[Similarities and differences of myocardial metabolic characteristics between HFpEF and HFrEF mice based on LC-MS/MS metabolomics]

Objective: To reveal the similarities and differences in myocardial metabolic characteristics between heart failure with preserved ejection fraction (HFpEF) and heart failure with reduced ejection fraction (HFrEF) mice using metabolomics. Methods: The experimental mice were divided into 4 groups, including control, HFpEF, sham and HFrEF groups (10 mice in each group). High fat diet and Nω-nitroarginine methyl ester hydrochloride (L-NAME) were applied to construct a"two-hit"HFpEF mouse model. Transverse aortic constriction (TAC) surgery was used to construct the HFrEF mouse model. The differential expression of metabolites in the myocardium of HFpEF and HFrEF mice was detected by untargeted metabolomics (UHPLC-QE-MS). Variable importance in projection>1 and P<0.05 were used as criteria to screen and classify the differentially expressed metabolites between the mice models. KEGG functional enrichment and pathway impact analysis demonstrated significantly altered metabolic pathways in both HFpEF and HFrEF mice. Results: One hundred and nine differentially expressed metabolites were detected in HFpEF mice, and 270 differentially expressed metabolites were detected in HFrEF mice. Compared with the control group, the most significantly changed metabolite in HFpEF mice was glycerophospholipids, while HFrEF mice presented with the largest proportion of carboxylic acids and their derivatives. KEGG enrichment and pathway impact analysis showed that the differentially expressed metabolites in HFpEF mice were mainly enriched in pathways such as biosynthesis of unsaturated fatty acids, ether lipid metabolism, amino sugar and nucleotide sugar metabolism, glycerophospholipid metabolism, arachidonic acid metabolism and arginine and proline metabolism. The differentially expressed metabolites in HFrEF mice were mainly enriched in arginine and proline metabolism, glycine, serine and threonine metabolism, pantothenate and CoA biosynthesis, glycerophospholipid metabolism, nicotinate and nicotinamide metabolism and arachidonic acid metabolism, etc. Conclusions: HFpEF mice have a significantly different myocardial metabolite expression profile compared with HFrEF mice. In addition, biosynthesis of unsaturated fatty acids, arachidonic acid metabolism, glycerophospholipid metabolism and arginine and proline metabolism are significantly altered in both HFpEF and HFrEF mice, suggesting that these metabolic pathways may play an important role in disease progression in both types of heart failure.

[Clinical study on the relationship between the exosomes in bronchoalveolar lavage fluid and plasma and the severity of lung injury and outcome in early acute respiratory distress syndrome patients]

Objective: To investigate the relationship between the levels of exosomes in bronchoalveolar lavage fluid (BALF) and plasma and the severity of lung injury and its outcome in patients with acute respiratory distress syndrome (ARDS). Methods: Patients who were admitted to the Department of Critical Care Medicine, Zhongda Hospital Affiliated to Southeast University and received invasive mechanical ventilation were selected from August 2020 to April 2021, and they were divided into ARDS group and non-ARDS group. Finally, 33 ARDS patients were included, including 18 males and 15 females, aged (65.5±15.5) years; 10 non-ARDS patients, 8 males and 2 females, aged (57.2±15.3) years. The BALF and plasma of the two groups of patients were collected within 24 hours after enrollment, and the total exosomes of the samples were collected by ultracentrifugation. Nanoparticle tracking analysis (NTA) was used to detect and compare the differences in exosome content between the two groups. Correlation of content with the severity and prognosis of lung injury in ARDS patients. Results: There was no significant difference in gender and age between ARDS group and non-ARDS group (both P>0.05). The exosome in plasma of ARDS group was significantly higher than that of non-ARDS group [(25.3±1.2)/ml vs (24.2±1.6)/ml, P=0.031], while the exosomes in BALF of ARDS group was also higher than that of non-ARDS group [(26.5±1.6)/ml vs (24.6±1.1)/ml, P=0.001]. The exosomes in BALF of patients with ARDS caused by intrapulmonary causes was higher than that in ARDS group caused by extrapulmonary causes [(26.9±1.5)/ml vs (25.2±0.9)/ml, P=0.01], and the infection caused by bacterial shows that the highest exosome level in BALF. The exosomes in the BALF of the mild ARDS group was significantly lower than that of the severe ARDS group [(25.7±1.3)/ml vs (27.2±1.5)/ml, P=0.038]; the exosomes in BALF of ARDS patients was negatively correlated with P/F ratio (r=-0.38, P=0.03); and it was positively correlated with Murray lung injury score (r=0.47, P=0.01). However, the static compliance levels, length of hospital stay, duration of mechanical ventilation, and 28-day outcome were not associated with the exosomes in BALF. Conclusion: Compared with non-ARDS patients, ARDS patients have significantly higher levels of exosomes in BALF and plasma, there is a certain correlation between exosomes derived from BALF and the severity of lung injury in ARDS.

[An area under curve-based nomogram to predicts vancomycin-associated nephrotoxicity in critically ill patients: a retrospective cohort study]

Objective: To develop an area under curve (AUC)-based nomogram to predict vancomycin-associated nephrotoxicity in critically ill patients. Methods: This retrospective cohort study included adult patients treated with vancomycin in the intensive care unit at a tertiary teaching hospital from January 2015 to December 2017. Baseline clinical characteristics before vancomycin treatment and pharmacokinetic parameters were collected to establish a prediction model of nephrotoxicity. Univariate analysis was used to screen variables, and multivariate logistic regression analysis was used to establish the prediction model and nomogram. Results: A total of 159 patients met the inclusion criteria, sixty-four were included in the final analysis. Sixteen patients (25%, 16/64) developed vancomycin-associated nephrotoxicity. The following variables were incorporated into the prediction model: vancomycin AUC, estimated glomerular filtration rate (GFR), and combined nephrotoxic drugs. The following equation was established to calculate the probability of nephrotoxicity: logit (P)=-4.83+0.009×AUC-2.87×1 (if GFR>60 ml/min)+2.53×1 (if number of combined nephrotoxic drugs≥2). A nomogram was generated based on the equation. The receiver-operating characteristic curve demonstrated that the AUC of the prediction model was 0.927 (95%CI 0.851-1.000). The cut-off value of the probability of nephrotoxicity was 26.48%. The sensitivity and specificity were 87.5% and 87.5% respectively. Conclusion: The incidence of vancomycin-associated nephrotoxicity is high. The AUC-based nomogram can effectively predict vancomycin-associated nephrotoxicity in critically ill patients.

[The implementation of hour-1 bundle for sepsis in medical staff]

To determine the physicians'compliance of hour-1 bundle for sepsis. A management system of hour-1 bundle for sepsis was established. The clinical data of 286 sepsis patients were collected, who were classified into 3 months before the bundle (control group), 9 months during process (observation group) and 3 months after bundle (study group). The compliance of hour-1 bundle implementation was compared in three groups. The results showed that with the application and implementation of the management system, the compliance of hour-1 bundle for sepsis in the control group, observation group and study group was 58.3%(28/48), 69.1%(105/152) and 88.4%(76/86) respectively (χ²=7.053,P=0.029). The 28 day mortality in sepsis patients was 41.7%(20/48), 34.9%(53/152) and 23.3%(20/86) respectively (χ²=5.576,P=0.062).The management system of hour-1 bundle for sepsis can effectively improve the physicians' compliance.

[Preliminary application of postoperative fast track transfer to intensive care unit for the geriatric hip fractures under enhanced recovery after surgery]

Objective: To develop a fast track transfer to intensive care unit (ICU) for the perioperative high-risk elderly patients after hip fracture surgery and analyze the preliminary clinical effect of the application. Methods: From January 2014 to December 2017, before the application of postoperative fast track transfer to ICU, the clinical data of 195 elderly patients with hip fracture were included in a retrospective analysis. Among 195 hip fracture patients, 18 were transferred to ICU post operation (non-fast track group). Multivariate logistic regression analysis was applied to investigate relevant risk factors for transferring to ICU after hip fracture surgery. Based on risk factors acquired from the analysis and clinical experience, the fast track transfer to ICU for the perioperative high-risk elderly patients after hip fracture surgery was constructed according to the preliminary and experiential criteria. From January 2018 to December 2019, the clinical data of 70 patients (fast track group) who were transferred to ICU after hip fracture surgery through the fast track were collected and compared with non-fast track group. Results: Multivariate regression analysis revealed that American Society of Anesthesiologists classification(≥Ⅲ) (OR=4.260, 95%CI:1.157-15.683, P=0.029), pre-hospital stage (≥48 h) (OR=4.301, 95%CI:1.212-15.266, P=0.024), hemoglobin concentration at admission(<90 g/L) (OR=7.979, 95%CI:1.936-32.889, P=0.004), coronary heart disease as one comorbidity(OR=6.063, 95%CI:1.695-21.693, P=0.006) were independent risk factors for transferring to ICU after hip fracture surgery. There were no significant difference in gender, age, fracture type, hemoglobin concentration at admission and time of pre-hospital stage between the non-fast track group and fast track group(all P>0.05). However, the number of comorbidities in the fast track group was significantly higher than that in the non-fast track group (Z=-1.995, P=0.046). The time to surgery, postoperative hospital stay, and length of hospital stay in fast track group were all significantly less than those in non-fast track group (Z=-2.121, -2.726, -3.130, all P<0.05). Also, there were fewer medical consultations needed and fewer patients who stayed in ICU more than or equal to 2 nights in fast track group than that in non-fast track group(all P<0.05). There were no significant difference in the rate of patients who transferred from the general ward to ICU after transferring from ICU to the general ward, the proportion of patients who received more than or equal to 4 departments, operation time, hospitalization expense, mortality during hospitalization, 30-day mortality and 90-day mortality after operation between the two groups(all P>0.05). Conclusions: The fast track constructed in this study can reduce time to surgery, postoperative hospitalization stay and length of hospitalization stay for the perioperative high-risk elderly patients with hip fractures and is a specific clinical application of eras concept based on multidisciplinary team.

[Vertical supraumbilical incision versus left lower oblique incision for specimen retrieval during laparoscopic rectal surgery]

Objective: To compared the short-term surgical outcomes of the vertical supraumbilical incision with the left lower oblique incision for specimen retrieval in laparoscopic resection for rectal cancer. Methods: A retrospective cohort study was performed. Inclusion criteria: (1) rectal cancer confirmed by colonoscopy and pathological examination; (2) undergoing the operation for the first time; (3) laparoscopic rectal surgery performed by the same surgeon team; (4) age of > 18 years and < 76 years old. According to above criteria, clinical data of 178 consecutive patients scheduled for laparoscopic surgery for rectal cancer at Department of Gastrointestinal Surgery of Renji Hospital between March 2015 and December 2017 were collected. Based on incision site of the mini-laparotomy, patients were classified to the vertical supraumbilical incision group (n=75) and the left lower oblique incision group (n=103). There were no significant differences in baseline data, such as age, gender, body mass index (BMI), tumor diameter, preoperative carcinoembryonic antigen (CEA) level, score of American Society of Anesthesiologists, TNM stage, between the two groups (all P>0.05). Perioperative variables and follow-up data were compared between two groups. Results: Between the vertical supraumbilical incision group and the left lower oblique incision group, the operation time [(131.7±3.7) minutes vs. (138.5±3.5) minutes], operative bleeding volume [(138.9±11.5) ml vs. (154.3±10.3) ml], length of auxiliary incision [(4.0±0.1) cm vs. (4.0±0.1) cm], and distance from anastomosis to dentate line [(3.8±0.1) cm vs. (4.2±0.1) cm] were not significantly different (all P>0.05). As compared to the left lower oblique incision group, patients in vertical supraumbilical incision group had earlier flatus [(62.7±2.3) hours vs. (69.2±1.7) hours, t=2.282, P=0.023], earlier ambulation [(41.9±1.8) hours vs. (46.78±1.42) hours, t=2.131, P=0.032], lower pain VAS scores at postoperative 24 hours (2.0±0.1 vs. 2.4±0.1, t=2.172, P=0.032) and 48 hours (2.7±0.1 vs. 3.0±0.1, P<0.05), and lower incidence of postoperative incisional hernia [6.7% (5/75) vs. 9.7% (10/103), χ(2)=3.942, P=0.042]. However, the postoperative fluids intake time, hospitalization days, pain VAS scores at postoperative 12 hours and postoperative complications (wound infection, anastomotic leakage, urinary retention, intestinal obstruction) were not significantly different between the two groups (all P>0.05). Conclusion: The vertical supraumbilical incision in laparoscopic resection for rectal cancer can reduce the degree of postoperative pain, facilitate early recovery of intestinal function and decrease the incidence of incisional hernia.

[Systematic evaluation of neuromuscular blocking agents on prognosis of patients with moderate to severe acute respiratory distress syndrome]

Objective: To evaluate the prognostic impact of neuromuscular blocking agents (NMBA) on patients with acute respiratory distress syndrome (ARDS). Method: Online search of MEDLINE, Embase, Web of Science, CNKI, CBM and other Chinese databases for randomized controlled trials (RCTs) of NMBA in patients with ARDS from January 1994 to June 2019 was done, and literature was selected according to inclusion and exclusion criteria. The patients were divided into NMBA group and non-NMBA group according to whether NMBA was adopted or not. The prognostic indicators (ICU mortality, 28 d mortality, 90 d mortality) and NMBA-related complications (ICU acquired muscle weakness, barometric injury, pneumothorax) of the patients in the two groups were mainly analyzed. Meta-analysis of the data was performed using RevMan 5.0 software. Results: A total of 6 RCTs were included, and 1 502 patients were enrolled, including 761 in the NMBA group and 741 in the no-NMBA group. The 90-day mortality in the NMBA group and no-NMBA group were 38.8% and 42.6%, OR=0.87 (95%CI: 0.70-1.07, P=0.190); the 28-day mortality rates were 32.5% and 36.5%, OR=0.71 (95%CI: 0.45-1.11, P=0.130); ICU mortality rates were 31.8% and 43.8%, OR=0.60 (95%CI: 0.41-0.88, P=0.009). Conclusion: NMBA can reduce the ICU mortality of moderate to severe ARDS patients, but not reduce 28-day and 90-day mortality.

[The influencing factors achieving target vancomycin trough level in critically ill patients]

Objective: To assess the rate achieving the target vancomycin trough level (VTL) and its influencing factors in critically ill patients. Methods: The retrospective observational study recruited adult patients treated with intravenous vancomycin in the intensive care unit (ICU) at Zhongda Hospital from January 2015 to December 2017. Serum VTL was tested at steady state. Patients' demographics, the sites of infection, microbial culture results, the severity of illness, laboratory data and vancomycin regimen were obtained at the baseline. The rate achieving target VTL (15-20 mg/L) was analyzed based on renal function. Linear regression was performed to determine the influencing factors of VTL. Results: A total of 85 patients were enrolled, among whom only 23.5% (20/85) achieved the target VTL. In patients with normal renal function, the achieving rate was only 11.4% (4/35), and 80.0% (28/35) was lower than the target trough level multiple linear regression analysis showed that procalcitonin (PCT), estimated glomerular filtration rate (eGFR) and acute physiology and chronic health disease classification system Ⅱ (APACHE Ⅱ) score were independent factors associated with VTL. Conclusion: Achieving target VTL in critically ill patients is not satisfactory. Further study to optimize the administration is needed to facilitate prompt attainment of target VTL.

[A clinical study of haploidentical hematopoietic stem cell transplantation in the treatment of pediatric patients with acquired severe aplastic anemia: single center experience]

目的

探讨单倍型造血干细胞移植（haplo-HSCT）治疗儿童获得性重型再生障碍性贫血（SAA）的疗效。

方法

回顾性分析2011年12月1日至2017年12月1日接受haplo-HSCT的59例SAA患者。

结果

①全部59例SAA患儿中男37例、女22例，中位年龄4.5（1.2~14.8）岁，中位体重43（12~80）kg；SAA-Ⅰ型47例，SAA-Ⅱ型12例，26例为极重型再生障碍性贫血（VSAA）；首次移植56例，二次移植3例。②预处理选用白消安+环磷酰胺+抗胸腺细胞球蛋白（ATG）方案或白消安+氟达拉滨+环磷酰胺+ATG方案；采用环孢素A（CsA）+霉酚酸酯+甲氨蝶呤方案预防急性GVHD；回输单个核细胞中位数为15.60（7.74~21.04）×10⁸/kg，CD34⁺细胞中位数为4.86（3.74~7.14）×10⁶/kg。③全部59例患儿均获得中性粒细胞和血小板植入。中性粒细胞植入中位时间为13（10~19）d，血小板植入中位时间为19（9~62）d。④Ⅰ~Ⅱ、Ⅲ/Ⅳ度急性GVHD发生率分别为45.76%（27/59）、13.56%（8/59），慢性GVHD发生率为8.47%（5/59）。巨细胞病毒血症发生率为59.32%（35/59）、EB病毒血症发生率为28.81%（17/59）。⑤中位随访时间30（8~80）个月，57例无病存活，2例死亡（均死于GVHD），5年总生存率、无失败生存率均为（96.4±2.5）%。

结论

haplo-HSCT是儿童SAA疗效较好的治疗方法。

[Echocardiographic diagnosis of infracardiac total anomalous pulmonary venous connection]

OBJECTIVE

To investigate the clinical usefulness of echocardiography in the diagnosis of infracardiac total anomalous pulmonary venous connection (ITAPVC) in neonates and infants.

METHODS

Retrospective analysis on 8 patients with ITAPVC was performed using echocardiography between April 2006 and December 2016. There were 4 boys and 4 girls with a mean age of 79.8 days (ranging from 15 to 195 days). A combined scanning via parasternal, subcostal and apical acoustic windows had been employed to diagnose ITAPVC and to trace the course and site of the anomalous pulmonary venous drainage, and to confirm the direction of the inter-atrial shunt and enlargement of right atrium and right ventricle.

RESULTS

Of the 8 patients who received echocardiography, ITAPVC was diagnosed in 7 patients. Mis-diagnosis by echocardiography was encountered in one patient. The diagnosis by echocardiography was compatible with the operative findings in 5 patients receiving surgery and with the results of multislice computed tomography in 6 patients. The diagnostic accuracy rate of ITAPVC was 87.5%. The indirect signs obtained from echocardiogram was coexistence of a small malformed, triangle-shaped left atrium and right to left shunting at atrial level with dilatation and tortuousness of portal vein or hepatic vein and abundant blood flow in liver. The direct signs was total pulmonary veins unconnected with left atrium, whose confluence joining into vertical vein drained right-inferiorly to portal vein or hepatic vein through diaphragm. Three parallel vessels including vertical vein, abdominal aorta and inferior vena cava arranged anteriorly, left-posteriorly and right-posteriorly with the opposite flow directions of inferior vena cava and the other two were found on sub-costal view. Sites of the drainage to the infra-diaphragm veins located portal vein in 8 patients. Stenosis of site of vertical vein connecting to portal vein or hepatic veins occurred in 3 patients.

CONCLUSION

Echocardiography has significant value in the diagnosis of pediatric ITAPVC and is capable of providing important structural and hemodynamic information for preoperative assessment of surgery. With multiple windows and multiple sections, ITAPVC could be diagnosed accurately by echocardiography. However, it is necessary to differentiate ITAPVC with intrahepatic portosystemic venous shunts or hepatic arteriovenous fistula.

[Efficacy of intra-aortic balloon counterpulsation in patients with acute myocardial infarction according to the type of revascularization: a meta-analysis]

OBJECTIVE

To evaluate the effects of intra-aortic balloon counterpulsation (IABP) on mortality in patients with acute myocardial infarction according to the type of revascularization.

METHODS

Recruited randomized controlled trials of IABP compared with no-IABP controls in acute myocardial infarction patients from January 1970 to May 2015 were searched from Medline, Embase and Cochrane Library, according to inclusion criteria and exclusion criteria. These data were analyzed using the methods recommended by the Cochrane Collaboration's software RevMan 5.0. Revascularization included thrombolytic therapy, percutaneous coronary intervention (PCI), or coronary artery bypass grafting.

RESULTS

(1) Eleven randomized controlled trials were enrolled for analysis with 1 102 patients in IABP group, 1 123 in no-IABP control group. (2) Compared with no-IABP control group, IABP could not significantly decrease the in-hospital or 30 day mortality (OR=0.84, 95%CI 0.65-1.09, P=0.20). (3)Compared with no-IABP control group, IABP could not significantly decrease the in-hospital or 30 day mortality in thrombolytic patients(OR=0.64, 95%CI 0.25-1.61, P=0.34), in PCI patients (OR=0.89, 95%CI 0.68-1.18, P=0.42), and in coronary artery bypass grafting patients(OR=0.46, 95%CI 0.13-1.63, P=0.23). (4)The difference reached borderline signiicance between no-IABP control group and IABP group in patients using IABP before PCI(OR=0.47, 95%CI 0.22-1.00, P=0.05), but not in case of after PCI(OR=1.33, 95%CI 0.63-2.79, P=0.45).

CONCLUSIONS

IABP does not decrease the in-hospital or 30 day mortality of acute myocardial infarction patients who received thrombolytic therapy, PCI, or coronary artery bypass grafting. But IABP might decreases the in-hospital or 30 day mortality in patients when used before PCI.

Bioremediation of 1,2-dichloroethane contaminated groundwater: Microcosm and microbial diversity studies

In this study, the effectiveness of bioremediating 1,2-dichloroethane (DCA)-contaminated groundwater under different oxidation-reduction processes was evaluated. Microcosms were constructed using indigenous bacteria and activated sludge as the inocula and cane molasses and a slow polycolloid-releasing substrate (SPRS) as the primary substrates. Complete DCA removal was obtained within 30 days under aerobic and reductive dechlorinating conditions. In anaerobic microcosms with sludge and substrate addition, chloroethane, vinyl chloride, and ethene were produced. The microbial communities and DCA-degrading bacteria in microcosms were characterized by 16S rRNA-based denatured-gradient-gel electrophoresis profiling and nucleotide sequence analyses. Real-time polymerase chain reaction was applied to evaluate the variations in Dehalococcoides spp. and Desulfitobacterium spp. Increase in Desulfitobacterium spp. indicates that the growth of Desulfitobacterium might be induced by DCA. Results indicate that DCA could be used as the primary substrate under aerobic conditions. The increased ethene concentrations imply that dihaloelimination was the dominate mechanism for DCA biodegradation.

Sb-induced phase control of InAsSb nanowires grown by molecular beam epitaxy

For the first time, we report a complete control of crystal structure in InAs(1-x)Sb(x) NWs by tuning the antimony (Sb) composition. This claim is substantiated by high-resolution transmission electron microscopy combined with photoluminescence spectroscopy. The pure InAs nanowires generally show a mixture of wurtzite (WZ) and zinc-blende (ZB) phases, where addition of a small amount of Sb (∼2-4%) led to quasi-pure WZ InAsSb NWs, while further increase of Sb (∼10%) resulted in quasi-pure ZB InAsSb NWs. This phase transition is further evidenced by photoluminescence (PL) studies, where a dominant emission associated with the coexistence of WZ and ZB phases is present in the pure InAs NWs but absent in the PL spectrum of InAs0.96Sb0.04 NWs that instead shows a band-to-band emission. We also demonstrate that the Sb addition significantly reduces the stacking fault density in the NWs. This study provides new insights on the role of Sb addition for effective control of nanowire crystal structure.

Cancer therapy improvement with mesoporous silica nanoparticles combining photodynamic and photothermal therapy

In this work, we develop novel mesoporous silica composite nanoparticles (hm-SiO2(AlC4Pc)@Pd) for the co-delivery of photosensitizer (PS) tetra-substituted carboxyl aluminum phthalocyanine (AlC4Pc) and small Pd nanosheets as a potential dual carrier system to combine photodynamic therapy (PDT) with photothermal therapy (PTT). In the nanocomposite, PS AlC4Pc was covalently conjugated to a mesoporous silica network, and small Pd nanosheets were coated onto the surface of mesoporous silica by both coordination and electrostatic interaction. Since small Pd nanosheets and AlC4Pc display matched maximum absorptions in the 600-800 nm near-infrared (NIR) region, the fabricated hm-SiO2(AlC4Pc)@Pd nanocomposites can generate both singlet oxygen and heat upon 660 nm single continuous wavelength (CW) laser irradiation. In vitro results indicated that the cell-killing efficacy by simultaneous PDT/PTT treatment using hm-SiO2(AlC4Pc)@Pd was higher than PDT or PTT treatment alone after exposure to a 660 nm CW-NIR laser.

Two novel SNPs in the coding region of the bovine PRDM16 gene and its associations with growth traits

As a zinc-finger protein, PR domain containing 16 (PRDM16) controls brown fat determination by stimulating brown fat-selective genes expression while suppressing the expression of genes selective for white fat cells, whose mutations were associated with myelodysplastic syndrome (MDS) and leukemogenesis in human and murine model of leukemia. To date, no polymorphisms of PRDM16 gene in bovine had been reported. Herein, PCR-SSCP and DNA sequencing methods were employed to screen the genetic variation within PRDM16 gene in 1031 Chinese indigenous bovine. The results revealed two novel silent mutations: XM_001788152: m.1641T>C (547aa), 1881G>A (627aa). Hence, we described the PvuII and HaeIII forced PCR-RFLP methods for detecting these mutations, respectively. In the forced PCR-RFLP analysis with PvuII, the frequencies of bovine PRDM16-C allele varied from 0.044 to 0.506 in four Chinese native breeds. In the forced PCR-RFLP analysis with HaeIII, the frequencies of bovine PRDM16-G allele were 0.474, 0.494, 0.576 and 0.906 for Jiaxian (JX), Nanyang (NY), Qinchuan (QC) and Chinese Holstein (CH) population. Significant statistical differences between genotypic frequencies implied that both of the polymorphic loci were significantly associated with cattle breeds by the chi square test (chi2 = 190.058, P < 0.001 and chi2 = 118.239, P < 0.001 for PvuII; chi2 = 209.842, P < 0.001 and chi2 = 108.711, P < 0.001 for HaeIII). The associations of the PvuII and HaeIII forced PCR-RFLPs of bovine PRDM16 loci with growth traits were analyzed in Nanyang breed. The two SNPs were associated with body weight and average daily gain in Nanyang aged 12 months, individuals with genotype TT and AA showed significantly better body weight (P < 0.05) and average daily gain (P < 0.01) at 12 months, respectively.

Health risks of heavy metals in contaminated soils and food crops irrigated with wastewater in Beijing, China

Consumption of food crops contaminated with heavy metals is a major food chain route for human exposure. We studied the health risks of heavy metals in contaminated food crops irrigated with wastewater. Results indicate that there is a substantial buildup of heavy metals in wastewater-irrigated soils, collected from Beijing, China. Heavy metal concentrations in plants grown in wastewater-irrigated soils were significantly higher (P<or=0.001) than in plants grown in the reference soil, and exceeded the permissible limits set by the State Environmental Protection Administration (SEPA) in China and the World Health Organization (WHO). Furthermore, this study highlights that both adults and children consuming food crops grown in wastewater-irrigated soils ingest significant amount of the metals studied. However, health risk index values of less than 1 indicate a relative absence of health risks associated with the ingestion of contaminated vegetables.

Relevance of ventricular electrical dispersion to arrhythmogenesis in ischemic myocardium--a simulation study

A computer simulation method was used to study the possible role of electrical dispersion induced by regional ischemia in the mechanisms underlying cardiac arrhythmias. Ischemic cells were simulated by considering the three major component conditions of acute ischemia (elevated extracellular K+ concentration, acidosis and anoxia) at the level of ionic currents and ionic concentrations. An ischemic area was introduced into a homogeneous healthy tissue to create a localized inhomogeneity. The constructed models were solved using the operator splitting and adaptive time step methods. The numerical experiments showed that action potential durations (APDs) of ischemic cells did not change with beats of shorter or longer cycle length. The smaller percentage increase of slow component of the delayed rectifier K+ current, I(ks), and smaller outward Na+-Ca2+ exchange current were found to be the ionic mechanisms underlying the decreased rate dependence in ischemic cells. The results suggest that ischemia flattens the APD restitution curve; however, the dispersion of refractory period can be greatly increased by a premature beat in the constructed inhomogeneous sheet. This demonstrates that the dispersion of refractoriness rather than APD by a premature beat contributes to reentrant tachyarrhythmias in the locally ischemic tissue.

Cationic niosomes as gene carriers: preparation and cellular uptake in vitro

Cationic niosomes of sorbitan monoesters were prepared using film hydration method and tested for their effect on delivery of antisense oligonucleotides (OND) in a COS-7 cell line. These formulations showed positive results on cellular uptake of antisense oligonucleotides. Especially, cationic niosomes of Span 40 and 60 have a more significant effect.

Theta-burst repetitive transcranial magnetic stimulation suppresses specific excitatory circuits in the human motor cortex

In four conscious patients who had electrodes implanted in the cervical epidural space for the control of pain, we recorded corticospinal volleys evoked by single-pulse transcranial magnetic stimulation (TMS) over the motor cortex before and after a 20 s period of continuous theta-burst stimulation (cTBS). It has previously been reported that this form of repetitive TMS reduces the amplitude of motor-evoked potentials (MEPs), with the maximum effect occurring at 5-10 min after the end of stimulation. The present results show that cTBS preferentially decreases the amplitude of the corticospinal I1 wave, with approximately the same time course. This is consistent with a cortical origin of the effect on the MEP. However, other protocols that lead to MEP suppression, such as short-interval intracortical inhibition, are characterized by reduced excitability of late I waves (particularly I3), suggesting that cTBS suppresses MEPs through different mechanisms, such as long-term depression in excitatory synaptic connections.

Physiological studies in carriers of the DYT1 gene mutation

The DYT1 gene mutation is associated with early onset generalised dystonia. However, only 30-40 per cent of gene carriers develop symptoms. We have used electrophysiological tests to search for subclinical effects of the presence of the mutation in non-manifesting cases and compared these with those seen in clinically affected cases and healthy controls. Clinically affected patients had the same pattern of abnormalities in spinal and motor cortical circuits as described previously in non-genetically characterised patients. Non-manifesting cases had some but not all of these defects, suggesting that additional genetic or environmental factors may be needed to produce the full range of physiological deficiencies needed to give rise to clinical symptoms.

Preparation of transmission electron microscopy cross-section specimens of crack tips using focused ion beam milling

The preparation of transmission electron microscope (TEM) thin foil specimens from metal alloys containing cracks is usually thwarted by the difficulty in preventing preferential erosion of material along the flanks and at the tips of cracks. Recent developments in focused ion beam (FIB) micromachining methods have the potential to overcome this inherent problem. In this article we describe the development of new procedures, one using FIB alone and the other using a combination of FIB with more conventional ion milling to generate TEM specimens that largely retain the microstructural information at stress corrosion cracks in austentic alloys. Examples of corrosion product phase identification and interfacial segregation are included to verify that detailed information is not destroyed by ion bombardment during specimen preparation.

Measurements of the cross section for e(+)e(-) --> hadrons at center-of-mass energies from 2 to 5 GeV

We report values of R = sigma(e(+)e(-)-->hadrons)/sigma(e(+)e(-)-->mu(+)mu(-)) for 85 center-of-mass energies between 2 and 5 GeV measured with the upgraded Beijing Spectrometer at the Beijing Electron-Positron Collider.

Signal transduction in neuronal migration: roles of GTPase activating proteins and the small GTPase Cdc42 in the Slit-Robo pathway

The Slit protein guides neuronal and leukocyte migration through the transmembrane receptor Roundabout (Robo). We report here that the intracellular domain of Robo interacts with a novel family of Rho GTPase activating proteins (GAPs). Two of the Slit-Robo GAPs (srGAPs) are expressed in regions responsive to Slit. Slit increased srGAP1-Robo1 interaction and inactivated Cdc42. A dominant negative srGAP1 blocked Slit inactivation of Cdc42 and Slit repulsion of migratory cells from the anterior subventricular zone (SVZa) of the forebrain. A constitutively active Cdc42 blocked the repulsive effect of Slit. These results have demonstrated important roles for GAPs and Cdc42 in neuronal migration. We propose a signal transduction pathway from the extracellular guidance cue to intracellular actin polymerization.

[Effects of mixed cord blood serum on long-term culture of bone marrow hematopoietic cells]

AIM

To demonstrate the role of cord blood serum on dte long-term culture of bone marrow and provide the experimental foundation for its clinical use, the response of the bone marrow mononuclear cells to the mixed cord blood serum was investigated on the basis of Dexter culture system.

METHODS

In ten samples of human bone marrow, 1 x 10(6) bone marrow mononuclear cells were planted onto the stromal cells layer and cultured for five weeks, Cobblestone area forming cells (CAFC), long-term colony-initiation cells (LTC-IC), and the nuclear cells count in the supernatant was observed.

RESULTS

CAFC, LTC-IC were 37.1 +/- 12.4/(ml. well), 40.9 +/- 10.6/(ml. well) respectively in control group. The accounts were increased in the group of 10% MCBS, although it was less than that in mixed cytokines group. When combined with cytokines, 10% MCBS enhanced the growth of CAFC and LTC-IC obviously compared with that when cytokines were used alone. 20% MCBS failed to substitute the role of mixed cytokines plus fatal calf serum on the expansion of CAFC, LTC-IC and NCC.

CONCLUSION

MCBS have the activity of stimulation for hematopoietic stem cells, which is analogous to SCF, IL-3, etc. Its nature and concentration remain to be investigated extensively.

[Neuregulin/ErbB signal transduction pathway in the development of nervous system]

Neuregulins are a family of structurally-related polypeptides encoded by four distinct genes. Three isoforms of neuregulin (NRG1, 2, and 3) are highly expressed in the developing and adult brain, among which NRG1 is best characterized. NRG1 has multiple functions essential for the development of the nervous system. It promotes growth and differentiation of glial cells and regulates the migration of cerebellar granule cells along radial glial fibers. During synaptogenesis, NRG1 induces the expression of acetylcholine receptor at the neuromuscular junction and in CNS, and expression of the NMDA receptor NR2C subunit and GABAA receptors in cerebellar granule cells. Recent studies indicate that NRG receptors are densely distributed in the postsynaptic membrane, suggesting that NRGs may play an important role in synaptic plasticity. We review recent progress in studies of NRG, their functions, and signaling mechanisms.

Mechanism of cardioprotection by resveratrol, a phenolic antioxidant present in red wine (Review)

Coronary heart disease (CHD) has been and remains a major contributor to morbidity and mortality in developed countries. The most common form of CHD in the western world is atherosclerosis (AS), especially of the major coronary arteries. Failure to maintain an intact endothelium, as a result of episodic and/or persistent injury and perturbation of the vascular endothelium, promotes formation of fatty streaks which are considered initiation events of AS. Cellular constituents contributing to endothelial injury include endothelial cells, monocytes, platelets, and smooth muscle cells. Individuals diagnosed with AS face complex, enduring clinical complications and enormous medical costs. Simple and easily compliant prevention and treatment measures are therefore strategic considerations in the management of this vascular disease. Based on known risk factors for CHD, priorities in AS prevention should include smoking cessation, blood pressure control, and diet modification. In recent years, the possible benefits of low to moderate consumption of alcoholic beverages, particularly of red wine, in the prevention of heart disease has received increasing attention and debate in the popular media as well as in the scientific community. Such attention has been prompted by research findings supporting a relationship between red wine consumption and the French paradox. This phenomenon refers to people residing in certain parts of France where red wine is customarily consumed during meals having a low CHD mortality, despite living a lifestyle considered to have comparably high CHD risks, as those in the US and many other developed countries. Studies have reported that the cardioprotective effects of red wine are greater than those attributed solely to ethanol and other types of alcoholic beverages. The mechanism(s) underlying the greater CHD protective benefits of red wine have not been elucidated. Recently the polyphenol resveratrol (3,5,4'-trihydroxy-trans-stilbene), known to be abundantly present in red wine, compared to white wine, beer, or spirits, has been demonstrated to elicit a broad spectrum of biological responses in in vitro and in animal studies, including effects that are compatible with the cardioprotective roles proposed for red wine. These recently described effects of resveratrol will be reviewed in this article. We will first summarize published data showing an inverse association between consumption of alcoholic beverages/red wine and risk of CHD. A review of biosynthesis of resveratrol and its presence in food groups and wines will follow. Recent studies relating exposure to wine/resveratrol with reduction in myocardial damage during ischemia-reperfusion, modulation of vascular cell functions, inhibition of LDL oxidation, and suppression of platelet aggregation will be presented. The last section of this review will focus on a discussion of mechanism(s) by which resveratrol acts as a potential cardioprotective agent.

Erbin is a protein concentrated at postsynaptic membranes that interacts with PSD-95

Neuregulin is a factor essential for synapse-specific transcription of acetylcholine receptor genes at the neuromuscular junction. Its receptors, ErbB receptor tyrosine kinases, are localized at the postjunctional membrane presumably to ensure localized signaling. However, the molecular mechanisms underlying synaptic localization of ErbBs are unknown. Our recent studies indicate that ErbB4 interacts with postsynaptic density (PSD)-95 (SAP90), a PDZ domain-containing protein that does not interact with ErbB2 or ErbB3. Using as bait the ErbB2 C terminus, we identified Erbin, another PDZ domain-containing protein that interacts specifically with ErbB2. Erbin is concentrated in postsynaptic membranes at the neuromuscular junction and in the central nervous system, where ErbB2 is concentrated. Expression of Erbin increases the amount of ErbB2 labeled by biotin in transfected cells, suggesting that Erbin is able to increase ErbB2 surface expression. Furthermore, we provide evidence that Erbin interacts with PSD-95 in both transfected cells and synaptosomes. Thus ErbB proteins can interact with a network of PDZ domain-containing proteins. This interaction may play an important role in regulation of neuregulin signaling and/or subcellular localization of ErbB proteins.

Expression of PSD-95/SAP90 is critical for N-methyl-D-aspartate receptor-mediated thermal hyperalgesia in the spinal cord

PSD-95/SAP90, a molecular scaffold protein, attaches the N-methyl-D-aspartate receptor to cellular signaling pathways through PSD-95/DLG/Z0-1 domain interactions at neuronal synapses.(5,9) This suggests that PSD-95/SAP90 might be involved in many physiological and pathophysiological actions triggered via the N-methyl-D-aspartate receptor in the central nervous system. Here, we present evidence that suppression of the expression of PSD-95/SAP90 in the spinal cord significantly attenuated facilitation of the tail-flick reflex triggered through N-methyl-D-aspartate receptor activation but not baseline tail-flick reflex latency. Moreover, PSD-95/SAP90's messenger RNA and protein were enriched in the spinal cord and selectively distributed in the superficial dorsal horn, where PSD-95/SAP90 overlapped with the N-methyl-D-aspartate receptor. In spinal cord neurons, PSD-95/SAP90 interacted with the N-methyl-D-aspartate receptor subunits 2A/2B. It is indicated that activation of the N-methyl-D-aspartate receptor in spinal hyperalgesia results in association of the N-methyl-D-aspartate receptor with PSD-95/SAP90 and that PSD-95/SAP90 is required for noxious thermal hyperalgesia triggered via the N-methyl-D-aspartate receptor at the spinal cord level. The present findings may provide novel insights into the mechanisms for persistent sensitization of the somatosensory system.

[Isolation and verification of Triticum aestivum-Eremopyrum orientale addition lines and substitution lines by GISH]

Eremopyrum is a potential genus in wheat improvement. To breed T. aestivum-Er. orientale additional and substitutional lines, chromosome number of 96 BC2F3 individuals were accounted. Fifteen plants with 2n = 43 and eight plants with 2n = 44 were checked out. GISH results of the individuals with 43 chromosomes showed that they blonged to three different monosomic additions. Two disomic additions, one double-monosomic addition, one trible-monosomic addition and one monosomic addition were found in the 2n = 44 individuals. One double-monosomic substitution and one monosomic substitution were obtained. We also proved that it is relatively easier to obtain addition lines in the selfing population than to obtain double-monosomic additions.

Regulation of neuregulin signaling by PSD-95 interacting with ErbB4 at CNS synapses

Neuregulins (NRGs) and their receptors, the ErbB protein tyrosine kinases, are essential for neuronal development, but their functions in the adult CNS are unknown. We report that ErbB4 is enriched in the postsynaptic density (PSD) and associates with PSD-95. Heterologous expression of PSD-95 enhanced NRG activation of ErbB4 and MAP kinase. Conversely, inhibiting expression of PSD-95 in neurons attenuated NRG-mediated activation of MAP kinase. PSD-95 formed a ternary complex with two molecules of ErbB4, suggesting that PSD-95 facilitates ErbB4 dimerization. Finally, NRG suppressed induction of long-term potentiation in the hippocampal CA1 region without affecting basal synaptic transmission. Thus, NRG signaling may be synaptic and regulated by PSD-95. A role of NRG signaling in the adult CNS may be modulation of synaptic plasticity.

[Flavonoids from Shuteria pampaninianna Hand.-Mazz]

OBJECTIVE

To investigate the chemical constituents of the herbs of Shuteria pampaninianna.

METHOD

Using polyamide columine chromatography and NMR spectra to isolate pure flavonods and determine their structures.

RESULT

Two flavonoids have been isolated from whole plant of S. pampaninianna and identified as myricetin(1) and ampelopsin(2) respectively.

CONCLUSION

Both 1 and 2 were obtained from this plant for the first time.

Time-course analysis of stretch reflexes in hemiparetic subjects using an on-line spasticity measurement system

Spasticity after a stroke is usually assessed in a score form by subjectively determining the resistance of a joint to an externally imposed passive movement. This work presents a spasticity measurement system for on-line quantifying the stretch reflex of paretic limbs. Four different constant stretch velocities in a ramp-and-hold mode are used to elicit the stretch reflex of the elbow joint in spastic subjects. The subjects are tested at supine position with the upper limb stretched towards the ground, in contrast with the horizontally stretched movement used in other studies. By subtracting the baseline torque, reflex torque measured at a selected low stretch velocity of 5 deg/sec, the influence of gravity torque and inertial in vertical stretching mode can be minimized. The averaged speed-dependent reflex torque (ASRT), defined as the measured torque deviated from the baseline torque, is used for quantifying the spastic hypertonia. Four subjects having incurred cerebrovascular accident (CVA) are recruited for time-course study in which the measurements are taken at 72 hours, one week, one month, three months, and six months after onset of stroke. During the development of spasticity, the changes of ASRT and velocity sensitivity of ASRT of the involved and the intact elbow joints are discussed.

Preparation and identification of activity of anti-HPV-6b/11E1 universal ribozyme--Rz1198 in vitro

AIM

To study the preparation and cleavage activity of Rz1198 directed against HPV-6bE1 and HPV-11E1 (HPV-6b/ 11E1) transcripts in vitro.

METHODS

HPV-6b/11E1 gene fragments were cloned into T-vector under the control of T7 promoter. 32P-labeled HPV-6b/11E1 transcripts as target-RNAs were transcribed in vitro and purified by PAGE. Rz1198 gene designed as a universal ribozyme for both HPV-6b/11E1 transcripts was cloned into vector p1.5 between 5'-cis-Rz and 3'-cis-Rz. 32P-labeled Rz1198 transcript was gel-purified, incubated with target-RNAs at different conditions and autoradiographed after denaturing gel-electrophoresis.

RESULTS

Rz1198 was active at 37 degrees C. The optimal temperature was 50 degrees C. For HPV-6bE1, km = 12.2 nmol/L, kcat = 0.18 min(-1); For HPV-11E1, km = 14.7 nmol/L, kcat = 0.14 min(-1). All these revealed that the design of Rz1198 was correct. It could be a universal ribozyme for the two substrates--HPV-6bE1 and HPV-11E1 transcripts.

CONCLUSION

Rz1198 prepared in vitro possesses the perfect specific catalytic cleavage activity. It leads to the expectation that, in the future, it will be possible to develop a new nucleic acid drug from Rz1198 which can efficiently inhibit the replication of HPV-6b/11 DNA in vivo.

Resveratrol inhibits copper ion-induced and azo compound-initiated oxidative modification of human low density lipoprotein

To investigate whether resveratrol, a polyphenolic compound in red wine, affects the oxidation of human low density lipoprotein (LDL), LDL purified from normolipidemic subjects was subjected to Cu(2+)-induce and azo compound-initiated oxidative modification, with and without the addition of varying concentrations of resveratrol. Modification of LDL was assessed by the formation of thiobarbituric acid reactive substances (TBARS) and changes in the relative electrophoretic mobility (REM) of LDL on agarose gels. Resveratrol (50 microM) reduced TBARS and REM of LDL during Cu(2+)-induced oxidation by 70.5% and 42.3%, respectively (p < 0.01), and prolonged the lag phase associated with the oxidative modification of LDL by copper ion or azo compound. These in vitro results suggest that resveratrol may afford protection of LDL against oxidative damage resulting from exposure to various environmental challenges, possibly by acting as a free radical scavenger.

Grafting of genetically modified human fetal fibroblasts to produce human butyrylcholinesterase in mice

Human diploid fibroblast cultures were established from fetal skin tissue. Enzymic dissociation yielded cultures of higher growth capacity of fibroblasts than those prepared by mechanical dissociation followed by spontaneous outgrowth of cells. Transfer of recombinant human butyrylcholinesterase (BChE, EC 3.1.1.8) gene into primary human fibroblasts was achieved successfully using lipofection and retrovirus-mediated transfection. The analysis of drug-resistant colonies suggested the presence of the transcripted BChE mRNA in the cytoplasm of transfected cells. The secreted BChE protein in culture medium was assayed for enzyme activity using butyrylthiocholine as substrate. The genetically modified fibroblasts were mixed with rat tail collagen and transplanted subcutaneously and intraperitoneally to mice. Immunoreactive human BChE appeared in the plasma from the transplanted mice. reaching the top level at day 13. It was not present any longer in most of the mice 20 days later.

Episodic nocturnal wandering and complex visual hallucination. A case with long-term follow-up

Episodic nocturnal wandering is rare and thought to be an atypical form of nocturnal epilepsy which is responsive to anticonvulsant therapy. We report a case of adult-onset episodic sleep-walking and daytime complex visual hallucination. Ambulatory EEG recordings suggested that both events were ictal phenomenon. Interictal sphenoidal EEG and SPECT studies revealed an epileptogenic focus in the left anterior temporal lobe. During the nocturnal wanderings, the patient had bizarre but non-violent behaviour, and was at risk of minor or severe injury to himself. Both events were completely controlled by carbamazepine for a follow-up period of 8 years. The present case further supports the notion that episodic nocturnal wandering represents an unusual type of nocturnal complex partial seizures.

[Ischemic preconditional protection of ischemia reperfusion injury on isolated hearts of ground squirrel and rat]

The protective effects of ischemic preconditioning on ischemia-reperfusion injury was investigated using isolated Langendorff perfusing hearts from ground squirrel and rat. In Preconditioning I group hearts were first perfused with Krebs-Henseleit solution for 10 min to establish a steady state, then stopped for 15 min to establish global ischemia, and finally followed by 10 min ischemia and 10 min reperfusion. In Preconditioning II group there were three cycles of 5 min ischemia + 5 min reperfusion after 10 min equilibration and then the final 10 min ischemia and 10 min reperfusion were followed. It was found that in group I during the final 10 min ischemia period there was remarkable augmentation of CK release from both animal's hearts. But in group II CK release decreased markedly during the same ischemic period. CK release during final 10 min reperfusion period also decreased significantly in group II in comparison with group I. The incidence of arrhythmias occurred in both animal's hearts was markedly reduced in group II rather than group I. In conclusion, short episode ischemic preconditioning protect subsequent ischemia-reperfusion injury on isolated hearts from ground squirrel and rat.