Analysis of epidemic characteristics and related factors of norovirus in diarrhea patients in Guangxi, 2015-2020 / 中国热带医学

@#Abstract: Objective　To analyze the epidemiological characteristics and related factors of norovirus in Guangxi from 2015 to 2020, and to provide scientific recommendations for norovirus prevention and control. Methods The foodborne diseases surveillance data were collected from 11 sentinel hospitals through the National Foodborne Disease Monitoring and Reporting System from 2015 to 2020. R software with version 4.0.3 was used for descriptive and statistical analysis, including epidemic curve, chi-square test, and trend chi-square and so on. Logistic regression was used to analyze norovirus-related factors, OR values and 95% confidence intervals were calculated respectively with the statistical test level of P<0.05. Results There were 1 008 norovirus cases detected, with a detection rate of 12.75% (1 008/7 903). Children with age less than 5 years (OR=1.43, 95%CI: 1.13-1.82) and patients at age 20-45 (OR=1.45, 95%CI: 1.13-1.87) were high risk population. The detection rate was higher in autumn (OR=1.29, 95%CI: 1.08-1.53) but lower in summer (OR=0.67, 95%CI: 0.55-0.80). In addition, the tourist area (Guilin City) presented a higher detection rate than other areas (OR=1.41, 95%CI: 1.10-1.80). Aquatic products (OR=1.40, 95%CI: 1.03-1.91), meat and dairy products (OR=1.31, 95%CI: 1.06-1.61) were high-risk foods for norovirus infection. The prevention and control policies of COVID-19 can reduce the possibility of norovirus by 61% (OR=0.39, 95%CI: 0.31-0.49) showed a declining trend (Trend χ2=85.33, P<0.001). In addition, prolonged visit time can lead to 19%-23% decrease in the detection rate of norovirus (OR24-48 hours=0.81, 95%CI: 0.70-0.95; OR>48 hours=0.77, 95%CI: 0.63-0.93). Conclusions　The epidemic of norovirus presented seasonal and regional distribution in Guangxi with a declining detection rate trend in diarrhea patients during recent 6 years. Young children were high-risk population in infection norovirus. The intake of seafood can increase the risk of norovirus infection. The prevention and control policies of COVID-19 can sharply decrease the possibility of infection norovirus. The monitoring of key foods such as seafood should be strengthened, and the early screening of suspected cases should be taken. The norovirus monitoring should be improved to ensure the health of the population.

Nutritional literacy and influencing factors among students from Nutrition Improvement Program for Rural Compulsory Education Students in Chongqing / 中国学校卫生

Objective@#To analyze the nutritional literacy and influencing factors among students from Nutrition Improvement Program for Rural Compulsory Education Students (NIPRCES) in Chongqing, and to provide a scientific basis for improving the nutritional literacy of middle school students in the NIPRCES.@*Methods@#Using cross sectional survey, a total of 3 365 students in the grade 7 and 8 were selected from the middle schools in 12 national pilot districts and 2 Chongqing pilot districts by online survey in September 2020. Students filled out a self designed nutritional literacy questionnaire anonymously. The relative evaluation method was used to convert the nutritional literacy of scores into a percentile, and the median score was used as the criterion for qualified nutritional literacy screening.@*Results@#The median score of nutritional literacy of participants was 63.5, and 64.2% achieved the qualified level. The results of multivariate Logistic regression analysis showed that boarding school ( OR =1.28, 95% CI =1.08- 1.51 ) and no parents as the primary caregiver ( OR =1.22，95% CI =1.05-1.42) were associated with poor nutritional literacy. Urban residence ( OR =0.75, 95% CI =0.63-0.90), NIPRCES local pilot ( OR =0.83, 95% CI =0.71-0.97) and high paternal education ( OR =0.70, 95% CI =0.52-0.95) were associated with higher nutritional literacy ( P <0.01). Classroom was the main channel for students to obtain nutrition information at present (65.1%) and in the future (72.8%).@*Conclusion@#The nutritional literacy among students in the NIPRCES in Chongqing needs to be improved. Nutritional literacy level of students can be strengthened by nutritional education in boarding schools, rural areas, national pilot areas, and primary caregivers.

Direct Synthesis of Bienzyme-like Carbide-derived Carbons via Mild Electrochemical Oxidation of Ti 3AlC 2 MAX / 生物医学与环境科学（英文）

Objective@#To develop effective alternatives to natural enzymes, it is crucial to develop nanozymes that are economical, resource efficient, and environmentally conscious. Carbon nanomaterials that have enzyme-like activities have been extensively developed as substitutes for traditional enzymes.@*Methods@#Carbide-derived carbons (CDCs) were directly synthesized via a one-step electrochemical method from a MAX precursor using an ammonium bifluoride electrolyte at ambient conditions. The CDCs were characterized by systematic techniques.@*Results@#CDCs showed bienzyme-like activities similar to that of peroxidase and superoxide dismutase. We systematically studied the dependence of CDC enzyme-like activity on different electrolytes and electrolysis times to confirm activity dependence on CDC content. Additionally, the synthesis mechanism and CDC applicability were elaborated and demonstrated, respectively.@*Conclusion@#The demonstrated synthesis strategy eliminates tedious intercalation and delamination centrifugation steps and avoids using high concentrations of HF, high temperatures, and halogen gases. This study paves the way for designing two-dimensional material-based nanocatalysts for nanoenzyme and other applications.

Local PatchMatch Based on Superpixel Cut for Efficient High-resolution Stereo Matching

Abstract: Obtaining the accurate disparity of each pixel quickly is the goal of stereo matching, but it is very difficult for the 3D labels-based methods due to huge search space of 3D labels, especially for highresolution images. We present an novel two-stage optimization strategy to get the accurate disparity map for high-resolution stereo image efficiently, which includes feature points optimization and superpixel optimization. In the first stage, we construct the support points including edge points and robust points for triangulation, which is used to extract feature points and then perform spatial propagation and random refinement to get the candidate 3D label sets. In the stage of superpixel optimization, we update per pixel labels of the corresponding superpixels using the candidate label sets, and then perform spatial propagation and random refinement. In order to provide more prior information to identify weak texture and textureless areas, we design the weight combination of "intensity + gradient + binary image" for constructing an optimal minimum spanning tree (MST) to compute the aggregated matching cost, and obtain the labels of minimum aggregated matching cost. We also design local patch surrounding the corresponding superpixel to accelerate our algorithm in parallel. The experimental result shows that our method achieves a good trade-off between running time and accuracy, including KITTI and Middlebury benchmark, which are the standard benchmarks for testing the stereo matching methods.

Semi-rational design improves the catalytic activity of phenylalanine ammonia lyase from Anabaena variabilis / 药学学报

Phenylalanine ammonia lyase (PAL) can catalyze L-phenylalanine to produce trans-cinnamic acid, which is widely used in the fields of pharmacy, food and agriculture. In particular, phenylalanine ammonia lyase from Anabaena variabilis (AvPAL) is the only protein drug for the treatment of phenylketonuria. However, the poor activity and low stability limit the application in industry of AvPAL. In this study, the key amino acids of substrate-binding cavity in AvPAL were identified by screening the single site saturation mutagenesis library. Subsequently, the impact of replacing M222 with the additional 19 amino acids on activity was also evaluated by site-directed mutagenesis. It was found that the kcat values of mutants M222L and M222V were 90% and 60% higher than that of AvPAL, and the kcat/Km was 1.4 and 1.5 times as that of AvPAL. Molecular docking results revealed that the higher activity of M222L and M222V may be due to the increase of hydrophobicity favorable for the substrate-binding cavity. This study is important for elucidating the structure-function relationship of AvPAL.

Herbal Textual Research on Mori in Famous Classical Formulas / 中国实验方剂学杂志

Through consulting the ancient herbs， medical books and modern literature， this paper made textual research on the name， origin， producing area， quality evaluation， collection and processing of medicinal materials of Sang （Mori Folium， Mori Cortex， Mori Ramulus， Mori Fructus） in famous classical formulas， in order to provide a basis for the development of famous classical formulas containing medicinal materials of Sang. According to the research， Mori Folium and Mori Cortex were first used as medicines in Shengnong Bencaojing ， Mori Ramulus was first used as medicine in Jinxiaofang， and Mori Fructus was first used as medicine in Xinxiu Bencao. Before the Tang dynasty， there were Nyusang and Shansang. Since Tang dynasty， there were many sources of medicinal materials of Sang， including Baisang （Morus alba）， Jisang （M. australis）， Shansang （M. mongolica）， etc. According to textual research， the mainstream varieties were M. australis， M. alba and their cultivated varieties. In modern times， according to the relevant information and the Chinese Pharmacopoeia， M. alba is the original base. In ancient times， the origin of mulberry changed with the development of sericulture， mulberry has been widely planted since the Song dynasty. In the Ming and Qing dynasties， mulberry has been planted most in Jiangsu and Zhejiang. In modern times， they are mainly produced in Jiangsu， Zhejiang， Anhui， Hunan and other places. In recent years， due to the related policies and strategies such as "moving silkworms from east to west"， the center of silkworm breeding has gradually transferred to the west. As for the quality evaluation and harvesting and processing of mulberry medicinal materials， Most of the ancient and modern records of Mori Folium are the same. They are harvested after frost， and dried after removing impurities. The quality is better when the leaves are large and thick， yellowish green， holding prickly hands and undergoing frost. The harvesting period of Mori Cortex is slightly different in ancient and modern records. Ancient books record that it can be harvested all the year round， but in modern times， it is mostly harvested from late autumn to the next spring. The processing methods include removing soil and fibrous roots， scraping off yellow-brown rough skin， peeling off white skin and drying in the sun. The quality is better when they are white， thick， flexible， free of rough skin and full of powder. There are few records about the collection， processing and quality evaluation of Mori Ramulus and Mori Fructus in ancient Chinese herbal books. According to modern literature， Mori Ramulus is usually collected in late spring and early summer， with leaves removed， slightly dried， sliced while fresh， and dried in the sun. The best quality of Mori Ramulus is fine and tender with the yellow and white section. Mori Fructus is harvested from April to June when the fruit turns red， and dried in the sun， or slightly steamed and dried in the sun， and it is better to be big， dark purple， oily and thick. There are many processing methods of mulberry medicinal materials. Ancient books record stir frying， baking， burning and steaming of Mori Folium， in modern times， there is honey-roasted method， but most of them are used as raw products. In ancient materia medica， Mori Cortex has firing method， baking method， stir-frying method， honey-fried method， etc. In modern times， there are stir-fried and honey-fried methods， and most of them are used as raw products. Ancient books record that Mori Ramulus has cutting and frying methods， while modern ones have cutting， frying， wine-processed and bran-processed methods. Processing methods of Mori Fructus are consistent in ancient and modern times， and they are mostly dried after being cleaned or steamed. Based on the research results， it is suggested that M. alba should be selected as mulberry medicinal materials in the famous classical formulas， and appropriate medicinal parts and processing methods can be selected according to the indications of the famous classical formulas.

LXYL-P1-2 immobilized on magnetic nanoparticles and its potential application in paclitaxel production

BACKGROUND: LXYL-P1-2 is the first reported glycoside hydrolase that can catalyze the transformation of 7-b-xylosyl-10-deacetyltaxol (XDT) to 10-deacetyltaxol (DT) by removing the D-xylosyl group at the C7 position. Successful synthesis of paclitaxel by one-pot method combining the LXYL-P1-2 and 10- deacetylbaccatin III-10-b-O-acetyltransferase (DBAT) using XDT as a precursor, making LXYL-P1-2 a highly promising enzyme for the industrial production of paclitaxel. The aim of this study was to investigate the catalytic potential of LXYL-P1-2 stabilized on magnetic nanoparticles, the surface of which was modified by Ni2+-immobilized cross-linked Fe3O4@Histidine. RESULTS: The diameter of matrix was 20­40 nm. The Km value of the immobilized LXYL-P1-2 catalyzing XDT (0.145 mM) was lower than that of the free enzyme (0.452 mM), and the kcat/Km value of immobilized enzyme (12.952 mM s 1 ) was higher than the free form (8.622 mM s 1 ). The immobilized form maintained 50% of its original activity after 15 cycles of reuse. In addition, the stability of immobilized LXYL-P1-2, maintained 84.67% of its initial activity, improved in comparison with free form after 30 d storage at 4 C. CONCLUSIONS: This investigation not only provides an effective procedure for biocatalytic production of DT, but also gives an insight into the application of magnetic material immobilization technology.

Breakfast consumption and influencing factors of primary and middle school students in rural poor areas of Guizhou Province / 中国学校卫生

Objective@#To understand the current situation of breakfast consumption and its influencing factors in primary and middle school students in a poor rural area in a city in Guizhou Province, and to provide scientific basis for child nutrition education and intervention.@*Methods@#A stratified cluster sampling method was used to conduct a questionnaire survey of breakfast behavior and influencing factors among 2 833 students from 3 primary schools and 3 middle schools in a area of Guizhou Province from April to June 2019.@*Results@#The most frequently consumed breakfast was rice noodle products(71.66%), followed by fresh vegetables(45.89%), milk(35.55%), meat/egg/fish(29.33%), beans(19.52%), and fresh fruits(18.74%). The proportion of having breakfast everyday among elementary and middle school students who was 62.97%, and having breakfast 4-6 days peer week was 22.80%, and 14.23% with ≤3 days peer week, and the proportion of boys who ate breakfast every day(65.07%) was higher than girls(61.00%)(χ2=10.01, P<0.05). The proportion of low quality breakfast was 71.87%, and girls(73.68%) were higher than boys(69.94%)(χ2=9.29, P<0.05). Logistic regression analysis showed that grade of school, boarding school, and sleep quality are all influencing factors for whether to eat breakfast every day; grade of school, whether to stay at school were factors that affect breakfast quality(P<0.05).@*Conclusion@#The frequency and quality of breakfast need more improvement among middle and primary school students in a poor rural area of a city in Guizhou Province. Students, parents, and teachers should be educated on nutrition to promote healthy eating and sleeping habits and improve student health.

Correlation of Intravoxel Incoherent Motion-derived Parameters with Computer Tomography Perfusion Parameters in Insulinoma / 中国医学科学院学报

To prospectively evaluate the correlation between intravoxel incoherent motion (IVIM)-derived parameters and CT perfusion parameters as well as the pathological grade in insulinoma. A total of 55 patients with suspected insulinoma undergoing IVIM and CT perfusion scans were prospectively enrolled. The images were post-processed to obtain IVIM parameters including apparent diffusion coefficient (ADC),diffusion (D),perfusion correlated diffusion (D*),and f,and CT perfusion parameters including blood flow (BF),blood volume (BV),and permeability (PM). The pathological specimens were stained to obtain pathological parameters including the grading,ki-67 index,and the mitotic count. The IVIM derived parameters of normal pancreas including head,body,and tail as well as that of the pancreatic insulinoma were compared. The correlation between IVIM parameters and CT perfusion parameters as well as the pathological parameters was analyzed. ADC and D values of pancreatic tail were significantly lower than those of the pancreatic head and neck (all 0.05). IVIM parameters differ at different anatomical parts of normal pancreas. IVIM parameters can distinguish normal pancreatic parenchyma from insulinoma. The ADC value is weakly correlated with BF.

Prognostic value of Per2 in hepatocellular carcinoma and its effect on the growth and apoptosis of hepatocellular carcinoma cells / 基础医学与临床

Objective To explore the expression of Per2 in hepatocellular carcinoma (HCC) and its effect on the survival of HCC patients, and to analyze the effects of Per2 on the proliferation and apoptosis of SMMC-7721 cells. Methods The protein expression of Per2 in HCC patients was analyzed by immunohistochemical (IHC) staining. SMMC-7721 cells were transfected with Per2 eukaryotic expression plasmid. The protein expression of Per2 was detected by Western blot. The cell proliferation and apoptosis was detected by MTS and flow cytometry. Results In 117 HCC tissues, the Per2 positive expression rate was 70. 94%, which was significantly lower than that of 87. 18% in the adjacent HCC tissue. The Per2 staining score was 2. 14±1. 76, which was significantly lower than that of 6. 39±3. 84 in the adjacent HCC tissue (P<0. 01). Per2 expression was related to tumor diameter, portal vein invasion and TNM staging(P<0.05) in 117 HCC patients. The overall survival (OS) and recurrence-free survival (RFS) of HCC pa-tients with low expression of Per2 were shorter than those with Per2 high expression(P<0.05).The cell proliferation was significantly inhibited and the apoptosis increased with the transfection of Per2 eukaryotic expression plasmid in SMMC-7721 cells(P<0.05).Conclusions The expression of Per2 in HCC is significantly reduced.Per2 inhibits the progression of HCC,possibly by inhibiting cell proliferation and promoting apoptosis.

Effect of mild hypothermia on renal ischemia/reperfusion injury after cardiopulmonary resuscitation in a swine model

Abstract Purpose: To investigate the effect of intravascular cooling on renal function after resuscitation. Methods: Twenty four pigs were randomized into three groups (n=8 in each group): therapeutic hypothermia group (TH group), normothermia group (NH group) and sham operation group (SHAM group). After 6 minutes of untreated VF, CPR was performed. Upon ROSC, the TH group received the intravascular cooling. The NH and SHAM group did not undergo therapeutic hypothermia. Haemodynamic parameters were recorded. The bloods were analyzed for serum creatinine (sCr), CysC and NGAL. The kidney was surgically removed observe pathologic changes under a light microscope. Results: The sCr increased in both TH and NH groups after ROSC, compared to baseline. Between two groups, the sCr and creatinine clearance (Cc) showed lower level in the TH group. The urine volume per hour in the TH group were higher during cooling. After resuscitation, NGAL and CysC in the NH group were higher than in the TH group. Under the light microscope, compared with the TH group, the renal injury was prominent in the NH group. Conclusion: Mild hypothermia had a protection to renal ischemia reperfusion injury after resuscitation.

Screening of natural small molecule IDO-1 inhibitors with anti-tumor role / 药学学报

Fragments of the human indoleamine 2,3-dioxygenase 1 (IDO1) gene 5'-UTR (untranslated 1 245 bp region) promoters were amplified by PCR and cloned into pGL4.20 vector in the construction of reporter vector pGL4-IDO1-luc. A549 cells were transfected with the constructed plasmid and IDO1 inhibitor screening model was established with dual-luciferase reporter assay. Based on the model, we screened natural small molecules which could down-regulate the expression of IDO1 on tumor cells. The anti-tumor activities were examined by MTT, Western blotting and lactic dehydrogenase (LDH) release assays. Toosendanin (NS-180) down regulated the IDO1 expression and inhibited IFN-γ-induced STAT1 and STAT3 phosphorylation in A549 cells. Moreover, NS-180 significantly increased the cytotoxicity of co-cultured NK cells on A549 cells in LDH release assays. In summary, NS-180 is a novel and potent IDO1 inhibitor, which has an antitumor activity for cancer immunotherapies.

Advances in the research of inhibitors of enzymes of bacterial peptidoglycan biosynthesis / 药学学报

In recent years, owing to the abuse of antibiotics, the widespread of resistant bacterial strains became a serious threat to public health. This status demands development of new antibacterial agents with novel mechanisms of action. The reason for the limited new antibacterials is the small number of effective therapeutic targets, which cannot meet the current needs for the multiple drug-resistant treatment. Screening for new targets is the key step in the development of novel antibacterial agents. Peptidoglycan is the main component of the cell wall of bacteria, which is essential for survival of pathogenic bacteria. Within the biochemical pathway for peptidoglycan biosynthes is the Murligases, described in this review as highly potential targets for the development of new classes of antibacterial agents. This review provides an in-depth insight into the recent developments in the field of inhibitors of the Mur enzymes (MurA-F). Moreover, the reasons for the lack of candidate inhibitors and the challenges to overcome the hurdles are also discussed.

Construction of miR-15-a-loaded nano-complex and evaluation of its anti-prostate cancer effect in vitro / 中国药学杂志

OBJECTIVE: To synthesize cationic polymers of arginine-histidine (HRss) based on disulfide crosslink and construct novel nano-complex HRss/miR-15-a, then study its anti-prostate cancer effect in vitro. METHODS: 1H-NMR was used to characterize HRss2/miR-15-a. Zeta sizer was adopted to estimate the Zeta potential and particle size of the nano-complex. Gel electrophoresis was employed to determine the condensation capacity of HRssto miR-15-a. The cytotoxicity and transfection efficiency of HRss was evaluated using prostate cancer stem-like cells (RC-92a/hTERT). Transwell chambers were used to evaluate the influence of HRss/miR-15-a against the motility of RC-92a/hTERT. RESULTS: The RESULTS of cytotoxicity tests indicated that the carrier HRss2 had low toxicity in both normal cells and cancer cells, and the miR-15-a could be loaded in HRss2 to form stable nano-complex. The transfection efficiency and inhibited motility of HRss2/miR-15-a against RC-92a/hTERT were statistically higher than those of HRss1/miR-15-a and HRss3/miR-15-a. CONCLUSION: HRss may be useful for gene delivery, and HRss2, as the optimum polycationic carrier as shown by in vitro evaluation, has the potential to become a novel gene vector in the therapy of prostate cancer.

The whole-cell immobilization of D-hydantoinase-engineered Escherichia coli for D-CpHPG biosynthesis

Background: D-Hydroxyphenylglycine is considered to be an important chiral molecular building-block of antibiotic reagents such as pesticides, and β-lactam antibiotics. The process of its production is catalyzed by D-hydantoinase and D-carbamoylase in a two-step enzyme reaction. How to enhance the catalytic potential of the two enzymes is valuable for industrial application. In this investigation, an Escherichia coli strain genetically engineered with D-hydantoinase was immobilized by calcium alginate with certain adjuncts to evaluate the optimal condition for the biosynthesis of D-carbamoyl-p-hydroxyphenylglycine (D-CpHPG), the compound further be converted to D-hydroxyphenylglycine (D-HPG) by carbamoylase. Results: The optimal medium to produce D-CpHPG by whole-cell immobilization was a modified Luria-Bertani (LB) added with 3.0% (W/V) alginate, 1.5% (W/V) diatomite, 0.05% (W/V) CaCl2 and 1.00 mM MnCl2.The optimized diameter of immobilized beads for the whole-cell biosynthesis here was 2.60 mm. The maximized production rates of D-CpHPG were up to 76%, and the immobilized beads could be reused for 12 batches. Conclusions: This investigation not only provides an effective procedure for biological production of D-CpHPG, but gives an insight into the whole-cell immobilization technology.

Calpain-2 and calcineurin protein expression in right atrial appendages from patients underwent valve replacement with or without atrial fibrillation / 中华心血管病杂志

<p><b>OBJECTIVE</b>To investigate the relationship between the protein expression of calpain-2 and calcineurin (CaN) and atrial fibrillation (AF) in patient with valvular heart disease (VHD).</p><p><b>METHODS</b>A total of 40 patients who underwent valve replacement surgery in our hospital from March 2013 to March 2014, right atrial appendages were excised during operation and patients were divided into sinus rhythm (SR) group (n = 17) and AF group (n = 23). The protein expression of calpain-2 and the α-isoform of CaN catalytic subunit (CnA) in the right atrial appendages were determined by Western blot.</p><p><b>RESULTS</b>The protein levels of the full-length CnAa (60,000), the 45,000 fragment of CnAa without autoinhibitory domain, and calpain-2 were significantly upregulated in the AF group compared to the SR group (1.25 ± 0.51 vs. 0.76 ± 0.37, 1.08 ± 0.37 vs. 0.76 ± 0.25, and 0.82 ± 0.44 vs. 0.51 ± 0.19, respectively, all P < 0.05).</p><p><b>CONCLUSION</b>Activated calpain-2-CaN signal pathway might be involved in the pathogenesis of AF.</p>

Three-dimensional Pseudo-continuous Arterial Spin Label Non-contrast Enhanced Perfusion Imaging of Head and Neck Tumors with High-field MR System / 中国医学科学院学报

<p><b>OBJECTIVE</b>To evaluate the feasibility of three-dimensional pseudo-continuous arterial spin label (3D pCASL) non-contrast enhanced perfusion imaging applied to head and neck tumors in high-field MR and detect the effects of different postlabeling delay (PLD) time on image quality and the reliability of repeated measurements of tumor blood flow (BF) in different 3D pCASL groups.</p><p><b>METHODS</b>In this prospective study,all the 25 patients received neck 3D pCASL non-contrast enhanced perfusion examinations in a 3.0 T MR system by using an 8-channel head and neck joint coil. Conventional T1-weighted (TIWI) and T2-weighted imaging (T2WI) were performed firstly. Finally,three 3D pCASL with different PLD time [ASL1(PLD1=1525 ms),ASL2 (PLD2=2025 ms), ASL3(PLD3=2525 ms)] were acquired. Patients' perfusion-weighted images acquired from different 3D pCASL sequences underwent the analysis of signal to noise ratio (SNR) and contrast noise ratio (CNR) for tumors. Two observers performed the qualitative assessments on spiral artifacts and vascular artifacts of perfusion-weighted images from different 3D pCASL sequences. Blood flow (BF) of tumors from different 3D pCASL sequences were measured by the two observers respectively for the first time and by observer 2 for the second time.</p><p><b>RESULTS</b>Seventeen enrolled patients (age:50.1 ± 12.7 years,M/F=10:7) with histopathologic.</p><p><b>RESULTS</b>underwent the evaluation of image quality and measurements of BF values. The SNRs and CNRs of ASL1,ASL2, and ASL3 showed a descending trendency. SNRs (P=0.011) and CNRs (P=0.009) of ASL1 were significant higher than those of ASL3. There was no significant difference of scores of spiral artifacts among the three ASL groups (P=0.932). The scores of vascular artifacts of ASL1,ASL2,and ASL3 showed a descending trendency,also. And scores of ASL1 was significant higher than that of ASL3(P=0.000). The intraclass correlation coefficient (ICC) of intre-and intraobserver were high (ICC>0.9). Although the BF values of ASL1,ASL2, and ASL3 showed an ascending trendency,there was no significant difference among the three groups (P=0.977).</p><p><b>CONCLUSIONS</b>The 3D pCASL no-contrast enhanced perfusion MR imaging can be used for head and neck tumor. The image quality of perfusion weighted images and reliability of BF measurements were satisfied. The 3D pCASL series with PLD of 1525 ms and 2025 ms have better image quality than PLD of 2525 ms. And BF values do not show significant statistic difference among the three groups. Therefore, 3D pCASL series with PLD of 1525 ms and 2025 ms are more suitable for the perfusion imaging of head and neck tumors</p>

Comparison of the quality of different magnetic resonance image sequences of multiple myeloma / 中国医学科学院学报

<p><b>OBJECTIVE</b>To compare the image quality of T1WI fat phase,T1WI water phase, short time inversion recovery (STIR) sequence, and diffusion weighted imaging (DWI) sequence in the evaluation of multiple myeloma (MM).</p><p><b>METHODS</b>Totally 20MM patients were enrolled in this study. All patients underwent scanning at coronal T1WI fat phase, coronal T1WI water phase, coronal STIR sequence, and axial DWI sequence. The image quality of the four different sequences was evaluated. The image was divided into seven sections(head and neck, chest, abdomen, pelvis, thigh, leg, and foot), and the signal-to-noise ratio (SNR) of each section was measured at 7 segments (skull, spine, pelvis, humerus, femur, tibia and fibula and ribs) were measured. In addition, 20 active MM lesions were selected, and the contrast-to-noise ratio (CNR) of each scan sequence was calculated.</p><p><b>RESULTS</b>The average image quality scores of T1WI fat phase,T1WI water phase, STIR sequence, and DWI sequence were 4.19 ± 0.70,4.16 ± 0.73,3.89 ± 0.70, and 3.76 ± 0.68, respectively. The image quality at T1-fat phase and T1-water phase were significantly higher than those at STIR (P=0.000 and P=0.001) and DWI sequence (both P=0.000); however, there was no significant difference between T1-fat and T1-water phase (P=0.723)and between STIR and DWI sequence (P=0.167). The SNR of T1WI fat phase was significantly higher than those of the other three sequences (all P=0.000), and there was no significant difference among the other three sequences (all P>0.05). Although the CNR of DWI sequences was slightly higher than those of the other three sequences,there was no significant difference among all of them (all P>0.05).</p><p><b>CONCLUSION</b>Imaging at T1WI fat phase,T1WI water phase, STIR sequence, and DWI sequence has certain advantages,and they should be combined in the diagnosis of MM.</p>

Mesenteric lymph reperfusion after superior mesenteric artery occlusion shock exacerbates endotoxin translocation in brain

PURPOSE: To determine the role of mesenteric lymph reperfusion (MLR) on endotoxin translocation in brain to discuss the mechanism of brain injury subjected to superior mesenteric artery occlusion (SMAO) shock. METHODS: Twenty-four rats were randomly assigned to MLR, SMAO, MLR+SMAO and sham groups. MLR was performed by clamping the mesenteric lymph duct (MLD) for 1 h and then allowing reperfusion for 2 h in the MLR group; SMAO involved clamping the superior mesenteric artery (SMA) for 1 h, followed by reperfusion for 2 h in the SMAO group; occlusion of both the SMA and MLD for 1 h was followed by reperfusion for 2 h in the MLR+SMAO group rats. RESULTS: SMAO shock induced severe increased levels of the endotoxin, lipopolysaccharide receptor, lipopolysaccharide-binding protein, intercellular adhesion molecule-1 and tumor necrosis factor-α. Concurrently, MLR after SMAO shock further aggravates these deleterious effects. CONCLUSION: Mesenteric lymph reperfusion exacerbated the endotoxin translocation in brain; thereby increased inflammatory response occurred, suggesting that the intestinal lymph pathway plays an important role in the brain injury after superior mesenteric artery occlusion shock. .

Value of diffusion-weighted imaging in diagnosis of lymph node metastasis in patients with cervical cancer / 中国医学科学院学报

<p><b>OBJECTIVE</b>To investigate the value of diffusion-weighted imaging (DWI) in the differentiation of metastatic lymph nodes from non-metastatic lymph nodes in cervical cancer.</p><p><b>METHODS</b>In 65 patients who underwent lymph node dissection for cervical cancer, conventional MRI and DWI examinations were performed before surgery. Of the 1590 total dissected pelvic lymph nodes, 392 enlarged nodes with a short-axis diameter (S )of 5 mm or greater were included for further analysis. Each of the size-based criteria [i.e., S, long-axis diameter (L), and S/L ratio] and apparent diffusion coefficient(ADC)-based criteria (i.e., ADCmin, ADCmean, rADCmin, rADCmean) were compared between metastatic lymph nodes and non-metastatic lymph nodes.</p><p><b>RESULTS</b>There were statistically significant differences between metastatic and non-metastatic lymph nodes in S, L, S/L ratio, ADCmin, ADCmean, rADCmin, and rADCmean (all P<0.0001). The Az of the ADCmin (0.956) was greater than that of the other ADC-based criteria and all size-based criteria. Using ADCmin=759.0×10(-6) mm(2)/s, the sensitivity and specificity for differentiating metastatic from non-metastatic lymph nodes were 95.2% and 92.1%, respectively.</p><p><b>CONCLUSION</b>DWI, particularly ADCmin, is feasible for differentiating metastatic from non-metastatic pelvic lymph nodes in patients with cervical cancer.</p>