Structural maintenance of chromosomes (SMC), including cohesin, condensin and the SMC5/6 complex, are protein complexes which maintain the higher structure and dynamic stability of chromatin. Such circular complexes, with similar structures, play pivotal roles in chromatid cohesion, chromosomal condensation, DNA replication and repair, as well as gene transcription. Despite extensive research on the functions of the SMCs, our understanding of the SMC5/6 complex has remained limited compared with the other two complexes. This article has reviewed the architecture and crucial physiological roles of the SMCs, and explored the associated phenotypes resulting from mutations of the SMC components such as Cornelia de Lange syndrome (CdLS) and microcephaly, with an aim to provide insights into their functions in eukaryotic cells and implications for human diseases.

Objective:To investigate the clinical features and outcomes of adolescence-onset methylmalonic acidemia (MMA) and explore preventive strategies.Methods:This was a retrospective case analysis of the phenotypes, genotypes and prognoses of adolescence-onset MMA patients. There were 55 patients diagnosed in Peking University First Hospital from January 2002 to June 2023, the data of symptoms, signs, laboratory results, gene variations, and outcomes was collected. The follow-ups were done through WeChat, telephone, or clinic visits every 3 to 6 months.Results:Among the 55 patients, 31 were males and 24 were females. The age of onset was 12 years old (range 10-18 years old). They visited clinics at Tanner stages 2 to 5 with typical secondary sexual characteristics. Nine cases (16%) were trigged by infection and 5 cases (9%) were triggered by insidious exercises. The period from onset to diagnosis was between 2 months and 6 years. Forty-five cases (82%) had neuropsychiatric symptoms as the main symptoms, followed by cardiovascular symptoms in 12 cases (22%), kidney damage in 7 cases (13%), and eye disease in 12 cases (22%). Fifty-four cases (98%) had the biochemical characteristics of methylmalonic acidemia combined with homocysteinemia, and 1 case (2%) had the isolated methylmalonic acidemia. Genetic diagnosis was obtained in 54 cases, with 20 variants identified in MMACHC gene and 2 in MMUT gene. In 53 children with MMACHC gene mutation,1 case had dual gene variants of PRDX1 and MMACHC, with 105 alleles. The top 5 frequent variants in MMACHC were c.482G>A in 39 alleles (37%), c.609G>A in 17 alleles (16%), c.658_660delAAG in 11 alleles (10%), c.80A>G in 10 alleles (10%), c.567dupT and c.394C>T both are 4 alleles (4%). All patients recovered using cobalamin, L-carnitine, betaine, and symptomatic therapy, and 54 patients (98%) returned to school or work.Conclusions:Patients with adolescence-onset MMA may triggered by fatigue or infection. The diagnosis is often delayed due to non-specific symptoms. Metabolic and genetic tests are crucial for a definite diagnosis. Treatment with cobalamin, L-carnitine, and betaine can effectively reverse the prognosis of MMA in adolescence-onset patients.

Under the organization of Renji Hospital, Shanghai Jiao Tong University School of Medicine, a specialized disease database of inflammatory bowel disease (IBD) cohort was deployed, and a brief introduction of the database was made in this article. The IBD data set was established by referring to domestic and foreign standards. Through data extraction, cleaning, normalization and other information processing technologies, data from multi‑source heterogeneous platform were arranged to form a specialized major disease database of IBD cohort and the efficiency and quality of data collection in clinical practice, teaching and scientific research were guaranteed. The display and personalized export capacities of the database can promote the researches on IBD and assist the clinical decision‑making. It provides not only efficient, comprehensive and reliable research‑level data support for scientific research, but also a precise guidance for diagnosis and treatment of the disease. Furthermore, it can excavate the potential clinical principles based on medical big data.

Objective:To investigate the correlation between Piwi-interacting RNA (piRNA) and diabetic nephropathy (DN).Methods:The differential expression profiles of piRNAs in renal tissues of patients with DN (experimental group) and renal tissues adjacent to tumors of patients with renal tumors (control group) were detected by high-throughput sequencing. The biological function of differentially expressed piRNAs was described by gene ontology and Kyoto encyclopedia of genes and genomes enrichment analysis. Real-time fluorescence quantitative PCR was used to detect the serum expression level of target piRNAs in patients with DN. Spearman correlation analysis was used to analyze the correlation between serum target piRNAs and clinical indexes of patients with DN.Results:The results of high throughput sequencing showed that there were 127 differentially expressed piRNAs between DN group and control group, with screening condition of |log 2(fold changes)|≥2 and P<0.05. Among them, there were 99 up-regulated piRNAs and 28 down-regulated piRNAs. The top 5 up-regulated piRNAs were piRNA-hsa-161686, piRNA-hsa-349255, piRNA-hsa-355720, piRNA-hsa-151229 and piRNA-hsa-154959, respectively. The top 5 down-regulated piRNAs were piRNA-hsa-1929960, piRNA-hsa-174194, piRNA-hsa- 148658, piRNA-hsa-172594 and piRNA-hsa-172421, respectively. The PCR verification results of 3 up-regulated genes and 3 down-regulated genes with low P values and high expression levels showed that serum expression level of piRNA-hsa-77976 was significantly down-regulated in patients with DN ( P=0.028), which was consistent with that of sequencing, while the expression levels of other genes were inconsistent with the sequencing results or had no statistical significance. Bioinformatics analysis results predicted that significantly differentially expressed piRNAs might participate in the regulation of DN through Rap1, Ras, PI3K-Akt and axon guiding pathways. The results of correlation analysis showed that the expression level of piRNA-hsa-77976 was negatively correlated with blood urea nitrogen ( r=-0.584, P=0.028), serum creatinine ( r=-0.637, P=0.014), cystatin C ( r=-0.738, P=0.003) and β2 microglobulin ( r=-0.822, P<0.001), and positively correlated with estimated glomerular filtration rate ( r=0.661, P=0.010). Conclusion:The differential expression of piRNA is closely related to DN, and may be used as a new biomarker for the diagnosis and prognosis of DN.

Although primary vesical calculi is an ancient disease, the mechanism of calculi formation remains unclear. In this study, we established a novel primary vesical calculi model with d,l-choline tartrate in mice. Compared with commonly used melamine and ethylene glycol models, our model was the only approach that induced vesical calculi without causing kidney injury. Previous studies suggest that proteins in the daily diet are the main contributors to the prevention of vesical calculi, yet the effect of fat is overlooked. To assay the relationship of dietary fat with the formation of primary vesical calculi, d,l-choline tartrate-treated mice were fed a high-fat, low-fat, or normal-fat diet. Genetic changes in the mouse bladder were detected with transcriptome analysis. A high-fat diet remarkably reduced the morbidity of primary vesical calculi. Higher fatty acid levels in serum and urine were observed in the high-fat diet group, and more intact epithelia in bladder were observed in the same group compared with the normal- and low-fat diet groups, suggesting the protective effect of fatty acids on bladder epithelia to maintain its normal histological structure. Transcriptome analysis revealed that the macrophage differentiation-related gene C-X-C motif chemokine ligand 14 (Cxcl14) was upregulated in the bladders of high-fat diet-fed mice compared with those of normal- or low-fat diet-fed mice, which was consistent with histological observations. The expression of CXCL14 significantly increased in the bladder in the high-fat diet group. CXCL14 enhanced the recruitment of macrophages to the crystal nucleus and induced the transformation of M2 macrophages, which led to phagocytosis of budding crystals and prevented accumulation of calculi. In human bladder epithelia (HCV-29) cells, high fatty acid supplementation significantly increased the expression of CXCL14. Dietary fat is essential for the maintenance of physiological functions of the bladder and for the prevention of primary vesical calculi, which provides new ideas for the reduction of morbidity of primary vesical calculi.

BACKGROUND: Sand therapy has been shown to exhibit a positive effect on reducing femoral atherosclerosis and inhibiting thrombosis. OBJECTIVE: To investigate the effects of sand therapy on hemodynamic parameters of different stenosis models of femoral bifurcation through comparing the hemodynamic parameters and wall shear stress in four stenosis models before and after sand therapy. METHODS: The study protocol was performed in strict accordance with the relevant ethical requirements of School of Mechanical Engineering of Xinjiang University. Each participant provided written informed consent. Medical software Mimics10.01, reverse engineering software Geomagic Studio 2012 and three-dimensional CAD software UG8.5 were used to separate and optimize the CT data of a subject’s lower extremities and the geometric model of the femoral artery bifurcation was obtained. According to the classification criteria of vascular stenosis caused by femoral atherosclerotic plaque in the lower extremity, the degree of plaque stenosis on the side wall of the femoral bifurcation tube was set as 0% (normal), 15% (normal), 30% (mild) and 50% (moderate). Computational fluid dynamics method was used for numerical simulation. The Laminar flow model was selected for blood flow before sand therapy, and the standard turbulence model κ-ε was selected for blood flow after sand therapy. Blood flow velocity and wall shear stress were analyzed before and after sand therapy. RESULTS AND CONCLUSION: The maximum blood flow velocity after sand therapy was 0.35-0.45 m/s higher than that before sand therapy. After sand therapy, the wall shear stress at the stenosis was increased by 5-11 Pa compared with that before sand therapy, and the wall shear stress at 50% vascular stenosis rate model reached 41 Pa. These results suggest that the trend of atherosclerotic plaque enlargement is decreased after sand therapy, but patients with 50% (moderate) vascular stenosis have the risk of plaque rupture.

Background: Inflammatory bowel disease (IBD) affects the digestive tract, and the prevalence of malnutrition is high. Recently, bioelectrical impedance analysis (BIA) has been frequently used clinically for nutritional assessment. Aims: To study the nutritional status of hospitalized IBD patients through BIA combined with serological indicators. Methods: Data from hospitalized IBD patients who underwent BIA test at Renji Hospital, School of Medicine, Shanghai Jiao Tong University between Jan. and Dec. 2015 were collected retrospectively. In the 198 patients enrolled, 129 were Crohn's disease (CD) and 69 were ulcerative colitis (UC). Serological results, as well as BIA results and related indices were compared between CD and UC patients. Results: The serum vitamin B12 level, body weight and body fat mass were significantly lower in patients with CD than in those with UC (P<0.05), while the prevalence of underweight was significantly higher in CD patients than in UC patients (P<0.05). The serum cholesterol level, body fat percent, body mass index (BMI), fat free mass index (FFMI), body cell mass index (BCMI) and skeletal muscle mass index (SMMI) were significantly lower in male CD patients than in male UC patients (P<0.05), whereas no significant differences in these parameters were observed between female CD and female UC patients (P>0.05). Differences in BMI and BCMI between active CD and CD in remission were insignificant (P>0.05). Conclusions: Among the hospitalized IBD patients, males with CD have worse nutritional status than males with UC. Except for serum vitamin B12, there is no significant difference in nutritional status between female CD and female UC patients. BIA related indices are effective tool for assessment of nutritional status, which may be used as a complement to BMI.

Objective To study the effect of sand therapy on the hemodynamics of flexural femoral artery, and further reveal the therapeutic mechanism of sand therapy from the perspective of hemodynamics. Methods The three-dimensional finite element model of the curved femoral artery was established based on CT images of human aorta, and the data of heart rate, peak blood flow velocity and inner diameter of femoral artery measured by the experiment were used as initial conditions and boundary conditions to carry out finite element numerical simulation. The blood flow velocity, pressure and wall shear stress before and after sand therapy were analyzed and compared under fluid-solid coupling condition. Results Compared with treatment before sand therapy, the longitudinal velocity of the flexural segment of blood vessel increased significantly, with an increase of 22.76%. The secondary reflux velocity decreased significantly, with a relative decrease of 18.26%. The wall shear stress decreased by 2.01% after sand therapy. Conclusions Sand therapy had a significant effect on blood fluidity, by improving blood flow of femoral arteries, and preventing deposition of arterial platelets. The transverse flow phenomenon was obviously weakened after sand therapy, which could avoid the deposition of substances in blood and had a positive effect on the prevention of atherosclerosis, thrombosis and other vascular diseases.

This paper summarized the nursing experience of one infant with right lower limb ischemia caused by amniotic band syndrome. The nursing key points included:careful observation of the infant condition,exposing the wound,raising the affected limb,wound disinfection,and removing necrotic tissues at the surface skin,applying topical drugs for promoting tissue growth and antibiotics,selecting appropriate dressing to provide suitable environment for tissue regeneration;debridement of inguinal skin,dressing change,assessing pain and providing corresponding care during debridement;infection prevention. After 29 days of treatment and careful nursing care,the skin damage was repaired on the right lower limb,swelling subsided,the necrotic tissues at right inguinal region were completely cleared,granulation tissue was formed,and the infant was discharged smoothly.

DNA copy number variation is an important pathogenic factor of human diseases and might be involved in the pathogenesis and pathological process of inflammatory bowel disease (IBD).Aims: To investigate the copy number variation of CNTNAP3 gene and its significance in Crohn''s disease (CD).Methods: A total of 101 active CD patients admitted from Jul.2009 to Dec.2010 at Renji Hospital, School of Medicine, Shanghai Jiao Tong University were enrolled.Eighty healthy subjects were served as controls.Peripheral blood or intestinal mucosa samples of CD patients were collected, and the copy number variation of CNTNAP3 gene was screened and validated by array-based comparative genomic hybridization (aCGH, n=8) and real-time PCR (n=93);expression of CNTNAP3 encoding protein was determined by ELISA (n=55).Results: A large fragment copy number amplification was revealed by aCGH at chromosome 9p13 region (including CNTNAP3 gene) in untreated CD patients.Real-time PCR confirmed that the copy number of CNTNAP3 gene was amplified in peripheral blood of CD patients, especially steroid-naive patients as compared with the normal controls (208 616.4±126 984.7 and 233 453.3±113 520.8 vs.161 750.2 ±53 940.3, P<0.05 and P<0.01).In the clinical parameters analyzed in this study, only smoking was significantly correlated with CNTNAP3 copy number amplification (P<0.05).However, there was no significant difference in plasma CNTNAP3 level between CD patients with amplified copy number and normal controls (P>0.05).Furthermore, the plasma CNTNAP3 level in CD patients with amplified copy number was not correlated with the simplified endoscopic score for CD (P>0.05).Conclusions: Copy number amplification of CNTNAP3 gene might be involved in the pathogenesis of CD in Chinese population.Glucocorticoid treatment and smoking might affect the copy number variation of CNTNAP3 gene.Plasma CNTNAP3 level cannot discriminate CD patients from healthy subjects.Conclusions of this study needs to be further demonstrated and discussed.