[Evaluation of anticoagulant effect and predicted dose of low molecular weight heparin in hemodialysis by anti-â ©a factor activity].

The purpose of this study was to explore the reasonable dose of low molecular weight heparin (LMWH) in hemodialysis (HD) and the strategy of preventing extracorporeal circuit coagulation (ECC). A retrospective case-control study included patients who used LMWH for anticoagulation during maintenance hemodialysis (MHD) in the Hemodialysis Center of Beijing Hospital from December 2020 to January 2021. Basic data such as weight, height, basic kidney disease, dialysis age and anti-Ⅹa factor activity before, during and after dialysis were collected. A total of 46 patients were enrolled in this study, including 5 patients in coagulation group (10.9%) and 41 patients in non-coagulation group (89.1%). The anti-Ⅹa factor activity reached its peak at 0.5 h after the start of HD. The level of anti-Ⅹa factor was incorporated into the receiver operating characteristic curve (ROC curve). The results showed that the area under the ROC curve (AUC) was 0.802 (95% confidence interval: 0.651-0.54, P=0.029), and the cutoff was 0.31 IU/ml (sensitivity 1, specificity 0.683). It is suggested that the body surface area should be used as the basis to estimate the anticoagulant dose of LMWH in HD, and the activity of HD 4 h anti-Ⅹa factor ≤0.31 IU/ml, which is of diagnostic value for ECC. In addition, the results of binary logistic regression analysis showed that dialysis age was an independent risk factor for ECC (OR value 1.319, 95%CI 1.052-1.654, P=0.017). In summary, this study reveals that dialysis age may be a risk factor for ECC and that the activity of HD 4 h anti-Ⅹa factor ≤0.31 IU/ml can be used as a potential diagnostic cut-off point for ECC in HD patients, which provides a scientific basis for monitoring strategies to prevent blood coagulation in HD filters.

Development of a laser-based angle-resolved-photoemission spectrometer with sub-micrometer spatial resolution and high-efficiency spin detection.

Angle-resolved photoemission spectroscopy with sub-micrometer spatial resolution (µ-ARPES), has become a powerful tool for studying quantum materials. To achieve sub-micrometer or even nanometer-scale spatial resolution, it is important to focus the incident light beam (usually from synchrotron radiation) using x-ray optics, such as the zone plate or ellipsoidal capillary mirrors. Recently, we developed a laser-based µ-ARPES with spin-resolution (LMS-ARPES). The 177 nm laser beam is achieved by frequency-doubling a 355 nm beam using a KBBF crystal and subsequently focused using an optical lens with a focal length of about 16 mm. By characterizing the focused spot size using different methods and performing spatial-scanning photoemission measurement, we confirm the sub-micron spatial resolution of the system. Compared with the µ-ARPES facilities based on the synchrotron radiation, our LMS-ARPES system is not only more economical and convenient, but also with higher photon flux (>5 × 1013 photons/s), thus enabling the high-resolution and high-statistics measurements. Moreover, the system is equipped with a two-dimensional spin detector based on exchange scattering at a surface-passivated iron film grown on a W(100) substrate. We investigate the spin structure of the prototype topological insulator Bi2Se3 and reveal a high spin-polarization rate, confirming its spin-momentum locking property. This lab-based LMS-ARPES will be a powerful research tool for studying the local fine electronic structures of different condensed matter systems, including topological quantum materials, mesoscopic materials and structures, and phase-separated materials.

Impact of the radiation effect on the energy storage density and wake-up behaviors of antiferroelectric-like Al-doped HfO2 thin films.

The effect of the γ-ray total dose radiation on the energy storage density (ESD) and the phase transition of antiferroelectric-like (AFE-like) Al-doped HfO2 (HfAlO) thin films was investigated. The ESD property and wake-up behavior of the phase transition during the field cycling of the AFE-like HfAlO thin films were quantified before and after the radiation. The efficiency of the AFE-like thin films for energy storage slightly decreases as the total dose increases from 200 krad (Si) to 5 Mrad (Si), which is attributed to the radiation-induced trapped defects at the interfaces of HfAlO/TiN. Both the J-E, C-V, and εr-f characteristics of the AFE-like HfAlO thin films were also measured before and after the radiation at the same electrodes. These results further confirm that the ferroelectricity of the thin films can be reduced due to the radiation oxide trapped defects. It is worth noting that an enhanced wake-up behavior of the AFE-like HfAlO thin films can be observed after the radiation, which indicates that the transition from the antiferroelectric phase to the ferroelectric phase could be accelerated by the increased radiation-induced defects.

[Efficacy analysis on laparoscopic simultaneous resection of primary colorectal cancer and liver metastases].

Objective: To investigate the short-term outcomes of laparoscopic simultaneous resection of primary colorectal cancer and liver metastases in patients with resectable synchronous colorectal liver metastases (SCRLM). Methods: A descriptive case series study was performed. Clinicopathological data of patients with SCRLM who underwent laparoscopic simultaneous resection of colorectal cancer and liver metastases in Zhongshan Hospital between December 2015 and September 2018 were retrieved from a prospective colorectal cancer database. Perioperative presentations and short-term outcomes were analyzed. Results: A total of 53 patients were enrolled with average age of(61.7±11.3) years. Among them, 32 were male (60.4%) and 21 were female (39.6%). Twenty-five patients (47.2%) were American Society of Anesthesiologists (ASA) grade I and 28 (52.8%) were grade II. All the patients completed laparoscopic simultaneous resection without conversion. The average operation time was (320.2±114.5) min. The estimated blood loss was 150.0 (45.0-2000.0) ml, and only 2 cases (3.8%) received intraoperative transfusion. Postoperative pathologic results revealed that the average primary tumor size was (5.4±1.9) cm; 4 cases (7.5%) were T1-2 stage and 48 cases (90.6%) were T3-4 stage; 40 patients (75.5%) had lymph node metastasis; 19 (35.8%) had vascular involvement; 24 (45.3%) had neural invasion. The median number of liver metastases was 1.0 (1-8), and the average size of largest liver metastases was (3.0±1.9) cm. The median margin of liver metastases was 1.0 (0.1-3.5) cm, and only 1 case was R1 resection. The average time to the first postoperative flatus was (67.9±28.9) h, and the average time to the liquid diet was (107.0±33.8) h. The average postoperative indwelling catheterization time was (85.6±56.4) h. The average postoperative hospital stay was (9.2±4.4) d, and the average cost was (82±26) thousand RMB. No death within postoperative 30-day was found. The morbidity of postoperative complication was 32.1% (17/53) and 3 patients developed grade III to IV complications which were improved by conservative treatment. The median follow-up period was 23.2 months. During follow-up, 19 patients (35.8%) developed recurrence or metastasis, and 4 (7.5%) died. The 1- and 2-year disease-free survival (DFS) rates were 68% and 47% respectively, and the 1- and 2-year overall survival rates were 95% and 86% respectively. Conclusions: Laparoscopic simultaneous resection of primary colorectal cancer and liver metastases is safe and feasible in selected patients with SCRLM. Postoperative intestinal function recovery is enhanced, and morbidity and oncological outcomes are acceptable.

[Relationship between liver controlled attenuation parameters and body fat mass and its distribution].

Objective: To explore the relationship between liver controlled attenuation parameters (CAP) and body fat mass and its distribution. Methods: From May to December 2018, 978 adult patients visited at the fatty liver center of the Third People's Hospital of Changzhou were treated. The patient's liver controlled attenuation parameters were measured by transient elastography and the body fat mass and its distribution were measured by bioelectrical impedance technology. Pearson's correlation coefficient was adopted to describe the correlation between liver CAP value and body mass index (BMI), body fat mass index (BFMI), trunk fat mass index (TFMI), limbs fat mass index (LFMI) and visceral fat area (VFA). Receiver operating characteristic curve (ROC) and area under the curve (AUC) were used to evaluate BMI, BFMI, TFMI, LFMI and VFA to differentiate the cut-off points and efficacy of CAP for diagnosing grading of fatty liver changes in S0-1 and S2-3. Results: In 653 cases of male, S0 ~ S3 accounted for 4.90%, 3.37%, 22.36% and 69.37%, respectively, and in 325 cases of females, S0 ~ S3 accounted for 7.38%, 6.46%, 13.23% and 72.92%, respectively. Female patients had more visceral, trunk and limbs fat than male (P < 0.01). Body mass, body fat mass, body fat percentage, BMI, BFMI, TFMI, LFMI, and VFA were increased in male and female patients with increasing liver fat grade (P < 0.01). CAP values ​​of male and female patients were positively correlated with BMI, BFMI, TFMI, LFMI and VFA. Percentage of body fat mass increased with increasing liver fat grade (male: F = 13.42, P < 0.001; female: F = 3.22, P = 0.023); while limb fat mass percentage did not increase with liver fat grade (Male: F = 1.13, P = 0.34; female: F = 1.05, P = 0.37). Hepatic steatosis grading (S0 ~ 1 or S2 ~ 3) diagnosed with CAP were distinguished through BMI, BFMI, TFMI, LFMI and VFA. AUC was 0.80 ~ 0.82 in males (P < 0.01), and 0.75 ~ 0.78 in females (P < 0.01). Conclusion: The liver CAP value is positively correlated with the body's limbs, trunk and visceral fat, and has a strong correlation with trunk and visceral fat. BMI, BFMI, TFMI, LFMI and VFA up to some extent can identify the CAP diagnosis of grading of fatty liver changes in S0-1 and S2-3.

[Value of RNA oxidation product 8-oxo-Gsn in evaluating renal function in patients with chronic kidney disease].

Objective: To investigate the relationship of DNA oxidative product 8-oxo-dGsn and RNA oxidative product 8-oxo-Gsn with chronic kidney disease (CKD). Methods: Between January 2015 and December 2016, 146 cases of CKD (30, 30, 31, 30 and 25 cases of CKD stage 1-5, respectively) were collected in the Department of Nephrology in Beijing Hospital. Among them, 70 cases were male, accounting for 47.95%. The age distribution ranged from 21 to 88 years, with an average age of (56.43±16.79) years. Their fasting blood and morning urine were collected. The levels of 8-oxo-dGsn and 8-oxo-Gsn in plasma and urine were quantified by isotope-diluted liquid chromatography mass spectrometry (MS)/MS (ID-LC-MS/MS). Results: The urine 8-oxo-Gsn/Cr in patients with CKD stage 1-5 was (3.07±1.07) µmol/mol, (3.42±1.34) µmol/mol, (3.72±1.47) µmol/mol, (3.90±1.93) µmol/mol and (3.75±2.26) µmol/mol, respectively. The urinary 8-oxo-Gsn content in CKD stage 4 patients was significantly higher than those of other 4 stages (P<0.05). The serum/urine ratio of 8-oxo-Gsn was 0.02±0.02, 0.03±0.02, 0.06±0.04, 0.10±0.05 and 0.34±0.03, respectively, and in CKD stage 4 and 5 patients, it increased significantly, especially in CKD stage 5 cases (P<0.05). Expression of 8-oxo-Gsn had a good correlation with renal function[the Spearman 's correlation coefficient: serum 8-oxo-Gsn and serum creatinine was 0.629 (P<0.001); urine/serum 8-oxo-Gsn and eGFR was 0.799 (P<0.001); serum/urine 8-oxo-Gsn and serum/urine creatinine was 0.888 (P<0.001)]. With age increasing, CKD patients showed increased RNA oxidation, and 8-oxo-Gsn increased significantly in patients over 60 years (P<0.05). After multiple linear regression analysis, 8-oxo-Gsn was only associated with serum creatinine (ß=0.656, t=8.275, P<0.001). Conclusions: Our finding indicates that the RNA oxidation occurs in patients with renal disease, and its oxidation increased as the disease progressing. The significant increase in the ratio of plasma and urinary 8-oxo-Gsn is of great importance on evaluating renal function.

Prenatal Diagnosis of ß-Thalassemia Using Multiplex Allele-Specific Amplification (MASPCR) in Chinese Families.

Combining allele-specific amplification (ASPCR) with multiplex PCR, we developed a new approach-multiplex allele-specific amplification (MASPCR) to detect five common types of ß-thalassemia mutations (CD 41-42(-4bp), CD 17 A→T, CD 71-72 (+ A), -28 A→ G and IVS-2-654 C→ T) which account for approximately 80% of all ß-thalassemia alleles in Chinese individuals. Using this technique, prenatal diagnoses were performed for ten pregnancies at risk for ß-thalassemia. All the results were confirmed by PCR/ASO probe hybridization or DNA sequencing. This study suggests that this method is a simple, accurate approach that may further improve the prevention programs for ß-thalassemia that have already dramatically lowered the birth rate of affected children in some parts of the world.

[Roles of T cell subsets in the protective immunity of mice against Plasmodium yoelii].

BALB/c mice which had developed protective immunity against Plasmodium yoelii (P. y.) challenge were injected with anti-CD4 or anti-CD8 monoclonal antibody, and were then challenged again with P. yoelli. No impairment of protection was observed. CD8+T cells obtained from spleens of these mice were transferred to BALB/c nude mice and induced partial protection, while transfer of CD4+T cells did not so. In P. yoelli-mouse model, the parasites invaded reticulocytes in the early infection, and the infected reticulocytes could be recognized and attacked by sensitized CD8+T cells. In late infection when P. yoelli also invaded mature erythrocytes, the protective effect of CD8+T cells decreased and the main role of protection was played by antibodies.

Construction and screening of Plasmodium falciparum cDNA library.

The HAINAN isolate of Plasmodium falciparum FCC1/HN was cultured in vitro in large quantities. The total parasite mRNA was purified and reverse transcribed into cDNA. The cDNA fragments were inserted into lambda gt11 to construct a P. falciparum FCC1/HN erythrocytic stage cDNA library. Inhibitory monoclonal antibodies (McAbs) M26-32, F6-C2, and F6-D3 were used to screen the cDNA library expressed in E. coli. A total of 27 positive clones were found to react with M26-32 alone and 34 clones with both M26-32 and F6-C2. These expressed proteins may be candidates for use in malaria vaccine.