SMT-738: a novel small-molecule inhibitor of bacterial lipoprotein transport targeting Enterobacteriaceae.

Carbapenem-resistant Enterobacteriaceae (CREs) are described by the Centers for Disease Control as an urgent threat, and there is a critical need for new therapeutic agents able to treat infections caused by these pathogens. Herein, we describe the microbiological profile, the mechanism f action, and the in vitro safety as well as the pharmacokinetic (PK)/PD profile of SMT-738, a small molecule belonging to a new chemical class. SMT-738 is active against Enterobacterales [including multi-drug-resistant Escherichia coli with 90% of isolates having a minimum inhibitory concentration (MIC90) of 1 µg/mL and Klebsiella pneumoniae 2 µg/mL] and inactive against a broad panel of Gram-negative and Gram-positive pathogens. SMT-738 displays rapid bactericidal activity (2-4 h) and has a low propensity for resistance development (less than ~10-9). Characterization of resistant mutants following exposure to SMT-738 identified mutations within the lipoprotein transport complex (LolCDE), a clinically unexploited and essential bacterial molecular target in Gram-negative bacteria. SMT-738 has a promising in vitro toxicology profile. Furthermore, PK studies demonstrated that when dosed intravenously, SMT-738 maintained exposure levels across infection sites (bloodstream/urinary tract/lung). Proof-of-concept studies across multiple murine in vivo infection models (bloodstream/pneumonia/urinary tract) demonstrated that SMT-738 significantly reduced the bacterial burden compared to baseline and vehicle control. SMT-738 represents a promising novel drug candidate being developed to address clinically challenging serious life-threatening infections caused by highly resistant Enterobacteriaceae including CRE.

The value of MRCP in children with biliary symptomatology - an essential adjunct for safe cholecystectomy.

SUMMARY: Congenital abnormalities of the biliary system are a consideration in children with biliary symptomatology. The preoperative diagnosis rate is still not satisfactory, despite progresses made in imaging technology, with the potential of biliary tract injury if surgery is indicated. The double gallbladder is a rare developmental abnormality of the biliary tract with several anatomical variations. This abnormality was accurately delineated in a 7-year-old child by MRI/MRCP, allowing the ductal anatomy to be accurately identified and safe laparoscopic cholecystectomies to be performed.

[Current status and development trend of vascular compressive therapy].

As a non-invasive and safe physical therapy modality, compressive therapy plays an indispensable role in the treatment of vascular diseases and wounds. However, the concept of compressive therapy has not been widely adopted at present. And there are also problems such as non-standard treatment methods and inconsistent standards of pressure devices. Therefore, it is urgent to improve the standard system of compressive therapy, improve the level of diagnosis and treatment of related diseases, and promote the further development of compressive therapy.

[Current status of registered drug and vaccine pediatric clinical trials in China].

Objective: To evaluate the current status of the registered pediatric drug or vaccine clinical trials in China for the purpose of providing a reference for the development of pediatric clinical trials in China. Methods: We collected the data about registered pediatric clinical trials that were conducted from September 6, 2013(Mandatory registration start date) to September 6, 2019 (Cut-off date) at Chinadrugtrials.org.cn platform. The survey items included trial name and number, drug classification, sponsor's information, current trial status, completion status, etc. The clinical trials were categorized by drug group (includes chemical medicine, traditional Chinese medicine and natural medicine, biological products) and by vaccine group. Results: During the six years 349 pediatric clinical trials were registered on the platform, including 162 pediatric drug trials and 187 vaccine trials. The numbers of chemical drugs and biological products registered in 2018 were 23 and 11, respectively, the highest in the history. The number of pediatric clinical trials of traditional Chinese medicine and natural medicine was 11 in 2014, but from 2015 to 2018 only 2 to 4 trials were registered each year. The overall completion rates of the registered drug and vaccine clinical trials were 22.8% (37/162) and 41.7%(78/187), respectively. Only 42 international multicenter pediatric clinical trial projects were registered on the platform. The numbers of drug and vaccine phase Ⅰ clinical trials were 4 and 46, respectively. Thirty-six pediatric endocrine system agent clinical trials were carried out, with the largest number of all the drug categories registered on the platform. Conclusions: In recent years the number of registered pediatric drug and vaccine clinical trials increased in China. However, the number is still very limited. It is urgent to further promote the development of pediatric clinical trials.

Biological Characteristics and Genetic Diversity of Phomopsis asparagi, Causal Agent of Asparagus Stem Blight.

Asparagus stem blight is a regional disease. In the present study, we compared strains of Phomopsis asparagi from six different provinces to determine their biological characteristics and genetic diversity, differences in the pycnidium and conidium production, pathogenicity, and growth rate. Considerable differences were established in the pycnidium and conidium production among the P. asparagi strains from the six studied provinces. The largest pycnidium and conidium production had the strains from Fujian, followed by those from Hainan. The virulence of P. asparagi strains was significantly different but without a correlation with the geographical source of the strain. FJ2 had the highest virulence, followed by HN2, SD4, and SD5, whereas SD5 had the lowest virulence. The colony diameter and dry weight of the strains of asparagus stem blight fungus from the six provinces were substantially different. The colonies of HN1-5 had the largest diameters, whereas those of XT1-5, LT1-3, FJ1-5, and SX6 had smaller diameters. Four primers with good repeatability and strong specificity were selected from 100 intersimple sequence repeat (ISSR) primers. ISSR-PCR amplification was performed on 36 strains of asparagus stem blight fungus, and a large number of repeatable DNA fingerprints were obtained. Most of the amplified fragments were within 300 to 500 bp. In all, 69 total points, 64 multiple points, and 92.75% polymorphism points were established. The number of ISSR gene sites detected by four primers ranged from 14 to 20, with an average of 16 multiple sites. The copolymerization was divided into three groups: XT1-5, LT1-3, and FJ1-5, which were clustered into the first group; SD1-6, SX1-6, and HB1-6, clustered into the second group; and HN1-5 in the third group. The results of the cluster analysis revealed that the strains of the neighboring provinces had a nearer phylogenetic relationship than that between distant ones. Therefore, the system evolution of P. asparagi is related to the geographical distribution of its strains.

[The effects of continuous proton pump inhibitor therapy on small intestinal bacterial overgrowth in elderly].

Objective: Long-term proton pump inhibitor(PPI) therapy may increase the risk of small intestinal bacterial overgrowth(SIBO). Few studies on the effect of on-demand and continuous PPI therapy are available in elderly. To investigate the prevalence of SIBO and the effect of on-demand and continuous PPI therapy on SIBO in elderly. Methods: A total of 200 elderly outpatients admitted to Department of Gastroenterology at the Second Medical Center of PLA General Hospital were enrolled and divided into 3 groups: continuous PPI group, on-demand PPI group and control group. SIBO was diagnosed according to methane and hydrogen lactulose breath test (LBT).The prevalence of SIBO in the 3 groups was analyzed. Results: The prevalence of SIBO was 71.5% in 200 elderly. PPI therapy and diabetes mellitus (DM) were independent risk factors for SIBO. The prevalence of SIBO was 77.1% (108/140) in elderly who underwent long-term PPI therapy and 58.3% (35/60) in those without PPI therapy (P<0.01).The prevalence of SIBO was significantly higher in continuous PPI therapy group than that in on-demand PPI group and control group(88.6% vs. 65.7% and 58.3%, all P<0.01).However, no significant difference was found in the prevalence of SIBO between on-demand PPI group and control group (P>0.05). In elderly who underwent long-term PPI therapy, the prevalence of SIBO increased significantly if administration time was longer than 61 months. Conclusions: SIBO usually occurs in elderly patients who receive continuous PPI rather than on-demand use. If elderly require long-term PPI therapy, on demand administration is suggested as long as primary diseases are properly treated.

Circ_0000515 drives the progression of hepatocellular carcinoma by regulating MAPK10.

OBJECTIVE: To explore the expression pattern and clinical significance of circ_0000515 in hepatocellular carcinoma (HCC), as well as the molecular mechanism. PATIENTS AND METHODS: Fifty HCC patients were recruited, and their cancer tissues and adjacent normal ones were collected for detecting the differential expression of circ_0000515. The relationship between circ_0000515 and clinical parameters in HCC patients was analyzed. Circ_0000515 knockdown model was generated by lentivirus transfection in Hep3B and MHCC88H cells that were highly expressed with circ_0000515. Regulatory effects of circ_0000515 on phenotypes of Hep3B and MHCC88H cells were examined by Cell Counting Kit-8 (CCK-8) and transwell assay. Target gene of circ_0000515 was verified by Dual-Luciferase reporter assay, and its involvement in HCC progression was detected by rescue experiments. In vivo xenograft model was generated in nude mice aiming to elucidate the role of circ_0000515 in regulating HCC growth. RESULTS: Circ_0000515 was highly expressed in HCC tissues and cell lines. High level of circ_0000515 predicted advanced stage, high incidence of lymphatic metastasis, and low disease-free survival and overall survival in HCC. Knockdown of circ_0000515 attenuated proliferative and migratory abilities in Hep3B and MHCC88H cells. MAPK10, as the target gene binding circ_0000515, was negatively regulated by circ_0000515. Rescue experiments and in vivo xenograft model both indicated that circ_0000515 aggravated the malignant progression of HCC by targeting MAPK10. CONCLUSIONS: Circ_0000515 is upregulated in HCC tissues and cell lines. It can be used for predicting tumor staging, lymphatic metastasis, and prognosis in HCC. Circ_0000515 aggravates the malignant progression of HCC by downregulating MAPK10.

[A survey of knowledge regarding pediatric clinical trial among children at 8-18 years of age].

Objective: To investigate the knowledge regarding clinical research among children at 8-18 years of age. The survey results will form the basis for developing public education program for this population. Methods: The survey was conducted among children at 8-18 years of age using WeChat and spot investigation between January 2016 and January 2017. According to different developmental stages, the survey population was divided into four groups: age 8-10, 11-13, 14-15 and 16-18 years. The level of knowledge regarding clinical research was analyzed. Results: Totally 1 329 questionnaires were issued and 1 233 effective questionnaires were returned with a recovery rate of 92.8%. The overall awareness rate regarding clinical research was 32.8% (405/1 233) . It revealed that 282 (22.9%) individuals thought that clinical research was to treat people like experimental rats. When asked "who have the final decision on research participation", the percentages of those who chose oneself, parents or guardian and doctor were 44.6% (550/1 233), 74.2% (915/1 233) and 36.8% (454/1 233) respectively. When asked "If you want to participate a study, but your parents or guardian do not agree, what would you do?", 33.9% (418/1 233) of individuals will "give up". As to "If you do not want to participate a study, but your parents or guardian think you should, what would you do?", 51.3% (632/1 233) chose "listen to parents" and 28.8% (355/1 233) chose "refuse the suggestions of parents or guardian". As to "what are your greatest concerns of participating an investigation?" , 68.1% (840/1 233) chose "worry about added pain or discomfort". but 58.0% (715/1 233) thought if "doctors and nurses take good care of me" their "concerns will reduce" or "feel better to participate in the research?". 55.6% (686/1 233) and 49.3% (608/1 233) individuals responded that they will "participate in an research?" when they "know that other people also participate the research" and when they "know the details regarding what will happen after the enrollment". Conclusions: The knowledge level of clinical research among children aged 8-18 years were not high. It is very necessary to promote the public education of clinical research for this population and also very necessary to address their concern regarding the research.

Prediction of prostate cancer aggressiveness with a combination of radiomics and machine learning-based analysis of dynamic contrast-enhanced MRI.

AIM: To investigate whether the combination of radiomics and automatic machine learning-based classification of original images from multiphase dynamic contrast-enhanced (DCE)-magnetic resonance imaging (MRI) can predict prostate cancer (PCa) aggressiveness before biopsy. MATERIALS AND METHODS: Forty consecutive biopsy-confirmed PCa patients were included. Biopsy was performed within 4 weeks after the DCE-MRI examinations. According to the time-signal-intensity curve, lesion segmentation was performed on the first and on the strongest phase of the enhancement on the original DCE-MRI images, and 1,029 quantitative radiomics features were calculated automatically from each lesion, wherein there were three datasets available (Dataset-F, Dataset-S and Dataset-FS). The variance threshold method, select k-best method and least absolute shrinkage and selection operator (LASSO) algorithm were used to reduce the feature dimensions. Five machine learning approaches leveraging cross-validation were employed, and the clinical value of each model was evaluated by area under the receiver operating characteristic curve (AUC). Correlation analysis was performed between the features of the machine learning model that achieved the best classification performance and the Gleason score (GS) of the PCa lesion. RESULTS: Eight, four, and 16 features were selected as optimal subsets in Dataset-F, -S and -FS, respectively. Among all three datasets, logistic regression (LR)-based analysis with Dataset-FS had the highest predication efficacy (AUC=0.93). Ten features in Dataset-FS showed significantly positively correlation with GS. The model performance of Dataset-F was generally better than that in Dataset-S. CONCLUSIONS: A combination of radiomics and machine learning-analysis based analysis of the union of the first and strongest phases of original DCE-MRI images can predict PCa aggressiveness non-invasively, accurately, and automatically.

Distribution of particulate matter and ammonia and physicochemical properties of fine particulate matter in a layer house.

High concentrations of particulate matter (PM) and ammonia (NH3) in poultry houses have adverse effects on the health of workers and animals. The present study investigated the distribution of the PM in different size fractions and NH3, as well as analyzing the physicochemical properties of fine particulate matter (PM2.5) in an enclosed layer house. The detection was taken from 5:00 to 21:00 in every 2 h for a 7-d continuous monitoring using a DustTrak II model 8532 aerosol monitor for PM concentrations and a JK40-IV portable gas detector for NH3 concentrations. The concentrations of inhalable particulate matter (PM10), total suspended particles (TSP), and NH3 were significantly higher in the rear of the chicken house compared to the front (P < 0.05). The PM10, TSP, and NH3 concentrations inside the layer house were significantly higher than outside (P < 0.001). The concentrations of PM10 and TSP were both highest at the first feeding time at 7:00. The PM2.5/PM10, PM2.5/TSP, and PM10/TSP concentration ratios at 5:00 were highest with 0.84, 0.62, and 0.74, respectively. Airflow speed showed a significant correlation with other measured microclimatic variables. Organic carbon was the primary constituent of PM2.5 collected from the layer house. It was also observed that mass percentage of elements C and O were both the highest by energy spectrum diagrams of PM2.5. The ultrastructure of PM2.5 revealed that there were mineral particles derived from feed, feces, or the ground and that smoke polymers came from ambient air. In conclusion, air quality was better at the front than at the middle and rear of the layer house. Air quality outside was better than that inside the house. Chicken activities primarily caused the PM10 and TSP concentrations to increase in the chicken house. The main components of PM2.5 in the layer house were organic matter and minerals, which were mostly derived from feed, feces, and ground dust.

Dietary l-arginine supplementation improves semen quality and libido of boars under high ambient temperature.

l-Arginine is a nutritionally essential amino acid for spermatogenesis and plays versatile roles in animal health and can be utilized as a potential agent to improve reproductive performance of boars under high ambient temperature. The present study aimed to determine whether dietary l-arginine could alleviate heat stress-induced infertility in boars. In all, 20 boars (PIC 1040; 248.59±3.84 kg BW and 407.65±6.40 days of age) were selected and randomly assigned to four groups (group 0.0%, basal diet; group 0.6%, 0.8% or 1.0%, basal diet added with 0.6%, 0.8% or 1.0% l-arginine (wt:wt), respectively.) The four diets were made isonitrogenous by addition of appropriate amounts of l-alanine. Boars were pre-fed the corresponding experimental diet for 42 days. Then, the semen characteristics and libido were accessed for 6 weeks during the hot summer period (25.5° to 33.0°C). Results show that dietary l-arginine remarkably improved sperm motility, normality, total sperm number and effective total sperm number. Also, dietary l-arginine improved semen antioxidant capacity, such as decrease of malondialdehyde and 8-Hydroxy-2'-deoxyguanosine content in sperm (P<0.05), increase of the ratio of glutathione and oxidized glutathione, total antioxidant capacity, glutathione peroxidase and catalase activities in seminal plasma (P<0.05). Most of mitochondria contained intact ultrastructure in l-arginine-supplemented group which also accompany with higher ATP content than the 0.0% group. The boars fed 0.8% l-arginine show increased levels of estradiol-17ß and testosterone and exhibit improved libido performance than boars in the 0.0% group. Adding dietary l-arginine linearly increased (P=0.002) nitric oxide content (as l-arginine increased). The scrotal surface temperature in the 0.6%, 0.8% and 1.0% group were decreased by 0.9°C, 0.9°C and 0.4°C, respectively, compared with the 0.0% group. l-Arginine levels caused linear effect on semen quality and antioxidant capacity, also caused quadratic effect on libido performance. During the hot summer months, the predicted optimal l-arginine levels for best semen quality and antioxidant capacity was 0.8% to 1.0% and for best libido performance was 0.8%. It can be concluded that l-arginine can be used as an effective agent to alleviate heat stress-induced infertility of boar, and that 0.8% to 1.0% can be considered as the optimum dosage.

Danshen (Salvia miltiorrhiza) protects ovariectomized rats fed with high-saturated fat-sucrose diet from bone loss.

Dietary patterns may interfere with the efficacy of herbal intervention. Our results demonstrated the protective effects of Salvia miltiorrhiza aqueous extract (SMA) on bone metabolism were influenced by levels of dietary fat and sucrose in ovariectomized (OVX) rats through its actions on attenuating lipid deposition and oxidative stress in rats. INTRODUCTION: Salvia miltiorrhiza (SM), also known as Danshen, has been tested as an osteoporosis treatment in a series of small, short human trials that generally report improvements in bone property. However, dietary patterns may interfere with the effects of herbal intervention. We hypothesized that dietary fat and sucrose levels could influence the effects of SM supplementation on bone in estrogen-deficient animals. METHODS: Six-month-old Sprague-Dawley sham or OVX rats were fed either a low-saturated fat-sucrose (LFS, a diet that was similar in composition to normal rat chow) or a high-fat-sucrose (HFS) diet and OVX rats were treated (8 rats/group) with SM aqueous extract (SMA, 600 mg/kg/day), 17ß-estradiol (1 mg/kg/day), or vehicle for 12 weeks. RESULTS: SMA significantly improved bone properties as revealed by the increase in trabecular bone mineral density and decrease in trabecular separation at proximal metaphysis of the tibia (PT) in HFS-fed OVX rats, but not in LFS-fed OVX rats. SMA greatly reduced lipid deposition and malondialdehyde levels, improved the activities of superoxide dismutase, catalase, and glutathione peroxidase in the livers of HFS-fed OVX rats. SMA could directly improve the proliferation and differentiation in vitro in an H2O2-induced preosteoblast cell model by attenuating cellular reactive oxygen species levels. CONCLUSIONS: The protective effects of SMA on bone metabolism were influenced by dietary fat and sucrose levels in OVX rats. The ability of SMA to reduce bone loss in HFS-fed OVX rats was associated with the attenuation of lipid deposition and oxidative stress levels.

[The expression and role of PLUNC, TLR2 and NF-κB in nasal polyps].

Objective:To investigate the expression of palate, lung, nasal epithelium clone (PLUNC), Tolllike receptor 2 (TLR-2) and nuclear factor-Kappa B (NF-κB) in nasal polyps tissues and normal inferior turbinate mucosa. To analysethe correlation of their expression and to provide a new treatment of nasal polyps.Method:The specimens were divided into two groups: nasal polyps tissues group (n = 46) and normal inferior turbinate mucosa group (n = 19). EOS and others inflammatory cells was detected by HE staining. performing immunohistochemistry, we investigated the expression and distribution of PLUNC, TLR2 and NF-κB. Meanwhile we evaluated the positive expression and correlation of PLUNC, TLR2 and NF-κB between experimental group and control group. All data were processed by using SPSS 21.0 software.Result:EOS infiltration was significantly higher than the control group (P< 0.05). The expression level of PLUNC in experimental group is significantly lower, there is a statistical significance (P< 0. 05). The expression of TLR2 and NF-κB in experimental group is obviously higher than the control group, with statistical significance (P< 0.05). Spearman correlation analysia showed that PLUNC in experimental group is negatively correlated with TLR2 and NF-κB (r= －0.675, r= －0.550, P< 0.05). TLR2 is positively correlated with NF-κB (r= 0.540, P< 0.05). EOS infiltration degree positive correlation with TLR2 and NF-κB exist (r= 0.417, r= 0.470, P< 0.05), degree negative correlation with PLUNC exist (r= －0.859, P< 0.05).Conclusion:PLUNC expression in nasal polyps is lower than the normal inferior turbinate group. TLR2 and NF-κB expression in nasal polyps are higher than the normal inferior turbinate group.suggesting that the formation of nasal nolyps may be associated with lower natural immunity and the existing of infectious agents.

[Research advances in drug-induced autoimmune hepatitis].

Drug induced autoimmune hepatitis (DIAIH) refers to the liver injury mediated by drug-induced autoimmune reaction. Since it has similar clinical features as idiopathic autoimmune hepatitis, it is often difficult to make differential diagnosis in clinical practice. A deep understanding of the development, pathogenesis, related drugs, risk factors, and clinical and histological features of DIAIH helps with the correct diagnosis and treatment of DIAIH.

Association between IL18-607C/A and -137G/C polymorphisms and susceptibility to non-small cell lung cancer in a Chinese population.

Lung cancer is one of the main causes of cancer-related mortality in males and females worldwide. A pleiotropic effect has been observed in the interleukin 18 gene (IL18); its effects include the activation of natural killer cell cytotoxicity and the promotion of the Th1 immune response through the alteration of the expression of interferon-γ and TNF-α in humans. IL18 is therefore involved in the elimination of tumor cells in the human body. We recruited 357 patients with non-small cell lung cancer (NSCLC) and 414 controls to evaluate the correlation between two genetic variations (IL18-607C/A and IL18-137G/C) and the pathogenesis of NSCLC. We used polymerase chain reaction-restriction fragment length polymorphism to genotype IL18-607C/A and IL18-137G/C. Statistical analysis revealed that individuals harboring the AA genotype of IL18-607C/A had an increased risk of NSCLC compared to those harboring the CC genotype (OR = 2.20, 95%CI = 1.30-3.74). Individuals expressing the A allele of IL18-607C/A had an elevated risk of developing NSCLC compared to those expressing the C allele (OR = 1.31, 95%CI = 1.06-1.62). In summary, our analysis shows that the IL18-607C/A genetic variation is related to the risk of NSCLC, whereas the IL18-137G/C variation is not. Therefore, the IL18-607C/A variation is related to the pathogenesis of NSCLC in the Chinese population studied.

Pattern of GHR mRNA expression and body growth in the S2 line of sex-linked dwarf chickens.

Sex-linked dwarf (SLD) chickens have been widely used in cross breeding of broilers and laying hens. To study the molecular mechanisms underlying growth hormone receptor (GHR) in SLD chickens, the expression profiles of GHR were measured in three growth related tissues (liver, breast, and thigh) in male and female S2 SLD chickens at seven growth stages (1 day, 3 weeks, 7 weeks, 9 weeks, 11 weeks, 13 weeks, and 15 weeks). Growth curves of body weight were fitted using logistic and Gompertz models. The results show that the inflexion week and inflexion weight in male chickens was earlier than in female chickens. Regarding the expression profiles of GHR, there was no significant difference between tissues at hatching. The expression peaked at 7 weeks and dropped by degrees in muscle tissue; hepatic expression increased with age and was positively correlated with body weight. Taken together, these results would provide a basis for further study on the molecular mechanisms underlying GHR regulation in SLD chickens.

[Preliminary application of amide proton transfer imaging signal in acute ischemic stroke].

OBJECTIVE: To apply amide proton transfer magnetic resonance imaging (APT-MRI) technique to acute ischemic stroke, and to discuss clinical values of the APT-MRI main parameter - MTRasym(3.5 ppm). METHODS: A total of 18 emergency admitted patients, with acute ischemic stroke from Beijing Hospital, were recruited from March to November 2015. Eventually, 18 patients (male 14, female 4, average age 72 years old, age ranged from 52 to 92 years, symptom onset ≤24 hours, 2 patients≤ 6 hours) were included in this study. All patients underwent MR scanning on the brain at 3.0 Tesla. Besides the conventional scans for stroke, the APT sequence (saturation time 0.8 s, saturation power 2 µT) was performed. APT weighted (APTW) images were calculated using magnetization transfer ratio asymmetry at 3.5 ppm with respect to water. MRI signals in APTW, diffusion weighted images (DWI) and fluid attenuated iversion recovery (FLAIR) were visually evaluated. Shapiro-Wilk tests were performed to find out the distribution of MTRasym(3.5 ppm) in the whole sample, infarction regions, and normal appearing white matter (NAWMs), respectively. Detrended normal P-P plots were also used to evaluate its normality. Paired-t test and two-sample t test were applied to compare the mean MTRasym(3.5 ppm) of infarction regions with that of contra lateral NAWMs. RESULTS: (1) High signal intensity was observed in DWI and FLAIR in all 18 patients. However, signal intensity was somewhat different in APTW. 13 patients were found decreased APT effect, and 5 patients were with equal APT effect in infarction regions. In NAWMs, 14 patients were found equal APT effect, and 4 patients were with decreased APT effect. (2) MTRasym(3.5 ppm)s were proven, with Shapiro-Wilk test, to distribute normally within the whole sample (W=0.964, P=0.288), infarction regions (W=0.962, P=0.645), and NAWMs(W=0.929, P=0.187). However, its normality was not so satisfactory due to greater deviations (absolute value>0.06) of some cases in detrended normal P-P plots. (3) Paired-t test analysis showed that MTRasym(3.5 ppm) in infarction regions (-0.035%±1.020%) was significantly lower than that in NAWMs (0.386%±0.790%) (t=-2.273, P=0.036). However, there was no statistically significant difference between infarction regions and NAWMs when two sample t-test was performed (t=-1.386, P=0.175). CONCLUSION: MTRasym(3.5 ppm) can be used to evaluate acute ischemic stroke with a broad future scope in clinical.

Sensitive determinations of Cu, Pb, Cd, and Cr elements in aqueous solutions using chemical replacement combined with surface-enhanced laser-induced breakdown spectroscopy.

In this study, chemical replacement combined with surface-enhanced laser-induced breakdown spectroscopy (CR-SENLIBS) was for the first time applied to improve the detection sensitivities of trace heavy metal elements in aqueous solutions. Utilizing chemical replacement effect, heavy metal ions in aqueous solution were enriched on the magnesium alloy surface as a solid replacement layer through reacting with the high chemical activity metallic magnesium (Mg) within 1 minute. Unitary and mixed solutions with Cu, Pb, Cd, and Cr elements were prepared to construct calibration curves, respectively. The CR-SENLIBS showed a much better detection sensitivity and accuracy for both unitary and mixed solutions. The coefficients of determination R2 of the calibration curves were above 0.96, and the LoDs were of the same order of magnitude, i.e., in the range of 0.016-0.386 µg/mL for the unitary solution, and in the range of 0.025-0.420 µg/mL for the mixed solution. These results show that CR-SENLIBS is a feasible method for improving the detection sensitivity of trace element in liquid sample, which definitely provides a way for wider application of LIBS in water quality monitoring.

[The effect and injury to the airways of different sputum aspiration pressure in a rat model of mucus hypersecretion].

OBJECTIVE: To explore the optimal pressure of sputum aspiration to ensure the effectiveness and safety of clinical operation. METHODS: We established a rabbit model of airway mucus hypersecretion by aerosol acrolein inhalation, and the animals were divided into 4 groups randomly with different sputum aspiration pressure as follows: group A -75 mmHg (1 mmHg=0.133 kPa), group B -150 mmHg, group C -225 mmHg, group D -300 mmHg. Sputum aspiration efficiency and tracheal mucosal damage degree were evaluated by sputum volume, oxygen saturation changes, the pathological sections of tracheal mucosa and the expressions of IL-1ß and TNF-α in airway secretion. RESULTS: The sputum suction volume of group A, B, C, D were (2.72±0.24), (4.81±0.32), (5.03±0.37) and (6.29±0.51) ml, respectively, which was significantly higher in group D, but lower in group A, as compared to other groups (P<0.05). There were no significant differences between B and C groups. The maximal SpO2 decrease of C and D groups [(18.1±5.2)% and(32.4±8.4)%]were significantly higher than those in A and B groups [(4.4±1.7)% and (6.3±2.9)%], and group D was significantly more than group C, and the difference was statistically significant (P<0.05). There were no significant differences between A and B groups. HE staining of tracheal mucosa in C and D groups showed that the inflammatory cell infiltration and mucosal damage were more serious than A and B groups, but the airway mucosal damage of group A was the least. CONCLUSION: The pressure of -150 mmHg was more effective with high oxygen saturation and less airway injury, which may be suitable for clinical sputum aspiration.

Application of retrograde dissection method for isolation of bone marrow cells from rat femurs and tibiae.

Currently, there is no practical and efficient method for the isolation of bone marrow cells (BMCs) from rat femurs and tibiae. Here, we attempted to develop a rapid, simple, effective, and non-contaminating method for the isolation of BMCs from rat femurs and tibiae. Rat femurs and tibiae were dissected from the ankle to the hip joint; subsequently, a three-step "locate-slide-twist" procedure was performed using scissors and forceps to remove the femurs and tibiae completely, from the surrounding musculature. The bones were flushed with phosphate-buffered saline to harvest BMCs. The femurs and tibiae were dissected in 1.8 ± 0.6 min, and the BMC suspension preparation time was 13.1 ± 2.3 min. The bone marrow cavities did not incur any fractures or injuries during the isolation. Culture of harvested BMCs for 72 h led to a significant increase in cell number from 4.4 ± 0.3 x 106 to 6.9 ± 0.7 x 10(6) (P < 0.01) with no significant decrease in viability (98.1 ± 0.6% vs 96.2 ± 1.1%; P > 0.05). Microscopic examination of the isolated BMCs after the 72-h incubation period revealed the no-microbial or muscle cell contamination. Furthermore, flow cytometry revealed that cultured BMCs (72-h culture) grew well. Here, we have reported a rapid, simple, effective, and non-contaminating method for the isolation of BMCs from rat femurs and tibiae by using retrograde dissection. This method can be used to harvest a large number of viable BMCs without the risk of contamination from muscle and connective tissues.