while no inflammatory cell infiltration were found in the mice of control group.The separation purity of Kupffer cells and liver sinusoidal endothelial cells in the mice of experiment group tested by flow cytometry were 76%-80%, 68%-72% respectively.Compared with the CXCL13 mRNA level in Kupffer cells [2.34(0.22-8.64)], the expression levels in liver sinusoidal endothelial cells and infiltrating lymphocytes declined[0.27(0.03-1.64), 0.05(0-0.22), P<0.05].Conclusion The chemokine CXCL13 is predominantly produced by Kupffer cells in the liver of PBC mice established by Poly I:C injection.

OBJECTIVETo study the effects of RhoA down-regulation by RNA interference on the invasion of tongue carcinoma Tca8113 and SCC-4.

METHODSDetermination of the human RhoA sequence as well as the design and constructionof a short specific small interfering RNAs (siRNA) were performed. The siRNA of RhoA gene was transfected into humantongue squamous cell carcinoma Tca8113 and SCC-4 cells line by Lipofectamine 2000. Quantitative real-time polymerasechain reaction was used to examine the mRNA expressionlevels of RhoA. Protein expressions of mRNA, galectin-3,and matrix metalloproteinase (MMP)-9 were evaluated byWestern blot. Transwell invasion assay was performed toassess the invasion ability of tongue carcinoma.

RESULTSRhoA expressions in Tca8113 and SCC-4 cells were reducedsignificantly after transfection of RhoA-siRNA. Protein levels f galectin-3 and MVP-9 were also down-regulated significantly. Invasion ability was inhibited as well.

CONCLUSIONRhoA-siRNA can effectively inhibit RhoA expression in Tca8113 and SCC-4 cells. The invasion ability of tongue carcinoma cells decreased with down-regulation of the protein expressions of galectin-3 and MMP-9, indicating that RhoA-siRNA can inhibit invasion of tongue carcinoma. Results show that RhoA may play an important role in the processes of invasion and metastasis of tongue carcinoma.

Carcinoma, Squamous Cell ; genetics ; metabolism ; pathology ; Cell Line, Tumor ; Down-Regulation ; Galectin 3 ; metabolism ; Gene Silencing ; Humans ; Matrix Metalloproteinase 9 ; metabolism ; RNA Interference ; RNA, Messenger ; metabolism ; RNA, Small Interfering ; genetics ; Tongue Neoplasms ; genetics ; metabolism ; pathology ; Transfection