Fumarate Restrains Alveolar Bone Restoration via Regulating H3K9 Methylation.

Nonresolving inflammation causes irreversible damage to periodontal ligament stem cells (PDLSCs) and impedes alveolar bone restoration. The impaired tissue regeneration ability of stem cells is associated with abnormal mitochondrial metabolism. However, the impact of specific metabolic alterations on the differentiation process of PDLSCs remains to be understood. In this study, we found that inflammation altered the metabolic flux of the tricarboxylic acid cycle and induced the accumulation of fumarate through metabolic testing and metabolic flux analysis. Transcriptome sequencing revealed the potential of fumarate in modulating epigenetics. Specifically, histone methylation typically suppresses the expression of genes related to osteogenesis. Fumarate was found to impede the osteogenic differentiation of PDLSCs that exhibited high levels of H3K9me3. Various techniques, including assay for transposase-accessible chromatin with high-throughput sequencing, chromatin immunoprecipitation sequencing, and RNA sequencing, were used to identify the target genes regulated by H3K9me3. Mechanistically, accumulated fumarate inhibited lysine-specific demethylase 4B (KDM4B) activity and increased H3K9 methylation, thus silencing asporin gene transcription. Preventing fumarate from binding to the histone demethylase KDM4B with α-ketoglutarate effectively restored the impaired osteogenic capacity of PDLSCs and improved alveolar bone recovery. Collectively, our research has revealed the significant impact of accumulated fumarate on the regulation of osteogenesis in stem cells, suggesting that inhibiting fumarate production could be a viable therapeutic approach for treating periodontal diseases.

Acromegaly presented with acne vulgaris: a retrospective study with 123 cases.

BACKGROUND: Acne vulgaris is a prevalent skin condition. We have found that some acromegaly patients have acne. However, no study has examined the relationship between acromegaly and acne. OBJECTIVE: To explore prevalence and correlation of adult acne in patients with acromegaly. METHODS: For this cross-sectional study, we collected questionnaires, clinical information, and laboratory test results of acromegaly patients from January 2022 to December 2022 at Huashan Hospital. Of the 133 questionnaires returned, 123 had valid responses. RESULTS: Of the 123 patients with acromegaly enrolled in this study, 54.5% had adult acne. No statistically significant difference was found in prevalence between male and female patients. 61.2% of adult acne patients reported late-onset acne. Late-onset acne patients first developed acne years before acromegaly diagnosis (mean of 5.6 years for male and 4.5 years for female patients). Some acne patients have received traditional anti-acne treatment. Moreover, 31% of the patients reported no improvement, and only 3.5% of patients claimed complete resolution of acne after treatment. Before acromegaly treatment, the prevalence of adult acne was 51.2%, with mild acne accounting for 73.0%, moderate acne accounting for 23.8%, and severe acne accounting for 3.2%. After acromegaly treatment, the prevalence of adult acne was significantly decreased to 37.4% (P = 0.007). An overall decrease in acne severity was noted, with 93.5%, 6.5%, and 0% having mild, moderate, and severe acne, respectively. A total of 83.6% of the patients had self-assessed acne remission, and 33.3% of the patients reported complete acne resolution. However, 9.0% of patients reported that their condition had worsened after acromegaly treatment. After treatment, GH, IGF-1, IGF-1 index, insulin levels, and HOMA-IR decreased significantly in all patients with acromegaly (P < 0.05). Acne remission correlated positively with IGF-1 levels, but not with GH levels. The relationship between acromegaly and acne remains to be elucidated. CONCLUSIONS: Our findings provide preliminary evidence of the high prevalence of adult acne in acromegaly patients, and a high rate of late-onset acne as well. Traditional anti-acne treatments are less effective. Acne could be considerably relieved by treating acromegaly. Acne remission positively correlated with IGF-1 decline as well, which revealed the correlation between acne and IGF-1.

[The role of intravoxel incoherent motion diffusion-weighted imaging in distinguishing diabetic nephropathy from non-diabetic renal disease in diabetic patients].

Objective: To investigate the intravoxel incoherent motion (IVIM) diffusion-weighted imaging (DWI) in the differential diagnosis of diabetic nephropathy (DN) and non-diabetic renal disease (NDRD) among patients with type 2 diabetes mellitus (T2DM). Methods: A diagnostic test. In this prospective study, patients with T2DM who underwent both IVIM-DWI and renal biopsy at the First Medical Center of Chinese PLA General Hospital between October 2017 and September 2021 were consecutively enrolled. IVIM-DWI parameters including perfusion fraction (f), pure diffusion coefficient (D), and pseudo-diffusion coefficient (D*) were measured in the renal cortex, medulla, and parenchyma. Patients were divided into the DN group and NDRD group based on the renal biopsy results. IVIM-DWI parameters, clinical information, and diabetes-related biochemical indicators between the two groups were compared using Student's t-test or Mann-Whitney U test. The correlation of IVIM-DWI parameters with diabetic nephropathy histological scores were analyzed using Spearman's correlation analyzes. The diagnostic efficiency of IVIM-DWI parameters for distinguishing between DN and NDRD were assessed using the receiver operating characteristic (ROC) curves. Results: A total of 27 DN patients and 23 NDRD patients were included in this study. The DN group comprised 19 male and 8 female patients, with an average age of 52±9 years. The NDRD group comprised 16 male and 7 female patients, with an average age of 49±10 years. The DN group had a higher D* value in the renal cortex and a lower f value in the renal medulla than the NDRD group (9.84×10-3 mm2/s vs. 7.35×10-3 mm2/s, Z=-3.65; 41.01% vs. 46.74%, Z=-2.29; all P<0.05). The renal medulla D* value was negatively correlated with DN grades, interstitial lesion score, and interstitial fibrosis and tubular atrophy (IFTA) score (r=-0.571, -0.409, -0.409; all P<0.05) while the renal cortex f value was positively correlated with vascular sclerosis score (r=0.413, P=0.032). The renal cortex D* value had the highest area under the curve (AUC) for discriminating between the DN and NDRD groups (AUC=0.802, sensitivity 91.3%, specificity 55.6%). Conclusion: IVIM-derived renal cortex D* value can be used non-invasively to differentiate DN from NDRD in patients with T2DM that can potentially facilitate individualized treatment planning for diabetic patients.

[Diagnostic value of multiparametric MRI-based models in the assessment of extra-prostatic extension of prostate cancer].

Objective: To evaluate the diagnostic value of multiparametric magnetic resonance imaging (mpMRI) based models in the assessment of extra-prostatic extension (EPE) of prostate cancer. Methods: This retrospective study included 168 consecutive men with prostate cancers [aged 48 to 82 (66.6±6.8) years] who underwent radical prostatectomy and preoperative mpMRI examinations at the First Medical Center of the PLA General Hospital from January 2021 to February 2022. According to European Society of Urogenital Radiology (ESUR) score, EPE grade and mEPE score, all cases were independently evaluated by two radiologists, with disagreement reviewed by a senior radiologist as the final result. The diagnostic performance of each MRI-based model for pathologic EPE prediction was assessed using receiver operating characteristic curve (ROC), and the differences between the corresponding area under the curve (AUC) were compared using the DeLong test. The weighted Kappa test was used to evaluate the inter-reader agreement of each MRI-based model. Results: A total of 62 (36.9%) prostate cancer patients had pathologic confirmed EPE after radical prostatectomy. The AUC of ESUR score, EPE grade and mEPE score for predicting pathologic EPE were 0.836 (95%CI: 0.771-0.888), 0.834 (95%CI: 0.769-0.887) and 0.785 (95%CI: 0.715-0.844), respectively. The AUC of ESUR score and EPE grade were both superior to that of mEPE score with significant differences (all P<0.05), while there was no significant difference between the ESUR score and EPE grade models (P=0.900). EPE grading and mEPE score had good inter-reader consistency, with weighted Kappa values of 0.65 (95%CI: 0.56-0.74) and 0.74 (95%CI: 0.64-0.84), respectively. The inter-reader consistency of ESUR score was moderate, and the weighted Kappa value was 0.52 (95%CI: 0.40-0.63). Conclusion: All MRI-based models showed good preoperative diagnostic value in predicting EPE, among which the EPE grade resulted in more reliable performance with substantial inter-reader agreement.

[Value of clear cell likelihood score in differentiation between renal oncocytoma and clear cell renal cell carcinoma].

Objective: To evaluate the value of clear cell likelihood score (ccLS) in identifying renal oncocytoma (RO) and clear cell renal cell carcinoma (ccRCC). Methods: Retrospective data of pathologically confirmed 43 RO patients [24 men and 19 women, aged 22-77 (54±14) years] between February 2008 and September 2021 and 43 ccRCC patients [30 men and 13 women, aged 29-78 (56±12) years] between May and July 2021 were consecutively included in the department of radiology, Chinese PLA General Hospital. Two radiologists used ccLS to assess each case independently, and disagreements were resolved by consensus. The ability of ccLS to identify RO and ccRCC was examined by the receiver operating characteristic (ROC) curve which identified the best optimal diagnostic cut-off values, sensitivity, specificity, accuracy, positive predictive value, and negative predictive value. Results: The mean tumor diameter was 3.8 cm in RO patients and 3.7 cm in ccRCC patients. Central scar and segmental enhancement inversion (SEI) were more frequently observed in the RO group compared to the ccRCC group [53.5% (23∶43) versus 11.6% (5∶43) and 41.9% (18∶43) versus 7.0% (3∶43), respectively], with statistical differences (P<0.001). The ccLS scores in the RO group ranged from 1 to 4, while 79.0% of the cases were 3. The ccLS scores in the ccRCC group ranged from 2 to 5, while 72% of the cases were 4. The scores of the two groups were statistically different (P<0.001). The ccLS showed the best performance when the threshold was 4 according to the ROC curve. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of ccLS for distinguishing RO from ccRCC were 83.7%, 90.7%, 87.2%, 90.0%, and 84.8%, respectively, and the area under the ROC curve value was 0.879. Conclusion: The ccLS has credible sensitivity and specificity in differentiating renal oncocytoma from clear cell carcinoma, which may be helpful for the preoperative diagnosis.

[Promote the application of dual-energy CT in abdominal malignant tumors].

With the progress of medical imaging technology and the accumulation of experience, dual-energy CT has moved from simple scientific research to clinical application. In the imaging of abdominal tumors, dual-energy CT has obvious advantages over conventional CT in improving the diagnostic performance, reflecting the pathological characteristics of malignant tumors and evaluating the therapeutic effect. This paper briefly describes the classification of dual-energy CT, the current research status of this technology in abdominal malignant tumors, and puts forward the challenges and application traps faced by dual-energy CT technology, in order to promote the clinical generalization and application of this technology.

[Application value of diffusion-weighted imaging signal pattern in the qualitative diagnosis of renal lesions with T(2)WI hypointensity].

Objective: To analyze the diagnostic value of diffusion-weighted imaging (DWI) signal pattern in renal lesions with T(2)WI hypointensity. Methods: Retrospective analysis was performed on DWI imaging datasets of 135 renal lesions with hypointentsity on T(2)WI confirmed by surgery, biopsy, or follow-up in the First Medical Center of Chinese PLA General Hospital from February 2016 to February 2017.One hundred and thirty-five renal lesions,43 benign lesions(age from 28 to 70 years,mean age was 43.5 years, male 18 lesions and female 25 lesions) and 92 malignant lesions (age from 17 to 86 years, mean age was 54.1 years, male 62 lesions and female 30 lesions). DWI signal pattern was classified into six categories: homogeneously high signal, homogeneously low signal, heterogeneously high signal, high halo signal, high halo and nodular signal, and high nodular signal. The agreement between two observers were tested using kappa statistic. The statistical difference between DWI signal characteristics in benign and malignant lesions was analyzed with Chi-Square test. Diagnostic efficacy in differentiation of benign and malignant renal lesions using DWI signal pattern were calculated. Results: One hundred and thirty-five lesions were detected in 135 cases with T(2)WI hypointensity. There were 43 benign lesions and 92 malignant lesions. The agreement between two observers was very good (kappa value=0.878 6). In renal T(2)WI hypointensity lesions, the proportion of DWI homogeneous high signal, homogeneous low signal, heterogeneous high signal, high halo signal, high halo and nodular signal, high nodular signal was 4.7% (2/43), 25.6% (11/43), 30.2% (13/43), 18.6% (8/43), 11.6% (5/43), 9.3% (4/43), respectively. The proportion of malignant lesions was 10.9% (10/92), 0 (0/92), 17.4% (16/92), 13.0% (12/92), 56.5% (52/92) and 2.2% (2/92), respectively. The difference of high halo and nodules signal and homogeneous low signal was statistically significant (all P<0.01). The sensitivity, specificity, positive prediction value (PPV) and negative prediction value (NPV) of high halo and nodular signal for malignancy were 56.5% (52/92), 88.4%(38/43), 91.2% (52/57) and 48.7%(38/78), respectively and homogeneous low signal for benign lesions were 25.6% (11/43), 100.0% (92/92), 100.0% (11/11) and 74.2% (92/124), respectively. Conclusions: DWI signal features may facilitated the accurate diagnosis of renal lesions with T(2)WI hypointensity. Malignant lesions exhibit a higher propensity with high halo and nodular signal on DWI while benign lesions with homogeneous low signal.

[Magnetic resonance imaging findings of hypovascular clear cell renal cell carcinoma].

Objective: To analyze MRI findings of hypovascular clear cell renal cell carcinoma. Methods: The clinical data and MRI findings of patients with hypovascular clear cell RCC confirmed by pathology from February 2016 to March 2017 were retrospectively analyzed in General Hospital of Chinese People's Liberation Army. According to the diameter of the lesions, they were divided into two groups of diameter ≤4 cm and group of diameter > 4 cm. The data was analyzed by using χ(2) to compare clinical data and tumor imaging characteristics between the two groups. Results: Thirty-four patients had 34 hypovascular lesions.The solid part of the tumor showed a slightly hypo- and isointense in 31 lesions, and high signal in 3 lesions; T(1)WI showed slightly lower and equal signal in 29 lesions and high signal in 5 lesions; DWI showed equal low signal in 10 lesions, 24 tumors were mainly high signal; 33 lesions showed pseudo-capsule; tumor hemorrhage in 12 lesions, necrosis in 9 lesions and cystic change in 22 lesions, lipid component in 4 lesions. There were 19 lesions with diameter ≤ 4 cm and 15 lesions with diameter > 4 cm. The surgical methods and bleeding in the lesion were statistically different between the two groups (P<0.05). Conclusion: The MRI findings of hypovascular clear cell RCC are low signal on T(2)WI, high signal on DWI mainly, less lipid. Laparoscopic radical resection was more suitable for lesions with diameter >4 cm and these lesions were more likely to bleed within the tumor.

HYOU1 promotes cell growth and metastasis via activating PI3K/AKT signaling in epithelial ovarian cancer and predicts poor prognosis.

OBJECTIVE: Hypoxia upregulated 1 (HYOU1) has been reported to be abnormally expressed in different malignancies, especially in breast cancer. However, the role of HYOU1 in epithelial ovarian cancer (EOC) remains largely unclear. This study aimed to explore the expression and function of HYOU1 in EOC progression. PATIENTS AND METHODS: HYOU1 levels in EOC tissues and cell lines were investigated by RT-PCR. The clinical and prognostic significance of HYOU1 in 127 cases of EOC was analyzed using the Chi-square analysis, Kaplan-Meier analysis, and the Cox proportional hazards regression model. We have also performed multiple cells experiments to evaluate the effects of HYOU1 on EOC cell proliferation, apoptosis, migration, and invasion. The protein levels of associated PI3K/Akt signaling pathway was detected using Western blot assay. RESULTS: We found that the expression levels of HYOU1 were significantly upregulated in both EOC tissues and cell lines. A higher expression of HYOU1 was associated with advanced FIGO stage, LN metastasis, and shorter overall survival. In addition, univariate and multivariate analysis identified high HYOU1 expression as an unfavorable prognostic factor for overall survival. Functional assays revealed that the inhibition of HYOU1 suppressed the tumor proliferation and colony formation, as well as the migratory and invasive capacity. Finally, when HYOU1 was silenced, the results of Western blot showed that the levels of p-PI3K, p-Akt, as well as cell cycle and EMT genes, were respectively downregulated. CONCLUSIONS: Our findings highlighted the targeting of HYOU1 as a novel therapeutic approach for the treatment of EOC.

[Application of multimode MRI in prediction of nuclear grade of clear cell renal cell carcinoma].

Objective: To investigate the predictive value of multimode MRI features for nuclear grade of clear cell renal cell carcinoma (ccRCC). Methods: From January 2016 to October 2017, 381 patients (387 tumors) with ccRCC proven by pathology in Chinese PLA General Hospital First Medical Center were enrolled (male 293, female 88, age 24-87 years old). The clinical and imaging data of these patients were retrospectively analyzed, including clinical information (gender, age, BMI, smoke, hypertension) and preoperative renal MRI. Pre-and post-contrast MRI features were subjectively scored. The largest diameter of each lesion was measured. Two-sample t-test,Chi-squared test and binuary Logistic regression analysis were used to evaluate the predictive efficacy of clinical and MRI data. Results: According to WHO/ISUP nuclear grade system,all ccRCCs (n=387) were divided into low grade (n=322) and high grade group (n=65). Between two groups, there were significant differences in age and diameter((54±12) vs (59±10) years old, P=0.001; (4.1±2.2) vs (6.2±3.0) cm, P<0.01). In MRI scores,there were significant differences in scores of pseudocapsule, shape and margin,hemorrhage,enhancement degree,cystic-solid,intratumoral vessel,peritumoral vessel, renal sinus invasion, vein thrombosis, lymphadenopathy, necrosis, perinephric invasion and metastasis, DWI signal intensity between high grade group and low grade group (all P<0.01). Binuary Logistic regression analysis showed that shape and margin, enhancement degree and DWI signal intensity were independent predictors for high grade ccRCC (OR=0.181, 95%CI 0.049-0.666; OR=0.393, 95%CI 0.182-0.846; OR=0.336, 95%CI 0.155-0.728). A nomogram model for predicting the risk of high grade ccRCC was constructed. Conclusions: Multimode MRI features can differentiate low grade and high grade ccRCC. The nomogram developed in this study might aid urologist in the pre-operative prediction of nuclear grade of ccRCC,which might contribute to developing treatment strategy.

[Significance of pelvic contrast enhanced MRA prior to prostatic artery embolization].

Objective: To assess the values of pelvic contrast enhanced magnetic resonance angiography (MRA) in detection of prostatic artery prior to prostatic arterial embolization(PAE). Methods: This multicenter, prospective study from 5 hospitals in China consisted of 47 patients (mean age (69±16) years, range 56-83 years) who underwent PAE for benign prostatic hyperplasia (BPH) between January 2016 and April 2018, preprocedural prediction of prostatic arteries were determined using contrast enhanced MRA.CE-MRA findings were compared with subsequent intraprocedural digital subtraction angiography (DSA) or DSA combined with cone-beam computed tomography (CT) to assess the sensitivity and specificity with which contrast enhanced MRA predicted the number and origins of prostatic artery, also to assess the optimal oblique projection of PA. Results: In total, 47 patients (94 pelvic sides) with 97 PAs confirmed by DSA or DSA combined with cone-beam CT at the time of embolization, MR angiography successfully identified 88 PAs and their origins , the sensitivity and specificity was 90.7% (88/97) and 93.6% (88/94), respectively.MR angiography correctly determined the bilateral prostatic artery origins in 36 (76.6%) cases.According to the optimal oblique projection of PAs suggested by MR angiography, the origins and trajectory of PAs of all patients underwent PAE with the same oblique projection (20°-45°ipsilateral anterior oblique direction) were clearly displayed when performed the first arteriography. Conclusion: Pelvic contrast enhanced MR angiography with high sensitivity and specificity in detection the origin, trajectory and number of PAs, and it could provide useful information regarding prostatic arteries before PAE.

[Magnetic resonance imaging findings and differential diagnosis of renal epithelioid angiomyolipoma comparing with renal no-epithelioid angiomyolipoma].

Objective: To investigate whether MRI findings can differentiate renal epithelioid angiomyolipoma (EAML) from renal no-epithelioid (typical) angiomyolipoma. Methods: A total of 44 patients were collected from General Hospital of PLA.These cases were obtained from January 2009 to June 2015.To retrospectively analyze these mainly MRI findings among 12 cases of EAML (age from 27 to 61 years, male 2 cases, female 10 cases, mean age was 46.7 years); 32 cases of renal no-epithelioid AML (age from 34 to 70 years old, male 9 cases, female 23 cases, mean age was 53.4 years old) as case control study. MRI findings included gender, T(2)WI, the signal on gross fat, pseudocapsle, necrosis or cystic degeneration, DWI, hemorrhage and the peak in three phases of dynamic enhancement.All data were analyzed statistically using SPSS version 19.0 (IBM, Armonk, NY, USA). χ(2) test and a single order chart were used to analyze the enumeration data. Results: Comparing with renal no-epithelioid angiomyolipoma, minimal fat, necrosis or cystic degeneration and hemorrhage were statistical significance. P values were 0.002, 0.007, 0.025, respectively.Gender, solid components of tumors on T(2)WI, the signal of DWI, pesudocapsule and the peak of enhancement had no statistical significance. P values were 0.863, 0.053, 0.479, 0.460, respectively. Conclusion: Comparing with renal no-epithelioid AML, necrosis or cystic degeneration and hemorrhage with minimal fat are characteristic MRI findings of EAML.

[CT texture analysis in bladder carcinoma: histologic grade characterization].

Objective: To explore the value of CT texture analysis (CTTA) in differentiating the pathological grade of urothelial carcinoma of the bladder (UCB). Methods: A total of 53 lesions from 43 patients with bladder cancer confirmed by postoperative pathology were retrospectively analyzed, including 27 cases of high-grade urothelial carcinoma (HGUC) and 26 cases of low-grade urothelial carcinoma (LGUC). All the patients took pelvic CT and enhanced scanning in the same CT scanner with same scanning parameters. Lesions on both plain and enhanced CT images were delineated on software by two radiologists to extract the corresponding volumes of interest (VOI) and then 92 parameters based on feature classes were generated. The average values of two radiologists were obtained. The difference parameters between HGUC group and LGUC group were screened by nonparametric test, and the receiver operating characteristic (ROC) was drawn. The corresponding optimal thresholds were determined and diagnostic effect was assessed. Results: Nine difference texture parameters between HGUC group and LGUC group were selected, including 5 parameters on unenhanced images, namely, skewness, root mean squared, cluster shade, zone percentage and large area high gray level emphasis. There were 4 parameters on enhanced images, namely, skewness, kurtosis, cluster shade and zone percentage. The largest area under curve of 0.840±0.058 (95% CI 0.726-0.955) was obtained from skewness generated by VOI of unenhanced images. The cut-off value of skewness was 0.186 5, which permitted the diagnosis of HGUC with sensitivity of 92.59%, specificity of 73.08%, positive predictive value of 78.13%, negative predictive value of 90.48% and accuracy of 83.02%. Conclusion: CTTA can effectively distinguish between LGUC and HGUC. Skewness from unenhanced CT images had the optimal diagnostic performance.

Germanene on single-layer ZnSe substrate: novel electronic and optical properties.

In this work, the structural, electronic and optical properties of germanene and ZnSe substrate nanocomposites have been investigated using first-principles calculations. We found that the large direct-gap ZnSe semiconductors and zero-gap germanene form a typical orbital hybridization heterostructure with a strong binding energy, which shows a moderate direct band gap of 0.503 eV in the most stable pattern. Furthermore, the heterostructure undergoes semiconductor-to-metal band gap transition when subjected to external out-of-plane electric field. We also found that applying external strain and compressing the interlayer distance are two simple ways of tuning the electronic structure. An unexpected indirect-direct band gap transition is also observed in the AAII pattern via adjusting the interlayer distance. Quite interestingly, the calculated results exhibit that the germanene/ZnSe heterobilayer structure has perfect optical absorption in the solar spectrum as well as the infrared and UV light zones, which is superior to that of the individual ZnSe substrate and germanene. The staggered interfacial gap and tunability of the energy band structure via interlayer distance and external electric field and strain thus make the germanene/ZnSe heterostructure a promising candidate for field effect transistors (FETs) and nanoelectronic applications.

[Effects of percutaneous nephrolithotomy in the treatment of medullary sponge kidney with calculi].

Objective: To evaluate the effects of percutaneous nephrolithotomy (PNL) in the treatment of medullary sponge kidney with calculi. Methods: A total of 77 patients (91 renal units) of medullary sponge kidney with calculi (MSK group) and 77 patients (77 renal units) with common kidney stone (control group) received PNL at Department of Urology in Peking University People's Hospital from September 2006 to February 2016 were analyzed retrospectively. The MSK group included 33 males and 44 females with a mean age of (42.1±13.2) years, the mean stone burden was (3.9±1.8) cm. The control group included 36 males and 41 females with a mean age of (45.3±13.0) years, the mean stone burden was (3.6±1.5) cm. The numbers of tracts, the time of operation, the drop of hemoglobin, the change of creatine, the time of hospitalization, the stone free rate and major complications were compared between the two groups. The measurement data and numeration data were compared with t test and χ(2) test. Results: There were no significant differences in sex, age, preoperative urinary tract infection, stone type, and stone burden between the two groups (all P>0.05). The proportion of bilateral renal calculus in MSK group was higher (18.2% vs. 0, χ(2)=15.400, P=0.000). There were 159 percutaneous channels were established in MSK group while 90 percutaneous channels were established in control group. Compared with the control group, the operation time ((88.1±37.5) minutes vs. (68.5±30.1) minutes, t=3.543, P=0.000) and hospitalization time ((15.1±8.3) days vs. (10.1±3.6) days, t=4.816, P=0.000) were longer, the creatinine level increased ((101.2±62.6) µmol/L vs. (71.3±23.6) µmol/L, t=3.777, P=0.000), the rate of stone free decreased (27.5% vs. 83.1%, χ(2)=51.840, P=0.000) and the rate of complications increased (29.9% vs. 11.7%, χ(2)=8.114, P=0.004) in MSK group. There was no statistically difference in hemoglobin drop ((12.5±13.2) g/L vs. (13.0±10.9) g/L, t=-0.260, P=0.795). Conclusions: Using PNL for patients of MSK with calculi has a lower stone free rate and a higher complications. It is an effective method for patients of MSK with large and complex calculi.

[Characteristics of ureteral stone position and dilatation of ureter in patients before treated with endourologic lithotripsy].

OBJECTIVE: To investigate the position and the size of ureteral stone in patients before treated with ureteroscopic lithotripsy or percutaneous nephrolithotomy (PCNL), as well as the dilatation of ureter caused by stone, which may be helpful for better understanding of pathogenesis of ureteral stone and improvement of the diagnosis and treatment in clinic. METHODS: A total of 129 cases with ureteral stone for endourologic lithotripsy in Peking University People's Hospital from Aug. 2016 to Mar. 2017 were included for the retrospective review. The CT data of the ureteral stones and the ureteral dilatation were collected, including the position of stone, the transverse and longitudinal diameter of stone, and the transverse diameter of dilated upper ureter and ureteropelvic junction (UPJ). The distribution of ureteral stones and dilatation in different parts of ureter were compared and analyzed. RESULTS: All of the 129 cases of ureteral stone, stones were located at UPJ in 9 cases (7.0%), proximal ureter in 75 (58.0%), ureter crossing external iliac vessel (UEIV) in 6 (4.7%), distal ureter in 26 (20.2%), and ureterovesical junction (UVJ) in 13 (10.1%). The mean transverse diameter of proximal ureteral stones was greater than that of distal ureteral stones [(8.47±2.36) mm vs. (6.74±1.99) mm, P<0.001], as the same as the mean longitudinal diameter [(11.00±4.41) mm vs. (7.50±4.28) mm, P<0.001]. In 114 cases of dilated ureter for stone, the UPJ had a greater transverse diameter compared with the upper ureter [(14.39±6.09) mm vs. (11.45±3.85) mm, P<0.001]. CONCLUSION: The most common location of stone is the proximal ureter in patients for endourologic lithotripsy, as the location in UEIV is rare. Both transverse and longitudinal diameters of stone in proximal ureter are greater than those in distal ureter. For dilated ureter, it is more severe in UPJ than in upper ureter. Traditionally, it is accepted that the stones lodge at 3 sites of natural narrowing in ureter, which may be questioned.

A two-dimensional van der Waals CdS/germanene heterojunction with promising electronic and optoelectronic properties: DFT + NEGF investigations.

Two new 2D materials, germanene and monolayer cadmium sulfide (CdS), have been theoretically predicted and experimentally fabricated recently. In this work, we conduct a systematic investigation of the geometry structure, electronic, optical, and transport properties of a CdS/germanene heterojunction by using density functional theory (DFT) combined with the nonequilibrium Green's function (NEGF) formalism. Despite the gapless nature of germanene, the CdS/germanene heterojunction is found to be a direct band gap semiconductor, with a band gap of 0.644 eV. In particular, applying external strain can effectively tune the electronic band structure and optical properties of the CdS/germanene bilayer in a wide range, and a semiconductor-metal transition can even be achieved. In addition, the transport property calculations show that the current-voltage (I-V) relation of the CdS/germanene bilayer exhibits sensitive responses to the applied strain with a marked change in the I-V relation. Such superior electronic, optical, and transport properties make the CdS/germanene heterobilayer a promising candidate for electronic and optical device applications.

[Quantitative comparison of diffusion weighted image in liver at two field strengths for chronic hepatitis B].

Objective: To evaluate whether there were differences between apparent diffusion coefficient (ADC) values derived from 3.0 T and 1.5 T MR diffusion-weighted imaging (DWI) in liver of patients with chronic hepatitis B. Methods: From January 2016 to November 2016, a total of 40 chronic hepatitis B prospectively underwent both 1.5 T and 3.0 T DWI before liver biopsy, the interval between two scans was within 15 minutes, the protocol was respiratory-triggered DWI(RT-DWI). The ADC values were measured at both field strengths using ROI method. Bland-Altman tests and paired t-tests were used to compare ADC values obtained at 1.5 T and 3.0 T. Results: The ADC values of different b values for patients with mild inflammation at 1.5 T were(1.22-1.48(1.35±0.08)×10(-3) mm(2)/s), the ADC values of different b values for patients with mild inflammation at 3.0 T were(1.18-1.45(1.30±0.08)×10(-3) mm(2)/s); the ADC values of different b values for patients with moderate to severe inflammation at 1.5 T were(1.11-1.37(1.25±0.06)×10(-3) mm(2)/s), the ADC values of different b values for patients with moderate to severe inflammation at 3.0 T were(1.08-1.31(1.20±0.06)×10(-3) mm(2)/s). There were significantly differences between the ADC values of different b values for patients with chronic hepatitis B obtained at two field strengths (P<0.01). Conclusions: Different field strengths have influence on ADC values in liver, the ADC values derived from 3.0 T are lower than the ADC values derived from 1.5 T.

[Study of diffusion weighted imaging in combination with conventional MRI signs for inflammation activity of chronic hepatitis B].

Objective: To study the correlation between ADC values of diffusion weighted imaging (DWI) and the pathological grading in inflammation activity of chronic hepatitis B, and combined with conventional MRI features to predict the diagnosis effectiveness. Methods: A total of 142 cases of patients with chronic hepatitis B were selected as inflammatory group in 302 Hospital of PLA from January 2014 to December 2015, while 20 cases of healthy subjects without history of liver disease were chosen as control group.All patients underwent MR plain scan and dynamic contrast enhancement and DWI examinations (b=0, 800 s/mm(2)) for liver, and were performed liver biopsy within two days.According to the degree of inflammation activity (G), the inflammation group was divided into G1, G2 and G3-4 level.The apparent diffusion coefficient (ADC) value, and the MRI features of each group were analyzed. Results: The ADC values showed statistical difference (F=8.392, P<0.01) within inflammation group of chronic hepatitis B from different pathologic grading, and there was significant negative correlation between ADC values and liver inflammation activity grading (r=-0.613, P<0.01). The ADC value of inflammation group and control group was (1.31±0.16), (1.12±0.15)×10(-3) mm(2)/s, the difference was statistically significant (P<0.05). The ADC value of G1, G2 and G3-4 level was (1.22±0.12), (1.05±0.12), (0.98±0.10)×10(-3) mm(2)/s respectively, and there was statistical difference (P<0.05) between G1 and G2, G1 and G3-4. The receiver operating characteristic (ROC) curve in diagnosis of equal and above G2 level showed the area under the curve (AUC) was 0.880, the sensitivity and the specificity was 82.4% and 76.8% respectively, the diagnostic cut-off value was 1.09×10(-3) mm(2)/s.Besides, the detection rate of portal around its orbit and gallbladder wall edema in inflammation group had statistical difference (P<0.05), and there was no statistical difference in the detection rate of abnormal liver arterial enhancement, hilus lymph node increases and ascites in inflammation group(P>0.05). The ROC in diagnosis of equal and above G2 level by ADC values combined with the MRI characteristic signs showed AUC was 0.938, the sensitivity and the specificity was 88.4% and 88.9% respectively. Conclusions: ADC values can predict the inflammation activity of chronic hepatitis B with quantitatively and non-invasively.Combining with characteristic MRI signs, ADC values can improve the diagnosis efficiency.