Objective:To explore the advantages of minimally invasive internal fixation assisted by an orthopedic robot in the treatment of tibial plateau fractures of Schatzker types Ⅱ and Ⅲ that can be indirectly reduced.Methods:A retrospective study was conducted of the 18 patients who had been treated for tibial plateau fractures of Schatzker types Ⅱ and Ⅲ at Department of Orthopaedics, The Fourth Hospital of Wuhan from December 2019 to December 2021. They were 12 males and 6 females with an age of (45.2±9.6) years. All fractures were closed. Of them, 6 were complicated with an avulsion fracture at the insertion point of the anterior cruciate ligament, 1 with tear of the medial collateral ligament, and 8 with tear of the lateral meniscus. All patients were treated with minimally invasive internal fixation using the "fence" screw technique after indirect reduction assisted by an orthopedic surgical robot. Those combined with avulsion fracture of the anterior cruciate ligament and meniscus tear underwent one-stage arthroscopic surgery, while those combined with tear of the medial collateral ligament underwent one-stage open repair. The fracture reduction was evaluated according to the Rasmussen radiological scoring system, and the knee joint function evaluated using the American Hospital for Special Surgery (HSS) scoring system.Results:All the 18 patients were fully followed up for (10.6±1.9) months. The X-ray films immediately after surgery showed good fracture reduction. The fractures healed after (11.3±1.2) weeks. At 6 months after surgery, the Rasmussen knee score was (16.8±1.0) points, giving 5 excellent and 13 good cases; the HSS score was (93.2±3.0) points, giving 17 excellent and 1 good cases. By the last follow-up, no serious complications occurred, such as common peroneal nerve injury, popliteal vascular injury, postoperative infection, or internal fixation failure.Conclusion:Since minimally invasive internal fixation assisted by an orthopedic robot can lead to fine clinical efficacy for tibial plateau fractures of Schatzker types Ⅱ and Ⅲ, this technique can be widely applied in clinical practice.

Objective:To trace and identify the source and the transmission vector of a nosocomial infection event caused by hypervirulent Acinetobacter baumannii. Methods:Nine strains of carbapenem-resistant Acinetobacter baumannii (CRAB) isolated from respiratory general ward and respiratory intensive care unit in Shenzhen People’s Hospital from July to August 2018 were collected. Environmental specimens such as ward environmental objects and medical staff’s hands were also collected. Vitek 2 was used for identification of bacterial species and drug susceptibility testing; Illuinam HiSeq 2500 platform, Staramr, Ridom SeqSphere+ were used for whole genome sequencing, drug resistance gene detection and multi-locus sequence typing (MLST); and IQ-Tree software, BEAST2 software package and SCOTTI software were used to construct phylogenetic tree and propagation path map. At the same time, the virulence of pathogenic bacteria was detected by mouse pneumonia model. Results:The 9 isolated CRAB strains were all ST2 type, all carried the carbapenem-resistant gene blaOXA-23, and the capsular types were KL49, KL3, KL77 and KL2, respectively. One of the CRAB strains isolated from removable ventilator screen was ST2 type and KL49 type capsule. Phylogenetic tree analysis showed that the environmental isolates were located in the same branch as 5 CRABs, and the transmission path map showed that these 5 CRABs were also located in the same transmission chain. Five strains of CRAB were involved in four lethal cases, and in vivo experiments in mice confirmed that the strains causing lethal infection had a hypervirulent phenotype. Conclusions:Highly virulent Acinetobacter baumannii can colonize the surface of mobile medical equipment, and sharing these equipment may lead to nosocomial spread of pathogens. The use of new propagation path analysis tools has certain reference significance for the investigation of propagation events.

Objective:To explore the capability of vascular endothelial growth factor receptor 2 (VEGFR2)/integrinα vβ 3 dual-targeted microbubbles in assessing the expression level of pro-angiogenic factors during renal cell carcinoma (RCC) growth. Methods:VEGFR2/integrinα vβ 3 dual-targeted microbubbles were prepared by using biotin-avidin linkage method. Twenty subcutaneous RCC xenografts in nude mice were established by subcutaneously injecting 786-O cells and then divided into 2 groups randomly. The targeted contrast-enhanced ultrasound (t-CEUS) examination was performed for all 10 mice in the first group when xenograft tumors were metered from 5 to 10 mm and >10 to 20 mm respectively. And the quantitative parameters of RCC on t-CEUS were longitudinally evaluated during tumor growth. The second group were divided into two subgroups according to xenograft tumors′ diameter, which was 5 to 10 mm and >10 to 20 mm respectively, and underwent t-CEUS examination. Quantitative analysis was performed for all t-CEUS images to obtain the targeted quantitative parameters, which including peak intensity (PI), area under the time-intensity curve (AUC), the differential tissue enhancement (dTE, presenting the difference in PI before (P 1) and after (P 2) the process of Flash). All xenograft tumors in the second group were harvested for immunohistochemical staining to observe the expression of VEGFR2, integrinα vβ 3 and CD31, and their differences in RCC with different tumor sizes. And the correlations between quantitative parameters and VEGFR2, integrinα vβ 3 and CD31 were analyzed. Results:The longitudinal comparison showed that there were statistically significant differences between AUC and dTE of RCC with different tumor sizes (all P<0.001). The larger the tumor size, the smaller the parameters were. According to the horizontal comparison, the expression levels of VEGFR2 and integrinα vβ 3 in larger RCCs were higher than those of RCCs with smaller size (both P<0.05), but there was no significant difference in CD31 expression between the two subgroups ( P=0.754). Both the targeted quantitative parameters (AUC anddTE ) and pro-angiogenic factors (VEGFR2 and integrinα vβ 3) were negatively correlated with tumor size ( rs=-0.83, -0.81, -0.70, -0.88; all P<0.05). Further more, there were good positive correlations between AUC and VEGFR2, integrinαvβ ( rs=0.76, 0.72; all P<0.05). There were good positive correlations between dTE and VEGFR2, integrinα vβ 3 ( rs=0.81, 0.70; all P<0.05). Additionally, the parameter PI was positively correlated with the expression of CD31 ( rs=0.70, P=0.025). Conclusions:The t-CEUS, mediated by VEGFR/integrinα vβ 3 dual-targeted microbubbles, allows noninvasive assessment of the expression levels of VEGFR2 and integrinα vβ 3 in RCCs, which decrease gradually with the increase of tumor size.

Objective:To evaluate the ability of vascular endothelial growth factor receptor 2(VEGFR2)/integrin α vβ 3 dual-targeted microubble (MBD) to target angiogenesis of renal cell carcinoma (RCC) in vivo. Methods:Non-targeted microbubble (MBN) USphere LA was employed as a template to prepare single- and dual-targeted microbubbles which could bind VEGFR2 and/or integrin α vβ 3 (MBV and MBI) by the biotin-avidin bridging method. A total of 40 RCC nude mice models were established by subcutaneously injecting 786-O cells.Twenty of the models were all injected with MBN, MBV, MBI and MBD in a random order, and the other 20 models were registered for antibody blocking assays. The results of ultrasound images were used for quantitative analyses, and the following quantitative parameters were obtained: intensity increment (a 1), peak halving speed (a 2), curve rising slope (a 3), perfusion time (t 0), time to peak (TTP), peak intensity (PI), mean transit time (MTT) and area under the curve (AUC) for the first three minutes, peak intensity at 10 s before (P 1) and after (P 2) ultrasound destruction, and the differences of tissue enhancement (dTE) between P 1 and P 2 (dTE=P 1-P 2). All the quantitative parameters of four contrast agents and the antibody blocking assays were compared.Besides, the immunohistochemical assays were performed to evaluate the expression of CD31, VEGFR2 and integrin α vβ 3 in tumor tissues. Results:The differences of parameters of a 1, a 3, t 0, TTP, PI and P 2 among four different microbubbles had no statistical significances (all P>0.05), and all parameters between the two single-targeted contrast agents were not statistically different (all P>0.05). The parameters of AUC, MTT, P 1 and dTE all showed a trend that dual-targeted bubbles > single-targeted bubbles > non-targeted bubbles (all P<0.05). On the contrary, the trend of dual-targeted bubbles < single-targeted bubbles < non-targeted bubbles (all P<0.05) was observed for a 2. In the antibody blocking experiment, a 2 was faster after the antibody injection ( P<0.001), while AUC, MTT, P 1 and dTE were all lower than those before the antibody injection ( P<0.001), and the other parameters were not statistically different before and after the antibody injection (all P>0.05). Immunohistochemical analyses confirmed the high expression of CD31, VEGFR2 and integrin β 3 in tumor tissues. Conclusions:The VEGFR2 and integrin α vβ 3 dual-targeted microbubble has a good potential to target the angiogenesis of human RCC in vivo.

Objective:To explore the diagnostic performance of ultrasound attenuation imaging (ATI) in grading the degree of hepatic steatosis in metabolic dysfunction-associated fatty liver disease (MAFLD).Methods:The liver gray-scale ultrasound and ATI examinations were performed on 212 subjects who were treated in Zhongshan Hospital Affiliated to Fudan University from August 2020 to March 2021. The attenuation coefficient(AC) values among different degrees of hepatic steatosis were analyzed and the diagnostic performance of ATI was evaluated. Relationships between AC values and clinical characteristics were assessed by Pearson′s correlation analysis.Results:The AC values for normal liver, mild, moderate and severe fatty liver were (0.56±0.05)dB·cm -1·MHz -1, (0.68±0.09)dB·cm -1·MHz -1, (0.82±0.09)dB·cm -1·MHz -1, (0.94±0.09)dB·cm -1·MHz -1, respectively. There were significant differences in AC values among different hepatic steatosis divisions( P<0.008). There was highly significant correlation between AC values and the degree of hepatic steatosis( r=0.860, P<0.01), moderate correlation between AC values and BMI( r=0.425, P<0.01), weak correlation between AC values and HDL-C( r=-0.237, P=0.029), no correlations between AC values and age, TC, TG, LDL-C ( r=0.083, 0.055, 0.133, -0.039, all P>0.05) .The areas under the receiver operating characteristics curve of ATI for mild fatty liver and above, moderate fatty liver and above, severe fatty liver and above were 0.958, 0.962, 0.918; the sensitivity were 90.1%, 95.8%, 94.9%, the specificity were 96.1%, 87.1%, 73.9%, and the cut-off values were 0.666 dB·cm -1·MHz -1, 0.719 dB·cm -1·MHz -1, 0.803 dB·cm -1·MHz -1, respectively. Conclusions:ATI is a reliable and convenient method for evaluating the degree of hepatic steatosis in MAFLD.

Objective:To investigate the contrast-enhanced ultrasound (CEUS) features of inflammatory hepatocellular adenoma (I-HCA).Methods:The contrast-enhanced ultrasound features I-HCA of 28 cases from April 2009 to November 2019 in Zhongshan Hospital, Fudan University were retrospectively analyzed, including arterial phase enhancement pattern, the homogeneity of enhancement, subcapsular enhancement, and the internal perfusion defect. All I-HCA lesions were divided into >5 cm group( n=9) and ≤5 cm group( n=19), the CEUS features between the two groups were compared. Results:All I-HCA lesions were hyper-enhanced in the arterial phase, among which 39.3% (11/28) showed diffuse filling, 39.3%(11/28) showed centripetal filling, and 21.4%(6/28) showed centrifugal filling pattern. Twenty-five percent (7/28) of I-HCAs showed heterogeneous enhancement, 10.7% (3/28) revealed unenhanced areas within the lesions. Subcapsular vessels were observed in 67.7 (21/31) of I-HCA lesions. Heterogeneous enhancement and unenhanced areas were more frequently detected in lesions >5 cm ( P=0.020, 0.026, respectively), while there was no difference in the enhancement pattern and subcapsular vessels between the two groups ( P>0.05). Inportal venous phase, 42.9%(12/28) of I-HCAs showed hypo-enhancement, and 57.1%(16/28) of lesions showed washout in late phase. According to "hyper-enhancement in arterial phase, sustained hyper- or iso-enhancement in portal venous and late phase" by CEUS, the diagnostic accuracy of benign lesion was 42.9%(12/28). According to any of hyper-enhancement pattern in arterial phase, subcapsular vascular enhancement, and sustained hyper- or iso-enhancement in portal venous and late phase, the diagnostic accuracy of I-HCA was 71.4% (20/28). Conclusions:CEUS is valuable in the diagnosis of inflammatory hepatocellular adenoma.

Objective:To investigate the value of contrast-enhanced ultrasonography (CEUS) in detecting minute renal cell carcinoma (MRCC) smaller than 15 mm (by ultrasonic measurement) and the strategy to improve its detection rate.Methods:Fifty-three pathologically confirmed MRCCs by surgery from November 2007 to October 2019 at Zhongshan Hospital of Fudan University were enrolled in this retrospectively study. All of them underwent both conventional ultrasound and CEUS examinations. The clinical and imaging data were collected and analyzed. Common features, such as tumor size, location, echogenicity, morphology, border, and blood flow signals were observed on conventional ultrasound. On CEUS, the presence of enhancement, wash in and wash out pattern, perfusion uniformity within the lesions were observed.Results:Post-operative pathology confirmed 48 clear cell carcinomas, 4 papillary carcinomas, and 1 chromophobe cell carcinoma. On conventional ultrasound, 12/53 lesions showed no protrusion out of the kidney, and 41/53 cases slightly protruded out of the kidney. There was considerable difficulty in the detection of ten lesions, which was achieved with the guidance of CT/MRI, due to their dorsal location of the kidney. On conventional ultrasound, solid, hyper-echoic, color flow signal with varying degrees were the main features of MRCC.The boundary could be well- or ill-defined, and cystic changes existed in part of cases. On CEUS, most MRCCs showed simultaneous enhancement in cortical phase, iso- to hyper-enhancement at peak, and rapid washout in parenchymal phase. The comparisons of imaging features demonstrated that the characteristics were significantly different between conventional ultrasound and CEUS with regard to boundaries, blood supply, and perfusion uniformity (χ 2=12.425, 20.247, 7.185; all P<0.01). Conclusions:CEUS can significantly improve the detection rate of MRCC, which is superior to conventional ultrasound.

Objective:To explore the value of contrast-enhanced ultrasound(CEUS) in distinguishing of renal oncocytoma(RO) and chromophobe renal cell carcinoma(chRCC).Methods:The ultrasonic image features of 49 ROs and 72 chRCCs between October 2007 and January 2020 were retrospectively analyzed, all lesions underwent ultrasonic examination (including 19 ROs and 70 chRCCs with CEUS imaging) and were pathologically approved in our institution. The statistically significant parameters from univariate analyses were then entered for further multivariable Logistic regression. The value of each ultrasonic imaging feature in differentiating RO and chRCC was evaluated.Results:According to the univariate analyses, all imaging features on conventional ultrasound were not statistically different between RO and chRCC (all P>0.05), while the characteristics of tumor wash-in/out pattern, enhancement degree and homogeneity at peak time and pseudocapsule around tumor were significantly different (all P<0.05). After multivariable analyses, tumor wash-in and wash-out pattern were excluded for tumor differentiation ( P>0.05), and the parameters of enhancement degree or homogeneity at peak time and pseudocapsule around tumor were still significantly different between tumor types (all P<0.05, odd ratio was 8.683, 6.667 and 18.774 respectively). The overall sensitivity, specificity and accuracy of these three parameters in diagnosing RO was 68.4%, 91.4% and 86.5%, respectively. Conclusions:CEUS can provide some useful information for the differentiation of RO and chRCC.

Objective:To study clinical pathological characteristics, immunohistochemical, molecular genetical changes and prognosis in pediatric eosinophilic solid and cystic renal cell carcinoma (ESC RCC) with TSC2 gene mutations.Methods:The tissue samples were collected from two pediatric ESC RCC patients between 2017 and 2018. The tissues were subjected to histological examination and immunohistochemistry using EnVision system. The TFE3, TFEB gene rearrangements were tested using FISH and molecular genetic study. The paraffin sections were used for DNA extraction, PCR amplification and NGS sequencing.Results:The two patients with ESC RCC were both male, aged at 9 years and 8 months, and 13 years, respectively. The tumors were from the right kidney, 5 cm and 7 cm in size, respectively, with solid and cystic changes in cross section, and grey-reddish or grey-whitish fish meat appearance. Microscopic observation revealed the tumors had fibrous capsules, which were infiltrated by the tumor cells. The tumor cells were diffusely distributed, round-shaped, or polygon-shaped, and had voluminous cytoplasm, eosinophilic cytoplasm, various sizes of vacuoles and clear cell-like appearance. There were papillary structures in some areas, with visible fiber septa. The nuclei were round and vesicular, with multi-nucleated cells and megakaryocytes. The mitoses were not seen. A few cystic structures were visible in different sizes, and capsule walls were covered with a single layer of spike-like tumor cells. Thick-walled blood vessels were seen in the stroma, with focal lymphocytic infiltration, eosinophilic necrosis, calcifications and cholesterol crystals. Immunohistochemistry of the tumor cells was positive for PAX8 (diffuse), CK20 (focal), CKpan (focal), CK10 (1 focal, 1 diffuse), INI1, vimentin, CD68, and Ki-67 (5%~10%); the tumor cells were negative for HMB45, S-100, Melan A, p53, desmin, TFE3, CK7, CK19, EMA, CD56, CgA, Syn, CD30, CD117, WT1 and SMA. Molecular genetic study showed that TFE3 and TFEB gene rearrangements were not detected by FISH. NGS sequencing showed TSC2 p.Lys574Ter (0.198) was found in patient one and TSC2 p.Arg406Ter (0.355) in patient two.Conclusions:ESC RCC in children is a rare disease, and can be misdiagnosed easily. It has unique pathological characteristics, and immunohistochemical, molecular and genetic changes. The prognosis is relatively good.

Objective: To investigate the value of contrast-enhanced ultrasound(CEUS) in differential diagnosis of complex renal cysts and clear renal cell carcinoma with cystic change(CRCCC). Methods: The ultrasonographic datas of 82 lesions in 82 patients with complicated renal cysts or CRCCC confirmed by pathology were analyzed. The characteristics of conventional ultrasound and CEUS were observed and evaluated. The lesions were graded according to Bosniak classification criteria. Results: Pathological examination showed that 36 cases were complicated renal cysts and 46 cases were CRCCC. Routine ultrasound showed there were 9 cases (25.0%) with cystic masses and 27 cases (75.0%) with solid and cystic masses in complex renal cysts, of which 14 cases (38.9%) could detect color flow signals. In CRCCC, 2 cases (4.3%) were with cystic masses and 44 cases (95.7%) were with solid and cystic masses, of which 33 cases (75.0%) could detect color flow signals. CEUS showed that only 18 cases (50.0%) of the complex renal cysts showed enhancement of cystic wall or septum, with equal or low enhancement at the peak, 9 cases (50.0%) accompanied by decrease of renal cortex, 35 cases (97.2%) had thin and regular cystic wall, no enhancement of cystic wall in all lesions, and 33 cases (91.7%) had septal thickness less than 1 mm. Forty-five cases (97.8%) of CRCCC showed enhancement of cystic wall or septum, 40 cases (88.9%) showed equal or high enhancement at peak, 30 cases (66.7%) were faster than the decrease of renal cortex, 37 cases (80.4%) showed uneven thickness of cystic wall, 24 cases (52.2%) showed enhancement of cystic wall nodules, and 28 cases (60.9%) showed uneven thickness of septum. After CEUS, 33 cases (91.7%) of complex renal cysts were classified as grade Ⅰ and Ⅱ, while 42 cases (91.3%) of CRCCC were classified as grade Ⅲ and Ⅳ. Conclusions The CEUS manifestations of complex renal cysts are different from those of CRCCC. The application of Bosniak criteria in CEUS is helpful for the differential diagnosis of complex renal cysts and CRCCC.