[Retrospective analysis of diagnosis and treatment of tuberculosis in designated medical institutions in China from 2017 to 2022]

Objective: To understand the status of tuberculosis diagnosis and treatment capacity and the development and changes of tuberculosis diagnosis and treatment in provincial and municipal designated medical institutions in China from 2017 to 2022, so as to provide a basis for the formulation of relevant policies for the improvement and development of designated medical institutions for tuberculosis and the tuberculosis prevention and treatment service system, and to provide reasonable support for further strengthening the capacity of designated medical institutions for tuberculosis. Methods: This study was initiated and carried out by Beijing Chest Hospital affiliated to Capital Medical University/Clinical Center for Tuberculosis Prevention and Control of China CDC (hereinafter referred to as "Clinical Center") by means of questionnaire survey, and the investigation was carried out from March to November 2023. During this period, the clinical center distributed questionnaires to the hospital member units of "Beijing Tuberculosis Diagnosis and Treatment Technology Innovation Alliance", retrospectively collected their tuberculosis-related diagnosis and treatment data from 2017 to 2022, and used descriptive statistical methods to analyze the number of tuberculosis beds, outpatients and hospitalizations in medical institutions. The results were expressed in absolute numbers (percentages), and three-line tables, bar charts and line charts were drawn to describe the analysis results and changing trends. Results: The 54 medical institutions surveyed in this survey included 21 provincial-level designated medical institutions and 33 prefecture-level designated medical institutions. Most medical institutions have set up clinical departments, auxiliary departments and functional departments to undertake public health tasks of infectious diseases. The tuberculosis laboratory in the hospital has a comprehensive ability and has the detection technology needed for most tuberculosis diagnosis; The number of tuberculosis beds, children's tuberculosis beds and ICU beds all showed an increasing trend from 2017 to 2022. The proportion of tuberculosis beds in the hospital decreased slightly, from 39.31% in 2017 to 34.76% in 2022, showing a slight downward trend. Compared with the hospital surveyed, the number of tuberculosis outpatients in 2019 was 562 029, and the number of outpatients in 2020-2022 was 462 328, 519 630 and 424 069 respectively, which was significantly lower than that in 2019. The number of tuberculosis outpatients in medical institutions decreased significantly from 2020 to 2022. By analyzing the proportion of patients with different types of tuberculosis, the proportion of sensitive tuberculosis outpatients in 2017-2022 decreased from 84.49% in 2017 to 78.05% in 2022, showing a downward trend year by year. The proportion of patients with multidrug-resistant/ rifampin-resistant tuberculosis increased from 2.03% in 2017 to 7.18% in 2022. From 2017 to 2019, the total number of inpatients with tuberculosis showed an upward trend. Compared with 2019, the number of inpatients in 2020, 2021 and 2022 showed a downward trend, and the decline in 2020 was large (down 14.94% compared with 2019). Among the inpatients, the absolute number and proportion of patients with sensitive pulmonary tuberculosis remained relatively stable, and the number and proportion of inpatients with multidrug-resistant/rifampin-resistant pulmonary tuberculosis increased year by year. Conclusions: Most medical institutions have the capacity to carry out routine diagnosis and treatment of tuberculosis, but the public health function needs to be strengthened. The transformation of medical institutions requires proper guidance and adequate support. During 2019-2022, most medical institutions were affected by the COVID-19 epidemic, and their tuberculosis diagnosis and treatment work also changed to varying degrees. During this period, hospitals took various measures to overcome difficulties and tried their best to maintain the normal development of tuberculosis diagnosis and treatment, and the tuberculosis diagnosis and treatment work of various institutions gradually resumed in 2022.

[Feasibility study of expectant management of different degrees of vaginal fluid in pregnant women with premature rupture of membranes in the second trimester]

Objective: To investigate the feasibility of expectant management of different degrees of vaginal fluid in pregnant women with premature rupture of membranes in the second trimester. Methods: A retrospective cohort study was conducted to collect 103 pregnant women who were diagnosed with premature rupture of membranes in the second trimester of pregnancy and insisted on continuing the pregnancy in Shanxi Bethune Hospital from July 2012 to July 2022. According to the degree of vaginal fluid, pregnant women were divided into rupture group (with typical vaginal fluid, 48 cases) and leakage group (without typical vaginal fluid, 55 cases). The rupture latency (the time from rupture of membranes to termination of pregnancy), gestational weeks of termination, indications and methods of termination of pregnancy, maternal infection related indicators and perinatal outcomes were compared between the two groups. Univariate regression model was used to analyze the correlation between different degrees of vaginal fluid in pregnant women with premature rupture of membranes and maternal and neonatal outcomes. Results: (1) Obstetric indicators: there was no significant difference in the gestational age of rupture of membranes between the two groups (P>0.05). However, the proportion of rupture latency >28 days in the leakage group was significantly higher than that in the rupture group [42% (23/55) vs 13% (6/48); χ2=33.673, P<0.001], and the incidence of pregnancy termination ≥28 weeks was significantly higher [47% (26/55) vs 19% (9/48); χ2=9.295, P=0.002]. (2) Indications and methods of termination: the incidence of progressive reduction of amniotic fluid as the indication for termination in the leakage group was significantly lower than that in the rupture group [22% (12/55) vs 42% (20/48); χ2=4.715, P=0.030], and the incidence of full-term termination in the leakage group was significantly higher than that in the rupture group [31% (17/55) vs 12% (6/48); χ2=5.008, P=0.025], while there were no significant differences in the indications of termination of pregnancy, including amniotic cavity infection, uterine contraction failure and fetal distress between the two groups (all P>0.05). The incidence of induced labor or spontaneous contraction in the leakage group was significantly lower than that in the rupture group [53% (29/55) vs 81% (39/48); χ2=9.295, P=0.002], while the cesarean section rate and vaginal delivery rate were similar between the two groups (both P>0.05). (3) Infection related indicators: the incidence of amniotic cavity infection in the leakage group was significantly higher than that in the rupture group [31% (17/55) vs 13% (6/48); χ2=4.003, P=0.045]. However, there were no significant differences in the elevation of inflammatory indicators, the positive rate of cervical secretion bacterial culture and the incidence of tissue chorioamnionitis between the two groups (all P>0.05). (4) Perinatal outcomes: the live birth rate in the leakage group was significantly higher than that in the rupture group [51% (28/55) vs 27% (13/48); χ2=5.119, P=0.024]. The proportion of live births with 1-minute Apgar score >7 in the leakage group was significantly higher than that in the rupture group [38% (21/55) vs 17% (8/48); χ2=4.850, P=0.028]. However, there were no significant differences in the birth weight of live births and the incidence of neonatal complications between the two groups (all P>0.05). (5) Univariate regression analysis showed that compared with the rupture group, the leakage group had a higher risk of pregnancy termination at ≥28 gestational weeks (RR=2.521, 95%CI: 1.314-4.838; P=0.002), amniotic infection (RR=2.473, 95%CI: 1.061-5.764; P=0.025), perinatal survival (RR=1.880, 95%CI: 1.104-3.199; P=0.014). Conclusion: Compared with pregnant women with typical vaginal fluid in the second trimester of premature rupture of membranes, expectant treatment for pregnant women with atypical vaginal fluid is more feasible, which could effectively prolong the gestational weeks and improve the perinatal live birth rate.

Ginseng promotes the function of intestinal stem cells through the Wnt/β-catenin signaling pathway in D-galactose-induced aging mice

BACKGROUND

Intestinal stem cells (ISCs) are the reservoir source of various types of intestinal cells, and the decline of stem cell function in the gut may be a potential factor for aging-related disease. The present study aimed to explore the regulatory mechanisms of Panax ginseng C.A.Meyer (Araliaceae, Panax genus) that could restore gut aging by enhancing intestinal function and regulating ISCs in aging mice based on the Wnt/β-catenin signaling pathway.

METHODS

A total of 60 ICR male mice were randomly divided into control, model, metformin, and ginseng water decoction (GWD) 3.6, 1.8, and 0.9 g/kg groups. The aging model was induced by 1 % D-galactose (s.c. 0.1 mL/10 g) for 28 days. Moreover, GWD was given to aging mice intragastrically (i.g.) once a day for 28 successive days. The learning memory ability, pathological status, and function in the ileum tissue, the activity of digestive enzymes, and short-chain fatty acid (SCFA) content in the colon were evaluated, and the related mechanism was investigated.

RESULTS

Ginseng can decrease the escape latency time and increase the swimming speed and the number of crossing platforms in aging mice. Moreover, the pathology of ileum tissue improved, the length of the intestinal villi increased, and the width of the villi and the depth of the crypts decreased. The activities of trypsin, α-amylase, and lipase increased in duodenal content and intestinal mucosa. In the colon, the content of SCFA, such as acetic acid, propionic acid and butyric acid, increased, indicating that ginseng significantly improves intestinal function impairment. The mRNA expressions and protein levels of β-catenin, C-myc, GSK-3β, Lgr5, and Olfm4 were upregulated in the ginseng group.

CONCLUSIONS

Ginseng improves intestinal function and regulates the function of ISCs in order to protect intestinal health by activating the Wnt/β-catenin signaling pathway in aging mice.

[Research and development of an air sampling tube for chlorobenzene compounds and its supporting determination method]

Objective: To establish a GDH-3 air sample tube for simultaneous determination of twelve kinds of chlorobenzene compounds (CBs) in workplace air by gas chromatography. And to established a matching determination method. Methods: In October 2020, the vapor and aerosol CBs in workplace air were collected by GDH-3 air sampling tube, and desorption and elution with 3.00 ml toluene for 15 min, then the solution separated by DB-23 capillary column, and finally detected with microcell electron capture detector. Results: The quantitative determination ranges of twelve isomers of CBs were 0.71×10(-3)-2000.00 mg/L, with the correlative coefficients were 0.99967-0.99998. The minimum detectable concentrations were 0.04-112.63 μg/m(3), and the minimum quantification concentrations were 0.14-375.42 μg/m(3) (15.00 L sample, 3.00 ml sample solution) . The average elution efficiencies were 96.00%-104.00%. The within-run relative standard deviations (RSDs) were 2.54%-6.12%, and the between-run RSDs were 3.85%-7.87%. Sealed samples could be stable at room temperature for at least 15 days. Conclusion: GDH-3 air sample tube can be used for simultaneous determination of twelve kinds of CBs in workplace air by gas chromatography. The established supporting measurement method meets the measurement requirements of the occupational health standard detection method, and the it's suitable for the simultaneous determination of 12 kinds of CBS in the air.

[Percutaneous biliary stent combined with brachytherapy for malignant obstructive jaundice: a multicenter retrospective controlled study]

Objective: To investigate the efficacy, safety and prognostic factors of percutaneous biliary stent combined with iodine-125 seed chain brachytherapy (radiotherapy) in the treatment of malignant obstructive jaundice. Methods: Data of 107 cases with malignant obstructive jaundice treated with percutaneous biliary stent implantation from January 2017 to December 2020 were retrospectively analyzed. Among them, 58 cases received biliary stent combined with iodne-125 seed chain brachytherapy (study group), and 49 cases received biliary stent implantation (control group). The changes of bilirubin, stent patency time, complications, overall survival (OS) and prognostic factors were analyzed in both groups. Results: The incidence of complications in the study group and the control group were 17.2% and 18.3% respectively, and the difference was not statistically significant (P=0.974). Serum total bilirubin levels were decreased significantly in both groups at one month after surgery (P<0.001). Postoperative stent patency time was significantly better in the study group (10.0±1.6 months) (95% CI: 8.2～12.5) than that in the control group (5.2±0.4 months) (95% CI: 4.1～6.0, P<0.001). The median OS was longer in the study group (11.2±1.8 months) (95% CI: 9.2～12.8) than that in the control group (8.0±1.1 months) (95% CI: 8.0～12.8, P<0.001). Multivariate analysis result showed that stent combined with brachytherapy (HR=0.08, 95% CI:0.04～0.15, P<0.001) and receiving further anti-tumor therapy after surgery (HR=0.27, 95% CI:0.15~0.49, P<0.001) were independent risk factors affecting the patency of biliary stents. Preoperative percutaneous transhepatic biliary drainage (HR=0.46, 95%CI:0.28～0.74, P=0.002), stent combined with brachytherapy (HR=0.23, 95%CI:0.14～0.39, P<0.001) and receiving further anti-tumor therapy after surgery (HR=0.37, 95%CI:0.22～0.61, P<0.001) were independent risk factors affecting OS. Conclusion: Percutaneous biliary stent combined with brachytherapy is safe and effective in the treatment of malignant obstructive jaundice, which can significantly prolong the patency time of biliary stent and the survival time of patients.

Dendritic cell TLR4 induces Th1-type immune response against Cryptosporidium parvum infection

The objective of this study was to investigate the mechanism of Toll-like receptor (TLR4)- mediated dendritic cell (DC) immune against Cryptosporidium parvum infection. C. parvum sporozoites were labeled with 5,6-carboxyfluorescein diacetate succinimidyl ester. Murine bone marrow-derived DCs were isolated, and divided into TLR4 antibody blocking (TAB; infected with 2 × 10⁵ labeled sporozoites and 0.5 μg TLR4 blocking antibody), TLR4 antibody unblocking (TAU; infected with 2 × 10⁵ labeled sporozoites), and blank control (BC; with 1.5 mL Roswell Park Memorial Institute 1640 medium) groups. The adhesion of Cryptosporidium sporozoites to DCs and CD11c⁺ levels were examined by fluorescence microscopy and flow cytometry. Male KM mice were orally injected with C. parvum. The proliferation of T lymphocytes in spleen, expression of cytokines in peripheral blood, and TLR4 distribution features in different organs were further determined by immunohistochemistry. A significantly higher expression of CD11c⁺ and higher C. parvum sporozoite adhesion were found in the TAU group compared with other groups. The expression of CD4⁺CD8^- /CD8⁺CD4^- in the spleen were obviously differences between the TAB and TAU groups. The expression of TLR4, interleukin IL-4, IL-12, IL-18 and IFN-γ improved in the TAU group compared with TAB group. Higher expression of TLR4 was detected in the lymph nodes of mice in the TAU group, with pathological changes in the small intestine. Hence, TLR4 could mediate DCs to recognize C. parvum, inducing Th1 immune reaction to control C. parvum infection.

[Active screening of intestinal carbapenem-resistant Enterobacteriaceae in high-risk patients admitted to the hematology wards and its effect evaluation]

目的

观察血液科肠道碳青霉烯类耐药的肠杆菌科细菌（CRE）主动筛查患者CRE定植、感染的特征，并评价主动筛查结合加强干预在血液科患者CRE感染预防控制中的效果。

方法

以2017年3月至2019年12月血液内科接受化疗或免疫抑制治疗且预期会出现粒细胞缺乏（粒缺）的患者为研究对象，进行至少3个时间点（治疗前、治疗后粒缺期、粒缺伴发热期）的肠道CRE筛查，以2016年12月至2017年2月血液内科未开展肠道CRE主动筛查的、接受化疗或免疫抑制治疗的115例患者为历史对照组，两组患者均进行CRE感染实时监测，CRE筛查阳性者均采取接触隔离措施，CRE筛查阳性者出现发热或者感染症状时启动针对CRE联合抗生素治疗。

结果

主动筛查患者CRE定植率为16.46%（66/401）；病种分布上，以急性白血病定植率最高，为23.03%（26/113）。66例筛查阳性患者中，其中第1次筛查阳性患者为27例，占40.9%（27/66），第2次筛查阳性患者为15例，占22.7%（15/66），第3次及以后筛查阳性患者为24例，占36.4%（24/66）。CRE定植病原菌中耐碳青霉烯类肺炎克雷伯菌（CRKP）最多，占54.55%（36/66）。主动筛查患者CRE感染率（2.49%）及死亡率（50.00%）低于历史对照组的11.30%及69.23%；干预期间10例CRE血流感染患者病原菌种类与前期主动筛查病原菌完全相同，符合率为100.0%。

结论

血液科病房急性白血病患者CRE定植率最高，CRKP是CRE定植、感染的主要病原菌，提高筛查频率可以显著提高筛查阳性率，采取主动筛查并及早干预能有效降低血液科患者CRE发生率及死亡率，CRE筛查阳性病原菌与后续CRE感染病原菌符合率高。恶性血液病患者肠道CRE筛查可以对后期CRE血流感染起到预警以及优化抗菌药物使用的作用。

Tailoring phase transformation strengthening and plasticity of nanostructured high entropy alloys

Metastable high entropy alloys (HEAs) have attracted extensive attention due to their excellent combination of high strength and great plasticity. In this work, we utilize constraining effects to tailor phase transformation strengthening and plasticity of nanostructured HEA ([double bond, length as m-dash]FeCoCrNi) thin films prepared by the magnetron sputtering technique via HEA/Cu and HEA/Ni nanotwinned nanolaminates (NTNLs). It is uncovered that the HEA/Cu NTNLs without phase transformation exhibit the fashion of "smaller is stronger" and HEA layers become more favorable to detwin at a smaller layer thickness (h). By contrast, the HEA/Ni NTNLs manifest an ultra-high peak hardness plateau accompanied by the FCC-to-HCP phase transformation in HEA layers at large h≥ 25 nm, whereas they manifest size-dependent hardness when detwinning occurs at smaller h. This unusual plastic deformation behavior of HEA/X (X = Cu, Ni) NTNLs was rationalized by partial-based mechanisms. These findings open a new avenue to achieve superior mechanical properties of HEAs particularly at the nanoscale.

Expression of Raptor and Rictor and their relationships with angiogenesis in colorectal cancer

Mammalian target of rapamycin (mTOR) has two subtypes, i.e., mTORC1 and mTORC2, which contain the Raptor and Rictor core molecules, respectively. The effect of Raptor and Rictor on hypoxia inducible factor (HIF)-1α, HIF-2α, and vascular endothelial growth factor (VEGF) in colorectal cancer (CRC) is unclear. In this work, we investigated the correlations among Raptor, Rictor, HIF-1α, HIF-2α, and VEGF expression in CRC. We subsequently analyzed the clinicopathological features of patients. Immunohistochemistry, western blot, and RT-PCR analyses were performed to detect the expression of Raptor, Rictor, HIF-1α, HIF-2α, and VEGF in 120 cases of CRC and 60 cases of normal colorectal mucosa. CD34 was used to label microvascular density (MVD), which was found to be higher in patients with positive Raptor or Rictor than in those with negative Raptor or Rictor. The positive rates of Raptor, Rictor, HIF-1α, HIF-2α, and VEGF in CRC were significantly higher than in normal colorectal mucosa. Raptor expression was positively correlated with HIF-1α and VEGF but not with HIF-2α expression. By contrast, Rictor expression was positively correlated with HIF-2α and VEGF but not with HIF-1α expression. Survival analysis further indicated that Raptor, Rictor, HIF-1α, HIF-2α, VEGF and lymph node metastasis were independent prognostic factors in CRC. To conclude, Raptor and Rictor expression was related to the initiation and development of CRC and angiogenesis in different ways. The combined detection of Raptor and Rictor is important for patients with colorectal carcinoma in prognosis and optimal therapy.

[Construction of mouse CCR3 gene RNAi lentivirus vector and its expression on mast cells]

Objective:The aim of this study is to screen the targeting chemokine receptor 3-RNA interference (CCR3-RNAi) lentiviral expression vector, infect mouse mast cells,observe the expression of this gene in mast cells and the interference efficiency of the virus vector.The pathogenesis of allergic rhinitis lays the foundation.Method:Three pairs of CCR3-shRNA sequences were constructed,and three pairs of double-stranded shRNA oligo were inserted into shRNA lentiviral vectors to construct three shRNA lentiviral recombinant plasmids.The recombinant vector and virus-packed auxiliary plasmids were co-transfected into 293T cells to obtain lentiviral plasmids.The lentiviral plasmids were then transfected into mouse bone marrow-derived mast cells in vitro and purified. The expression level of CCR3 mRNA in mast cells was verified by qRT-PCR,and the expression level of CCR3 protein in mast cells was detected by Western Blot.Result: It was confirmed by sequencing that the lentiviral vector of CCR3 shRNA was successfully constructed, transfected into 293T cells and packaged with virus. Finally the high purity PDSO19-PL-CCR3 lentiviral plasmid was obtained with a virus titer of 3.7×10⁸TU/ml.The lentiviral plasmid was used to infect mouse mast cells.RT-PCR and Western Blot detection assay showed that CCR3shRNA reduced the expression of CCR3 gene in mouse mast cells at the level of mRNA and protein.Conclusion: The CCR3 gene RNAi lentivirus expression vector was successfully constructed.It was found that it downregulated the expression level of CCR3 gene mRNA and protein in mouse mast cells,which laid the foundation for further research on its role in the pathogenesis of allergic rhinitis.

[Regulatory effect of exosomes secreted by vaginal wall fibroblasts on angiogenesis in patients with stress urinary incontinence]

Objective: Exosomes are considered to mediate intercellular communication by delivering biomolecules like mRNA, miRNA into recipient cells. The purpose of this study was to evaluate the effects of exosomes secreted by fibroblasts from women with stress urinary incontinence (SUI-EXO) on endothelial cells angiogenesis. Methods: Primary fibroblasts were acquired from periurethral vaginal wall tissues and exosomes were prepared by ultracentrifugation of fibroblasts cells conditioned medium. The expression levels of pro-angiogenic and anti-angiogenic genes were assessed using qRT-PCR analysis. Migration of endothelial cells was measured by transwell assay, and the effects of SUI-EXO on angiogenesis were evaluated by performing a tube formation assay in vitro. Results: SUI-EXO was successfully isolated from fibroblasts cells conditional medium and transferred to endothelial cells efficiently. When the endothelial cells were treated with SUI-EXO, the expression levels of pro-angiogenic genes in fibroblasts were downregulated, and the expression levels of anti-angiogenic genes were upregulated significantly (P<0.01). Endothelial cells exhibited a decreased migratory capacity after treatment with SUI-EXO compared to exosomes from health women (64.6±8.7 vs 114.5±14.2,P<0.01), and tube formation of endothelial cells was also significantly inhibited in the SUI-EXO treated group as determined by the increase of the tube length (87.6±13.3 vs 168.5±28.3,P<0.01). Conclusion: This study suggests that SUI-EXO plays related roles in regulating endothelial cells angiogenesis and SUI-EXO maybe involve in the pathogenesis of SUI.

[A study on the burden and causes of hospitalization and deaths in Shenzhen, between 1995 and 2014]

Objective: Data from the surveillance program was collected, to analyze the situation of hospitalization and cases of death with recorded causes, in Shenzhen, from 1995 to 2014. Situation of hospitalization and causes of deaths were studied in Shenzhen which had been a fast-developing city with growing number of immigrants so as to provide reference for decision-making on related prevention and control strategies. Methods: Data on hospitalizations and deaths collected from the surveillance program, were classified by both International Classification of Diseases (ICD)- 9 and ICD-10. A database was constructed with methods on related descriptive and trend analysis. Results: Around 6.3 million inpatients were seen in the past two decades in Shenzhen. The top five diseases for hospitalization were pregnancy childbirth and puerperium complications, respiratory diseases, injury and poisoning, digestive system diseases and circulatory system diseases, that accounting for 68.4% of all the hospitalization burden. The number of inpatients increased annually, with an 11 times increase during the past two decades. Proportions for pregnancy childbirth and puerperium complications, circulatory system diseases and urinary system diseases all showed increasing (χ(2)=53 806.94, 6 893.95 and 15 383.14, P<0.01), while proportions for injuries and poisoning, respiratory diseases, digestive system diseases showed a declining trend (χ(2)=131 480.09,1 711.84 and 11 367.66, P<0.01). Number of cumulative inpatient deaths exceeded 60 000, with the top five causes as malignant tumor, circulatory system diseases, injury and poisoning, respiratory system diseases and digestive system diseases, that accounting for 82.28% of all the inpatient deaths. Deaths due to circulatory system diseases, injury and poisoning increased and then decreased. Malignant tumor and respiratory diseases-induced deaths showed an increasing trend (χ(2)=1 546.48, 309.55, P<0.01), while induced deaths from disease of the other systems showed slight changes. The overall case fatality rate showed an annual decline (χ(2)=4 378.63, P<0.01), from 2.23% in 1995 to 0.74% in 2014, with mortality attribute to tumor, circulatory system disease decreased significantly. Conclusions: Shenzhen had been under an ageing transition, with relatively young population living in the city. Chronic diseases such as tumor gradually had become the major causes for heavy hospitalization burden on the population of Shenzhen.

[Research on the effect of RNA interference on mast cells in respiratory allergic diseases]

Respiratory allergic disease has become a major health problem in the 21st century.Mast cells are key effector cells of the respiratory anaphylaxis, and can form a variety of features of allergic inflammation by producting large numbers of inflammatory mediators.RNAi can affect the disease process by silencing gene expression, and has made significant process in the study of many diseases, but the research of targeting mast cells for the treatment of respiratory allergic diseases is rare.This review focuses on recent advances of the application of RNA interference on mast cell in respiratory allergic diseases, aming to further understand its application in the respiratory allergic diseases and research status, and broaden new ideas of treating respiratory allergies.

[Application of MDCT and post-processing in children with tracheal foreign body]

Objective:To explore the clinical value of MDCT and post-processing in children with suspected foreign body in trachea.Method:Two hundred patients with suspected tracheal foreign body were treated with 64-slice spiral CT (MDCT) and simulated endoscopic imaging,then compared with seen in bronchoscopy; Compare the results of MDCT and post-processing with the coincidence of intraoperative findings.Result:One hundred and eighty-four cases of positive children were examined by MDCT postprocessing technique and bronchoscopy,179 cases were obstructed by exogenous foreign body,5 cases were phlegm thrombosis (endogenous foreign body) obstruction; 16 cases of children with no foreign body diagnosed by MDCT post-processing technique were also examined by bronchoscopy. The results showed that there was a foreign body in 1 case,and the foreign body was located in the pharyngeal cleft (watermelon spermoderm),and the remaining 15 cases had no foreign body. MDCT and post-treatment techniques for children with tracheal foreign body diagnosis of 99.4% sensitivity,specificity of 75%.There was no significant difference in the detection rate of foreign body between the two techniques of MDCT and post-processing technique and bronchoscopy (P>0.05). Examed by MDCT and postprocessing,we can understand the specific location and size of foreign body,nature,shape preoperatively.Conclusion:Although MDCT and post-processing techniques can not be used to treat tracheal foreign bodies,but the diagnostic rate of bronchial foreign bodies is comparable to that of bronchoscopy. We could apply MDCT examination and post processing before the bronchoscopy,for foreign body inhalation history is not clear,or suspected airway foreign body. We can improve the level of diagnosis and treatment through guiding the operation of bronchoscopy focus.

[Pharyngeal space carcinoma ex pleomorphic adenoma：a case report]

Carcinoma ex pleomorphic adenoma is an epithelial malignant tumor of pleomorphic adenoma. This may be due to the accumulation of genetic instability caused by long-term pleomorphic adenomas. There are few reports of parapharyngeal space carcinoma ex pleomorphic adenoma in the literature study both at home and abroad. This article retrospectively summarized the clinical data of 1 case of pharyngeal space carcinoma ex pleomorphic adenoma and reviewed the literature. We strengthened the understanding of parapharyngeal space carcinoma ex pleomorphic adenoma, improve the accuracy of diagnosis and reduce misdiagnosis and mistreatment.

[Effect of CCR3 gene knockout on eosinophils in mice]

Objective:To investigate the effect of CCR3 gene knockout on the proliferation, maturation and apoptosis of eosinophils (EOS) in mice. Method:Bone marrow cells from CCR3 gene knockout mice (experimental group) and wild-type mice (control group) were cultured in vitro and induced differentiation into mature EOS. EOS proliferation was observed by cell counting.Expression of degranulation protein mRNA was detected by qRT-PCR. EOS apoptosis was detected by Annexin V-FITC/PI double staining method. Result:①The number of cells on the 0-14 day of EOS cultured in vitro showed that the number of cells in the experimental group was less than that in the control group at tenth, twelfth, fourteenth days, and the proliferation was slower, the difference was statistically significant (P<0.01). ②The test results of EOS cells apoptosis showed that, under the condition of containing 10 ng/ml IL-5 or no IL-5, the apoptosis rate of EOS cells in experimental group was higher than that in normal control group, the difference between both groups was statistically significant (P<0.01). ③The expression results of ECP, EPO, MBP mRNA in EOS showed that the expression levels of ECP, EPO, MBP mRNA in the experimental group compared with the normal control group were reduced in varying degrees, the difference between both groups was statistically significant (P<0.05). Conclusion:Knockout CCR3 gene can inhibit the proliferation and maturation of EOS and promote its apoptosis, which provides a theoretical basis for CCR3 as a target gene to treat allergic rhinitis.

[Efficacy and safety of pegylated interferon α-2b injection (Y shape, 40 kD) in treatment of patients with genotype 1/6 chronic hepatitis C]

Objective: To investigate the efficacy and safety of the new investigational drug pegylated interferon α-2b (Peg-IFN-α-2b) (Y shape, 40 kD) injection (180 µg/week) combined with ribavirin in the treatment of patients with genotype 1/6 chronic hepatitis C (CHC), with standard-dose Peg-IFN-α-2a combined with ribavirin as a positive control. Methods: A multicenter, randomized, open-label, and positive-controlled phase III clinical trial was performed. Eligible patients with genotype 1/6 CHC were screened out and randomly divided into Peg-IFN-α-2b(Y shape, 40kD) group and Peg-IFN-α-2a group at a ratio of 2:1. The patients in both groups were given oral ribavirin for 48 weeks in addition and then followed up for 24 weeks after drug withdrawal. Abbott Real Time HCV Genotype II was used to determine HCV genotype, and Cobas TaqMan quantitative real-time PCR was used to measure HCV RNA level at 0, 4, 12, 24, 48, and 72 weeks. Adverse events were recorded in detail. The primary efficacy endpoint was sustained virological response (SVR), and a non-inferiority test was also performed. Results: A total of 561 patients with genotype 1/6 CHC were enrolled, among whom 529 received treatment; 90.9% of these patients had genotype 1 CHC. The data of the full analysis set showed that SVR rate was 69.80% (95% CI 65.00%-74.60%) in the trial group and 74.16% (95% CI 67.73%-80.59%) in the control group (P = 0.297 0). The data of the per protocol set (PPS) showed that SVR rate was 80.63% (95% CI 76.04%-85.23%) in the trial group and 81.33% (95% CI 75.10%-87.57%) in the control group (P = 0.849 8), and the 95% CI of rate difference conformed to the non-inferiority standard. The analysis of the PPS population showed that of all subjects, 47.9% achieved rapid virologic response, with a positive predictive value of 93.8%. The incidence rate of adverse events was 96.30% in the trial group and 94.94% in the control group, and the incidence rate of serious adverse events was 5.13% in the trail group and 5.06% in the control group. Conclusion: In the regimen of Peg-IFN-α combined with ribavirin for the treatment of genotype 1/6 CHC, the new investigational drug Peg-IFN-α-2b(Y shape, 40 kD) has comparable clinical effect and safety to the control drug Peg-IFN-α-2a.

[Current status of occupational health and related countermeasures in Guangzhou, China]

OBJECTIVE

To investigate the current status of occupational health and related countermeasures in Guangzhou, China.

METHODS

Related data were collected from occupational poisoning accident investigation, diagnosis and identification of occupational diseases, and the occupational disease hazard reporting system, and the statistical data of occupational health in Guangzhou were analyzed retrospectively.

RESULTS

The number of enterprises reporting for occupational disease hazards in Guangzhou was 20 890, and the total number of workers was 1 457 583. The number of workers exposed to occupational hazards was 284 233, and the cumulative number of workers with occupational diseases was 1 502. There were many risk factors for occupational diseases in enterprises, and there were a large number of workers with occupational diseases, as well as newly diagnosed cases. From 2001 to 2014, the total number of cases of occupational diseases was 958.

CONCLUSION

The situation for the prevention and control of occupational diseases is grim in Guangzhou. Occupational health supervision and law enforcement should be enhanced, the three-level supervision system should be established and perfected, and the occupational health supervision system with a combination of "prevention, treatment, and protection" should be established and promoted, so as to gradually establish a technical service support system for occupational health.

Diffuse reflectivity measurement using cubic cavity

A method for measuring diffuse reflectivity using cubic cavity based on the variable port fraction method was developed by measuring oxygen P11 line at 762 nm using tunable diode laser absorption spectroscopy. An experimental method to determine the additional path length l0 was presented. We measured the diffuse reflectivity of a cubic cavity with scattering coatings of different thickness. The error of diffuse reflectivity was reduced from 0.004 to 0.0003 when the diffuse reflectivity increased from 0.867(4) to 0.9887(3). A simulation result manifests that the error of diffuse reflectivity has the potential to be further reduced at higher diffuse reflectivity.

Hepatitis B virus subgenotype C2- and B2-associated mutation patterns may be responsible for liver cirrhosis and hepatocellular carcinoma, respectively

The objective of this study was to examine hepatitis B virus (HBV) subgenotypes and mutations in enhancer II, basal core promoter, and precore regions of HBV in relation to risks of liver cirrhosis (LC) and hepatocellular carcinoma (HCC) in Southeast China. A case-control study was performed, including chronic hepatitis B (CHB; n=125), LC (n=120), and HCC (n=136). HBV was genotyped by multiplex polymerase chain reaction and subgenotyped by restriction fragment length polymorphism. HBV mutations were measured by DNA sequencing. HBV genotype C (68.2%) predominated and genotype B (30.2%) was the second most common. Of these, C2 (67.5%) was the most prevalent subgenotype, and B2 (30.2%) ranked second. Thirteen mutations with a frequency >5% were detected. Seven mutation patterns (C1653T, G1719T, G1730C, T1753C, A1762T, G1764A, and G1799C) were associated with C2, and four patterns (C1810T, A1846T, G1862T, and G1896A) were associated with B2. Six patterns (C1653T, G1730C, T1753C, A1762T, G1764A, and G1799C) were obviously associated with LC, and 10 patterns (C1653T, G1730C, T1753C, A1762T, G1764A, G1799C, C1810T, A1846T, G1862T, and G1896A) were significantly associated with HCC compared with CHB. Four patterns (C1810T, A1846T, G1862T, and G1896A) were significantly associated with HCC compared with LC. Multivariate regression analyses showed that HBV subgenotype C2 and C2-associated mutation patterns (C1653T, T1753C, A1762T, and G1764A) were independent risk factors for LC when CHB was the control, and that B2-associated mutation patterns (C1810T, A1846T, G1862T, and G1896A) were independent risk factors for HCC when LC was the control.

Role of natural day-length and temperature in determination of summer and winter diapause in Pieris melete (Lepidoptera: Pieridae)

Under field conditions, the cabbage butterfly, Pieris melete, displays a pupal summer diapause in response to relatively low daily temperatures and gradually increasing day-length during spring and a pupal winter diapause in response to the progressively shorter day-length. To determine whether photoperiod is 'more' important than temperature in the determination of summer and winter diapause, or vice versa, the effects of naturally changing day-length and temperature on the initiation of summer and winter diapause were systematically investigated under field conditions for five successive years. Field results showed that the incidence of summer diapause significantly declined with the naturally increasing temperature in spring and summer generations. Path coefficient analysis showed that the effect of temperature was much greater than photoperiod in the determination of summer diapause. In autumn, the incidence of diapause was extremely low when larvae developed under gradually shortening day-length and high temperatures. The incidence of winter diapause increased to 60-90% or higher with gradually shortening day-length combined with temperatures between 20.0°C and 22.0°C. Decreasing day-length played a more important role in the determination of winter diapause induction than temperature. The eco-adaptive significance of changing day-length and temperature in the determination of summer and winter diapause was discussed.

Identification of sex-specific polymorphic sequences in the goat amelogenin gene for embryo sexing

Amelogenin (AMEL) is a conserved gene located on the sex chromosomes of mammals. It is involved in the formation of enamel, which is the hard, white material that forms the protective outer layer of each tooth. In this study, we first cloned and determined the intron sequences of the goat AMELX and AMELY genes from female and male ear tissues. The polymorphic AMEL alleles were further analyzed by PCR-based RFLP and Southern blot hybridization analyses. Results showed that intron 5 nucleotide sequences of the goat AMELY gene contains multiple deletions/insertions and shares only 48.5% identity to intron 5 of the goat AMELX gene. Based on the polymorphic AMEL intron sequences, a set of sex-specific triplex primers was designed to PCR amplify a single fragment of 264 bp from the X chromosome of female goats and 2 fragments of 264 and 206 bp from the X and Y chromosomes, respectively, of male goats. An increased sensitivity for sex determination was reached with a single blastomere at the blastula stage isolated from goat embryos. A total of 43 goat embryos were used to estimate a 100% accuracy rate of this method confirmed by chromosomal karyotyping and live births. The embryo sexing technique has been successfully applied in different strains of goats including Alpine, Saanen, Nubian, and Taiwan goats.

Application of high-frequency ultrasound for the detection of surgical anatomy in the rodent abdomen

Rats are used extensively in abdominal disease research. To monitor disease progress in vivo, high-frequency ultrasound (HFU) can be a powerful tool for obtaining high-resolution images of biological tissues. However, there is a paucity of data regarding the correlation between rat anatomy and corresponding HFU images. Twenty-four adult male Sprague-Dawley (SD) rats underwent abdominal scans using HFU (40 MHz) surgical procedures to identify abdominal organs and major vessels as well as in situ scanning to confirm the imaging results. The results were compared with those of human abdominal organs in ultrasonographic scans. The rat liver, paired kidneys, stomach, intestines, and major blood vessels were identified by HFU and the ultrasonic morphologies of the liver and kidneys showed clear differences between rats and humans. Clinically relevant anatomical structures were identified using HFU imaging of the rat abdomen, and these structures were compared with the corresponding structures in humans. Increased knowledge with regard to identifying the anatomy of rat abdominal organs by ultrasound will allow scientists to conduct more detailed intra-abdominal research in rodents.

Development and validation of an improved Bradford method for determination of insulin from chitosan nanoparticulate systems

CONTEXT

Blank chitosan nanoparticles are currently used as reference for the calibration curve, which fails to resolve the supernatant of the nanoparticles in the interference of Coomassie Brilliant Blue G-250 reagent; supernatants are generated at different chitosan nanoparticulate prescriptions, which have different interferences. There are notable errors in the experimental results, and the method is not feasible.

OBJECTIVE

In this study, an improved, rapid, and economic Bradford method was developed and validated.

MATERIALS AND METHODS

The pH of the supernatant of blank chitosan nanoparticles was adjusted to 7-9 through adding saturated NaOH. The precipitation (free chitosan) in the solution was separated by centrifuging for about 10 min (4000 r/min).

RESULTS

The method eliminated the interference of free chitosan of different prescriptions. The results showed that the method presented a linearity in the range of 50-300 microg/mL (R(2) = 0.9992), and possessed a good inter-day and intra-day precision based on relative standard deviation values (less than 3.10%). Recovery of the supernatant of blank chitosan nanoparticles was between 98.30 and 99.93%, and the recovery of blank chitosan nanoparticles was between 95.57 and 100.27%.

DISCUSSION AND CONCLUSION

The method was further tested for determination of the association efficiency of insulin to nanoparticulate carriers composed of chitosan. Encapsulant release under simulated gastrointestinal fluids was evaluated.

Simultaneous detection of multiple-gas species by correlation spectroscopy using a multimode diode laser

Simultaneous detection of multiple-gas species has for the first time (to our knowledge) been demonstrated by using a multimode diode-laser-based correlation spectroscopy (MDL-COSPEC) scheme. Concentration measurements of a mixture of CO(2) and CO gas were performed by probing overlapping line spectra around 1.57microm using an MDL. Species identification and corresponding quantitive analysis were implemented by correlating the recorded absorption signals of the sample gas mixtures with those of the reference gases of particular interest, attaining accuracies of 2% and 1%, respectively. MDL-COSPEC is a generic technique with potential application for simultaneous detection of multiple gases having resolvable narrow lines.

The physiological role of pre- and postsynaptic GABA(B) receptors in membrane excitability and synaptic transmission of neurons in the rat's dorsal cortex of the inferior colliculus

In the inferior colliculus (IC), GABAergic inhibition mediated by GABA(A) receptors has been shown to play a significant role in regulating physiological responses, but little is known about the physiological role of GABA(B) receptors in IC neurons. In the present study, we used whole-cell patch clamp recording in vitro to investigate the effects of activation of GABA(B) receptors on membrane excitability and synaptic transmission of neurons in the rat's dorsal cortex of the inferior colliculus (ICD). Repetitive stimulation of GABAergic inputs to ICD neurons at high frequencies could elicit a slow and long-lasting postsynaptic response, which was reversibly abolished by the GABA(B) receptor antagonist, CGP 35348. The results suggest that postsynaptic GABA(B) receptors can directly mediate inhibitory synaptic transmission in ICD. The role of postsynaptic GABA(B) receptors in regulation of membrane excitability was further investigated by application of the GABA(B) receptor agonist, baclofen. Baclofen hyperpolarized the cell, reduced the membrane input resistance and firing rate, increased the threshold for generating action potentials (APs), and decreased the amplitude of the AP and its associated after-hyperpolarization. The Ca2+-mediated rebound depolarization following hyperpolarization and the depolarization hump at the beginning of membrane depolarization were also suppressed by baclofen. In voltage clamp experiments, baclofen induced inward rectifying K+ current and reduced low- and high-threshold Ca2+ currents, which may account for the suppression of membrane excitability by postsynaptic GABA(B) receptors. Application of baclofen also reduced excitatory synaptic responses mediated by alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors, and inhibitory synaptic responses mediated by GABA(A) receptors. Baclofen increased the ratios of 2nd/1st excitatory and inhibitory postsynaptic currents to paired-pulse stimulation of the synaptic inputs. These results suggest that fast glutamatergic and GABAergic synaptic transmission in ICD can be modulated by presynaptic GABA(B) receptors.

Baculovirus-derived hemagglutinin vaccine protects chickens from lethal homologous virus H5N1 challenge

Since outbreaks of highly pathogenic avian influenza (HPAI) in both human and poultry from 2003, it is critical to have effective vaccines. A cDNA fragment coding the entire hemagglutinin (HA) gene derived from an H5N1 strain (A/duck/China/E319-2/03) was cloned and expressed using the baculovirus system. Two weeks after receiving two doses of recombinant HA (rHA) vaccines, chickens develop high antibody response for hemagglutination inhibition (HI) at titer 7.2 log(2). Challenge studies revealed that vaccinated chickens with HI titers greater than 3 log(2) could have immunoprotection against the same HPAI H5N1 strain virus challenge through intranasal route. Additionally, HI titer of 5 log(2) determined whether the live viruses could not be detected from oropharyngeal, cloacal discharge or in tissues. This result suggests that the rHA expressed from baculovirus system could be a candidate for the development of a safe and efficient subunit vaccine for HPAI (H5N1).

Modification of membrane excitability of neurons in the rat's dorsal cortex of the inferior colliculus by preceding hyperpolarization

The inferior colliculus (IC) is among the largest nuclei in the central auditory system and is considered to be a major integration center in the auditory pathway. To understand how IC contributes to auditory processing, we investigated the effects of preceding hyperpolarization on membrane excitability and firing behavior of neurons located in the dorsal cortex of the inferior colliculus (ICD). We made whole-cell patch clamp recordings from ICD neurons (n=96) in rat brain slices. We classified ICD neurons into three types, i.e. sustained-regular, sustained-adapting and buildup, according to their responses to depolarizing current injection. Nearly 91% of the neurons had sustained firing throughout the period of current injection, showing either regular or adapting pattern. About 9% of the neurons exhibited a buildup pattern, in which sustained firing started after a long delay. Rebound depolarization and spikes after hyperpolarization were seen in 51.7% of the sustained neurons, but were not seen in buildup neurons. When depolarizing current was preceded by a hyperpolarizing current, various forms of the modification on membrane excitability were observed. For non-rebound neurons, the membrane excitability was either suppressed or unchanged after pre-hyperpolarization. The first spike latency lengthened in neurons whose firing changed to a buildup pattern, shortened in those whose firing changed to a pauser pattern, and remained unchanged in those whose discharge pattern remained sustained. For rebound neurons, the firing rate decreased in neurons whose firing pattern was changed to onset or pauser, increased in neurons whose firing was changed to adapting, or remained unchanged in neurons whose firing became irregular. The first spike latency was shortened in all the rebound cells. The results suggest that intrinsic membrane properties can play an important role in integration of excitatory and inhibitory inputs and thereby in determination of the output of ICD neurons.

Sesquiterpene lactones from Saussurea alata

Two new guaianolides, namely, 3beta,8alpha-dihydroxy-13-methoxyl-4(14),10(15)-dien-(1alphaH,5alphaH,6beta H,11betaH)-12,6-olide (1) and 3beta,8alpha-dihydroxy-13-methoxyl-4(14),10(15)-dien-(1alphaH,5alphaH,6beta H,11alphaH)-12,6-olide (2), together with six known guaianolides, 8-hydroxyzaluzanin C, austricin, chlorojanerin, cynaropicrin, chlorohyssopifolin E and chlorohyssopifolin A were isolated from the aerial parts of Saussurea alata. The structures were established mainly based on spectral analysis, especially 2D NMR techniques.

Neurotrophin signaling: many exciting surprises!

Neurotrophins are growth factors implicated in the development and maintenance of different neuronal populations in the nervous system. Neurotrophins bind to two sets of receptors, Trk receptor tyrosine kinases and the p75NTR receptor, to activate several different signaling pathways that mediate various biological functions. While Trk receptor activation has been well-studied and triggers the well-characterized Ras/Rap-MAPK, PI3K-Akt, and PLCgamma-PKC cascades, p75NTR signaling is more complex, and its in vivo significance has not yet been completely determined. In the last few years, p75NTR has received much attention mainly due to recent findings describing pro-neurotrophins as new ligands for the receptor and the ability of the receptor to form different complexes with other transmembrane proteins. This review will update the neurotrophin signaling pathways known for Trk receptors to include newly identified Trk-interacting molecules and will address surprising new findings that suggest a role for p75NTR in different receptor complexes and functions.

CeO2 Nanorods and Gold Nanocrystals Supported on CeO2 Nanorods as Catalyst

The formation mechanism of uniform CeO2 structure at the nanometer scale via a wet-chemical reaction is of great interest in fundamental study as well as a variety of applications. In this work, large-scale well-crystallized CeO2 nanorods with uniform diameters in the range of 20-30 nm and lengths up to tens of micrometers are first synthesized through a hydrothermal synthetic route in 5 M KOH solution at 180 degrees C for 45 h without any templates and surfactants. The nanorod formation involves dehydration of CeO2 nanoparticles and orientation growth along the 110 direction in KOH solution. Subsequently, gold nanoparticles with crystallite sizes between 10 and 20 nm are loaded on the surface of CeO2 nanorods using HAuCl4 solution as the gold source and NaBH4 solution as a reducing agent. The synthesized Au/CeO2 nanorods demonstrate a higher catalytic activity in CO oxidation than the pure CeO2 nanorods.

Presynaptic modulation of GABAergic inhibition by GABA(B) receptors in the rat's inferior colliculus

Whole-cell patch clamp recordings were made from neurons in a brain slice preparation of the inferior colliculus in 11-15-day-old rat pups. Synaptic responses were elicited by applying a current pulse to the lateral lemniscus just below the central nucleus of the inferior colliculus. To examine GABAergic inhibition in the inferior colliculus all excitatory postsynaptic potentials and glycinergic inhibitory postsynaptic potentials were blocked by bath application of their respective antagonists and the contribution of GABA(B) receptors was determined for the remaining inhibitory postsynaptic potentials. For most cells the isolated inhibitory postsynaptic potential was completely blocked by the GABA(A) receptor antagonist, bicuculline, but was unaffected by the GABA(B) receptor antagonist, phaclofen. The GABA(B) receptor agonist, baclofen (10-20 microM), decreased the amplitude of the inhibitory postsynaptic potentials. This effect was completely blocked by phaclofen. Baclofen did not increase the cell membrane conductance or alter the rate of firing produced by depolarization of the cell membrane. In contrast, muscimol, a GABA(A) receptor agonist, greatly increased membrane conductance and lowered the firing rate produced by depolarization. Our results indicate that GABAergic inhibition in the auditory midbrain can be reduced by the activation of GABA(B) receptors and suggest that the effects are presynaptic.

Genotype and allele frequency of the 27-bp tandem repeat polymorphism in the endothelial nitric oxide synthase gene in Chinese population

Genotype and allele frequency of the polymorphic 27-bp repeat, a variable number of tandem repeats (VNTR) located in intron 4 of the endothelial nitric oxide synthase gene, were analyzed in 316 healthy Chinese individuals. Four genotypes, namely 6/5-repeats heterozygous, 5/5-repeats homozygous, 5/4-repeats heterozygous and 4/4-repeats homozygous, were identified. Both observed genotype and allele frequencies of this VNTR in Chinese were similar to those of Japanese, while the 4/4-repeats genotype differed significantly from that of Caucasians in Spain, and all ones did from those of African-American in United States.

Symmetrical body-weight distribution training in stroke patients and its effect on fall prevention

OBJECTIVE

To determine the role of symmetrical body-weight distribution training in preventing falls among patients with hemiplegic stroke.

DESIGN

A prospective study using a standing biofeedback trainer.

SETTING

Hospital-based rehabilitation units.

PATIENTS

Fifty-four patients with hemiplegic stroke (30 in the training group, 24 in the control group).

INTERVENTIONS

Conventional stroke rehabilitation program, plus symmetrical standing training and repetitive sit-to-stand training, with a standing biofeedback trainer. Training effect was evaluated by assessing the sit-to-stand performance and comparing the occurrence of falls in the 2 groups at a 6-month follow-up.

MAIN OUTCOME MEASURES

Occurrence of falls, sit-to-stand performance, including body-weight distribution, rate of rise in force, and sway in center of pressure (COP).

RESULTS

Significant improvement in sit-to-stand performance was found in patients in the training group. Body weight was distributed more symmetrically in both legs, with less mediolateral sway in the COP when rising and sitting down. The mean difference in body-weight distribution between the left and right legs while subjects were rising from a chair significantly decreased, from 49.5% +/- 18.9% to 38.6% +/- 15.8% of body weight (BW) (p < .005). The rate of rise in force while rising from a chair significantly increased, from 28.3% +/- 13.5%BW/s to 53.6% +/- 20.5%BW/s (p < .001). At the 6-month follow-up, 10 of 24 patients (41.7%) in the control group had fallen, compared with only 5 of 30 patients (16.7%) in the training group (p < .05).

CONCLUSIONS

Symmetrical body-weight distribution training may improve sit-to-stand performance and, consequently, decrease the number of falls by stroke patients.

Cloning, sequencing, heterologous expression, purification, and characterization of adenosylcobalamin-dependent D-ornithine aminomutase from Clostridium sticklandii

D-Ornithine aminomutase from Clostridium sticklandii catalyzes the reversible rearrangement of d-ornithine to (2R,4S)-2,4-diaminopentanoic acid. The two genes encoding d-ornithine aminomutase have been cloned, sequenced, and expressed in Escherichia coli. The oraS gene, which encodes a protein of 121 amino acid residues with M(r) 12,800, is situated upstream of the oraE gene, which encodes a protein of 753 amino acid residues with M(r) 82,900. The holoenzyme appears to comprise a alpha(2)beta(2)-heterotetramer. OraS shows no significant homology to other proteins in the Swiss-Prot data base. The deduced amino acid sequence of OraE includes a conserved base-off/histidine-on cobalamin-binding motif, DXHXXG. OraE was expressed in E. coli as inclusion bodies. Refolding experiments on OraE indicate that the interactions between OraS and OraE and the binding of either pyridoxal phosphate or adenosylcobalamin play important roles in refolding process. The K(m) values for d-ornithine, 5'-deoxyadenosylcobalamin (AdoCbl), and pyridoxal 5'-phosphate (PLP) are 44.5 +/- 2.8, 0.43 +/- 0.04, and 1.5 +/- 0.1 microm, respectively; the k(cat) is 6.3 +/- 0.1 s(-1). The reaction was absolutely dependent upon OraE, OraS, AdoCbl, PLP, and D-ornithine being present in the assay; no other cofactors were required. A red-shift in UV-visible absorption spectrum is observed when free adenosylcobinamide is bound by recombinant D-ornithine aminomutase and no significant change in spectrum when free adenosylcobinamide is bound by mutant OraE-H618G, demonstrating that the enzyme binds adenosylcobalamin in base-off/histidine-on mode.

Solution structure of a Kunitz-type chymotrypsin inhibitor isolated from the elapid snake Bungarus fasciatus

Bungarus fasciatus fraction IX (BF9), a chymotrypsin inhibitor, consists of 65 amino acid residues with three disulfide bridges. It was isolated from the snake venom of B. fasciatus by ion-exchange chromatography and belongs to the bovine pancreatic trypsin inhibitor (BPTI)-like superfamily. It showed a dissociation constant of 5.8 x 10(-8) m with alpha-chymotrypsin as measured by a BIAcore binding assay system. The isothermal titration calorimetry revealed a 1:1 binding stoichiometry between this inhibitor and chymotrypsin and apparently no binding with trypsin. We further used CD and NMR to determine the solution structure of this venom-derived chymotrypsin inhibitor. The three-dimensional NMR solution structures of BF9 were determined on the basis of 582 restraints by simulated annealing and energy minimization calculations. The final set of 10 NMR structures was well defined, with average root mean square deviations of 0.47 A for the backbone atoms in the secondary structure regions and 0.86 A for residues The side chains of Phe(23), Tyr(24), Tyr(25), Phe(35), and Phe(47) exhibited many long-range nuclear Overhauser effects and were the principal components of the hydrophobic core in BF9. To gain insight into the structure-function relationships among proteins in the BPTI-like superfamily, we compared the three-dimensional structure of BF9 with three BPTI-like proteins that possess distinct biological functions. These proteins possessed similar secondary structure elements, but the loop regions and beta-turn were different from one another. Based on residues at the functional site of each protein, we suggest that the flexibility, rigidity, and variations of the amino acid residues in both the loop and beta-turn regions are related to their biological functions.

Isolation and characterization of an active compound from black soybean [Glycine max (L.) Merr.] and its effect on proliferation and differentiation of human leukemic U937 cells

Black soybean [Glycine max (L.) Merr.] has been used as a health food and herb in China for hundreds of years. In the present study, we purified a unique polysaccharide component from black soybean (PSBS) and found that it indirectly inhibits proliferation and induces differentiation of human leukemic U937 cells via activation of mononuclear cells (MNCs). We prepared conditioned media (MNC-CM) by incubating MNCs from human peripheral blood with or without PSBS (PSBS-MNC-CM and normal MNC-CM, respectively). Treatment of human leukemic U937 cells with PSBS-MNC-CM significantly inhibited proliferation of U937 cells, reducing their growth by 98.5%. Furthermore, PSBS-MNC-CM induced U937 cells to differentiate into mature monocytes/macrophages (83% by morphological examination and 90% by the nitroblue tetrazolium test). Neither PSBS alone nor normal MNC-CM had such effects. The molecular weight of PSBS was about 480 000 by gel filtration. Structural analysis of PSBS revealed that (1,6)-alpha-D-glucan might be its major active component. Our results suggest that the PSBS may inhibit proliferation and induce differentiation in human leukemic U937 cells by activating the immune response of MNCs.

Multifunctionalized alpha,beta-cyclopentenones from C-2 and C-4-ulopyranosyl compounds: a stereospecific rearrangement initiated by base

Base treatment of O-benzyl protected C-2- or C-4-ulopyranosyl compounds (4 alpha, 4 beta, and 11) by either 10% Et(3)N or 1% K(2)CO(3) in MeOH initiated a beta elimination to afford alpha,beta-unsaturated C-ulopyranosyl compounds (5 alpha, 5 beta, and 12), which further rearranged in a stereocontrolled manner to multifuctionalized alpha,beta-cyclopentenones (6 and 14) in 70-80% yield. Both C-alpha- and C-beta-2-ulosides (5 alpha and 5 beta) produced the same cyclopentenone 6, indicating that a 1,2-enolate is formed prior to the cleavage of the C-5--O bond. Because 6 is racemic, it was probably formed by the intramolecular cycloaldolization of two equally populated enantiomeric intermediates. When treated with 90% Et(3)N in MeOH, 5 alpha yielded almost exclusively 15 (isomer of 6), which was formed by a migration of the double bond in 5 alpha during the previously described rearrangement. Thus either 6 or 15 was the major product, depending on the base used.

Sesquiterpenoids from Magnolia grandiflora

Three new sesquiterpenoids were obtained from the leaves of Magnolia grandiflora L. Their structures were determined as 6 alpha,11-dihydroxy-12,13-diacetoxyelem-1,3-diene, 4 alpha,6 alpha,10 alpha-trihydroxy-13-acetoxyguaia-11-ene, and 12,13-diacetoxyguaia-4 alpha,6 alpha,10 alpha,11-tetraol on the basis of spectral evidence. In addition, the known sesquiterpenoid magnograndiolide was also obtained.

Simultaneous analysis of enantiomeric composition of amino acids and N-acetyl-amino acids by enantioselective chromatography

Among the three chiral columns, CHIROBIOTIC T, CHIRLPAK WH, and CHIRALCEL OD-R, tested for the separation of racemic amino acids and N-acetyl-amino acids, only CHIROBIOTIC T chiral column which is based on covalently bonded amphoteric glycopeptide, teicoplanin, as the stationary phase ligand could be successfully developed to enantiomerically separate racemic amino acids and N-acetyl amino acids simultaneously. This method can be used to determine the enantiomeric composition of amino acids and N-acetyl-amino acids in the catalysis of D-aminoacylase or L-aminoacylase and the conversion rate of N-acylamino acid racemases.

ent-Pimarane derivatives from Dysoxylum hainanense

Four ent-pimarene diterpenoids. ent-18-acetoxy-8(14)-pimarene-15S, 16-diol, ent-18-acetoxy-16-hydroxy-8(14)-pimaren-15-one, ent-16,18-dihydroxy-8(14)-pimaren-15-one and ent-19-nor-4,16,18-trihydroxy-8(14)-pimaren-15-one, together with three known damarane triterpenoids, richenoic acid, eichleriainic acid and shoreic acid were isolated from the bark of Dysoxyhum hainanense Merr. Their structures were elucidated on the basis of spectroscopic techniques. The absolute configurations of four diterpenoids were assigned as ent-pimarene type by chemical transformation and by co-occurrence in the plant as well as by negative optical rotations for four compounds.

[Structural and functional study of prokaryotic enhancer-like element VV1 from vaccinia virus]

Enhancer VV1 (about 283 bp) is selected as the target to analyze its structure and function systemically. Stepwise deletion experiment is used to identify the functional domain of VV1 element. The results suggest that the 20 bp at 5' terminal and 20 bp at 3' terminal are important to the activity of VV1, for without either of them its activity decreased greatly. Furthermore, the 30-50 bp at 5' terminal is essential to its activity, without which will lead to complete loss of its activity. By random mutagenesis assay it is found that base mutation can regulate the activity of enhancer VV1 positively or negatively. The more the activities of mutants descend, the more mutations take place. For singlebase mutation, the activities change relatively little, and most of the mutations always occur in the 50 bp at the 5' terminal.

Morphology and physiology of neurons in the ventral nucleus of the lateral lemniscus in rat brain slices

The ventral nucleus of the lateral lemniscus (VNLL) is a prominent neuronal group that lies within the auditory pathway connecting the auditory lower brainstem and midbrain. Previous physiologic studies showed that VNLL neurons respond mainly to contralaterally presented sounds and display various firing patterns. To understand better the role that VNLL neurons play in transmitting and processing of auditory information, we examined the morphology of VNLL neurons and their cellular physiology in young rat brain slices. We made whole-cell patch-clamp recordings and labeled cells intracellularly with neurobiotin to investigate the relation between morphologic neuronal types, intrinsic membrane properties, and postsynaptic responses. VNLL neurons fell into two distinct morphologic groups, i.e., bushy cells and stellate cells, based on their dendritic patterns. Stellate cells were grouped further into stellate I, II, and elongate cells according to soma shape, dendritic branches, and orientation. Bushy cells showed an onset firing pattern and a nonlinear current-voltage relationship. All three subtypes of stellate cells had a linear current-voltage relationship, but exhibited different firing patterns. Stellate I cells showed regular and onset-pause firing patterns, whereas stellate II cells showed adapting and elongate cells showed burst firing patterns. Bushy cells and stellate cells responded to stimulation of the lateral lemniscus with excitatory and/or inhibitory synaptic potentials. These results suggest that the VNLL is a heterogeneous neuronal group and that it contains many channels for processing different kinds of auditory information. Neuronal morphology and intrinsic membrane properties contribute to the behavior of individual neurons.