Peptidergic innervation of human esophageal and cardiac carcinoma

AIM: To investigate the distribution of neuropeptide-immunoreactive nerve fibers in esophageal and cardiacca rcinoma as well as their relationship with tumor cells so as to explore if there is nerve innervation in esophageal and cardiac carcinoma.METHODS: Esophageal and cardiac carcinoma specimens were collected from surgical operation. One part of them were fixed immediately with 4 % paraformaldehyde and then cut with a cryostat into 40-μm-thick sections to perform immunohistochemical analysis. Antibodies of ten kinds of neuropeptide including calcitonin gene-related peptide(CGRP), galanin (GAL), substance P (SP), etc. were used for immunostaining of nerve fibers. The other part of the tumor specimens were cut into little blocks (1 mm^3) and cocultured with chick embryo dorsal root ganglia (DRG) to investigate if the tumor blocks could induce the neurons of DRG to extend processes, so as to probe into the possible reasons for the nerve fibers growing into tumors.RESULTS: Substantial amounts of neuropeptide including GAL-, NPY-, SP-immunoreactive nerve bundles and scattered nerve fibers were distributed in esophageal and cardiac carcinomas. the scattered nerve fibers waved their way among tumor cells and contacted with tumor cells closely. Some of them even encircled tumor cells. There were many varicosities aligned on the nerve fibers like beads. They were also closely related to tumor cells. In the co-culture group, about 63 % and 67 % of DRG co-cultured with esophageal and cardiac tumor blocks respectively extended enormous processes,especially on the side adjacent to the tumor, whereas in the control group (without tumor blocks), no processes grew out.CONCLUSION: Esophageal and cardiac carcinomas may be innervated by peptidergic nerve fibers, and they can induce neurons of DRG to extend processes in vitro.     

Gene expression and antitumor effect following imelectroporation delivery of human interferon α2 gene

AIM: To investigate the gene expression and antitumor effect following im electroporation delivery of human interferon alpha 2 (hIFN-alpha 2) gene. METHODS: The pcD2/hIFN-alpha 2 was injected into the middle of the quadriceps muscle of female BALB/c mice or the leukemia-bearing female BALB/c nude mice, and then electroporation was given to the injection site. Optimal electrical parameters and the efficiency of gene transfer was studied with hIFN-alpha 2 ELISA kit. The HL-60 tumor model in BALB/c nude mice was used to investigate therapeutic effects of im electroporation delivery of pcD2/hIFN-alpha 2. RESULTS: The optimal conditions for the electric pulses were as follows: voltage at 200 V/cm; pulse duration at 40 ms per pulse; number of pulse at 6 pulses and frequency at 1 Hz. Under optimal conditions, the serum hIFN-alpha 2 levels in electroporation group (160 microg/L+/-31 microg/L) were 45-fold higher than those of nonelectroporation group (3.6 microg/L+/-1.6 microg/L, P<0.01). The growth of leukemia was inhibited more obviously and the survival time of the leukemia-bearing nude mice was prolonged after im electroporation delivery of pcD2/hIFN-alpha 2 100 microg or 200 microg. CONCLUSION: Electroporation was an efficient method for the delivery of plasmid DNA and im electroporation delivery of pcD2/hIFN-alpha 2 was effective in treating leukemia.     

Folpet permeation through nitrile gloves

The aim of this study was to investigate whether two different brands of unsupported and unlined nitrile gloves protected against aqueous emulsions of a Folpet wettable powder (50% Folpet) using an ASTM type-I-PTC 600 permeation cell at 30.0 +/- 0.1 degrees C held in a shaking water bath. An analytical method to determine Folpet using the internal standard method was first developed based on gas chromatography-mass spectrometry (GC-MS), and gas chromatography-electron capture detection (GC-ECD). A novel pyrolysis GC-ECD technique that quantified the thermal degradation product phthalimide had pg sensitivity suitable to detect the trace amounts of Folpet that permeated. The on-column conversion was (68.0 +/- 9.5) percent at 170 degrees C over the folpet injected mass range of 3 to 148 pg. The challenge solution in the permeation cell was 1.4 mg/mL aqueous emulsion of Folpet wettable powder, and 2-propanol was the collection solvent. After evaporation of the collection solvent, the time weighted average rate of permeation of Folpet through SafeSkin nitrile (an exams type of glove) after 8 hours was (42.1 +/- 2.9) ng/cm(2)/min compared with (2.04 +/- 0.69) ng/cm(2)/min for the Sol-Vex nitrile (industrial chemical resistant), the latter being about 21 times more protective and also near the limits of detection. The respective values after 4 hours of exposure were (28.4 +/- 1.2) and (0.65 +/- 0.36) ng/cm(2)/min. Diagnostic reflectance infrared minima of both challenge and collection sides of the gloves showed small changes in wave number and intensity values after 8 hours of exposure, with Folpet being detected in dried spots on the challenge side. GC-ECD-based permeation and IR reflectance data indicated high chemical resistance of the Sol-Vex gloves to an aqueous emulsion of Folpet.     

Chronic cardiac allograft rejection in a rat model disparate for one single class I MHC molecule is associated with indirect recognition by CD4(+) T cells

T-cell mediated immune responses play a critical role in chronic allograft dysfunction. The complex nature of allograft rejection, particularly with respect to the vast repertoire of alloantigens and their mode of recognition by T cells, presents a major challenge for the design of well-controlled studies into the immunobiology of chronic rejection. The purpose of this study was to develop a rat model with restricted antigenic specificity that develops chronic rejection without any immunologic manipulation to study the T-cell response. PVG.1U allogeneic hearts disparate for one single class I antigen, RT.1A(u), were transplanted into PVG.R8 rat recipients. Grafts from PVG.R8 were used as syngeneic controls. Chronic rejection was studied by histological analysis of the grafted hearts at various time points posttransplantation (20-100 days). Donor specific alloreactive response was studied in a mixed lymphocyte reaction assay. All allografts survived more than 90 days and showed extensive evidence of chronic rejection, which was characterized by interstitial fibrosis, vasculitis, and occlusive myointimal thickening. Chronic rejection was evident by day 20 and most extensive by day 100 posttransplantation. In marked contrast, syngeneic grafts remained free of chronic lesions. Lymphocytes harvested from graft recipients showed a more vigorous proliferative response to allogeneic splenocytes as compared with that of lymphocytes from nai;ve animals. The proliferative response was primarily mediated by CD4(+) T cells recognizing the RT1.A(a) molecule via the indirect pathway. A single class I disparity in this model generates chronic rejection associated with potent CD4(+) T-cell responses induced by the indirect recognition pathway. The use of this antigenically restricted model may facilitate the design of well-controlled studies for the characterization of immune mechanisms responsible for chronic rejection.     

蛋白激酶C抑制剂对精氨酸升压素调控心脏成纤维细胞增殖及p27蛋白表达的影响

目的　观察蛋白激酶C(PKC)抑制剂白屈菜红 (chelerythrine)对精氨酸升压素 (AVP)介导的心脏成纤维细胞 (CF)增殖及p2 7蛋白表达的影响 ,探讨AVP促CF增殖的细胞内信号传导机制。方法　以培养的新生SD大鼠CF为实验模型 ,实验分 3组基础状态组 ;10 -7mol/LAVP组 ;10 -7mol/LAVP +10 -6mol/L白屈菜红组。每组 4只SD大鼠。采用胰酶消化、差速贴壁法培养CF ,四氮唑盐(MTT)比色法检测细胞增殖 ,碘化丙啶标记细胞DNA、p2 7蛋白的单抗和标记了FITC的二抗标记细胞内的p2 7蛋白 ,采用流式细胞分析仪 (FCM)技术测定细胞周期及p2 7蛋白表达的阳性率。结果　 ( 1)10 -7mol/LAVP和 10 -6mol/L白屈菜红共同作用 48h ,MTT比色法测定的CF的A值 ( 0 32± 0 0 1)明显低于 10 -7mol/LAVP组 ( 0 39± 0 0 1,P <0 0 1) ;( 2 )AVP与白屈菜红共同作用组CF的S期细胞百分率 ( 4 4%± 1 7% )和细胞增殖指数 ( 2 0 9%± 1 2 % )分别明显低于AVP组 ( 15 5 %± 1 4%和31 4%± 1 5 % ) ,而G0 /G1期细胞百分率 ( 79 1%± 1 2 % )明显高于AVP组 ( 6 8 6 %± 1 5 % ) ,两组间比较差异有非常显著意义 (P <0 0 1) ;( 3)AVP与白屈菜红共同作用组CF的p2 7蛋白表达阳性率( 91 7%± 2 2 % )明显高于AVP单独作用组 ( 6 3 3%± 1 9% ) ,二     

Surface sampling for a pesticide in dust and small spills of a solid dye

The aim was to determine whether a published sampling technique for loose soil on hard surfaces achieved acceptable efficiency at surface dust/soil coverages of 10-20 mg/ 100 cm2. The sampler was a cordless personal sampling pump operated at 4.0 L/min connected to a cassette containing a filter, the cassette being also connected to a Tygon sampling probe that was moved manually on the surface to be sampled. Rhodamine 6G dye dust was evaluated at 10 mg/100 cm2 coverage at flow rates of 1.0-4.0 L/min. Two National Institute of Standards and Technology (NIST) standard reference materials (SRMs) were used for pesticide experiments: SRM 2711 Montana Soil, and SRM 1649a Urban Dust. The efficiencies for these SRMs were determined uncoated, and coated with 1300 microg chlorpyrifos/g as a Lorsban 4E emulsifiable concentrate formulation. The 3-pass technique sampled both the pesticide-coated and uncoated dust and soil at >79 percent efficiency and at better than 16 percent coefficient of variation (CV) above 15 mg collected mass. Sampling at 20 mg/100 cm2 coverage lowered the CV to < or = 7.1 percent. The dye was sampled with similar efficiency > or = 1.5 L/min, but the CV for the 3-pass technique was <10 percent at 1.5-2.0 L/min, and <20 percent at 1.5-4.0 L/min. The efficiency for a 5-pass technique for the dye exceeded 90 percent at > 1.5 L/min with CVs < 10 percent at 1.5, 2.0, 2.5, and 3.5 L/min. The weight change of the sampling probe and the cassette must be measured for accurate determination of low surface coverages rather than just the weight change of the filter alone. The method allows use of personal sampling equipment for aerosols to measure low coverages of loose dust, soil, and chemical solids on hard surfaces.     

Evaluation of five commercial serological tests for the detection of Helicobacter pylori infection in Chinese

BACKGROUND: Commercial serological tests for the detection of Helicobacter pylori infection must be locally validated. We evaluated the accuracy of five commercial tests in the Chinese population. METHODS: Serum samples were collected from patients referred for upper endoscopy. Antral biopsies were taken for histological examination and culture of H. pylori. The gold standard for diagnosing H. pylori infection was positive histological staining and/or positive H. pylori culture. The serum samples were tested for H. pylori antibodies using the following tests: (i) Cobas Core Anti-H. pylori EIA; (ii) GAP IgG; (iii) GAP IgM; (iv) H. pylori microwell EIA (Quidel); and (v) Premier H. pylori. The sensitivity, specificity and accuracy of each test was calculated according to the manufacturers' instructions or according to a new cut-off value. RESULTS: A total of 158 patients were recruited amongst whom 114 (72%) were H. pylori-positive. Indeterminate results varied from 7% to 19%. The accuracy of the tests varied from 57% to 85%. By using new cut-off values, the accuracy was much improved, ranging from 73.4% to 86.7%. CONCLUSIONS: By defining new cut-off values for the Chinese population, we were able to improve the performance of some of the serology tests. This illustrates the importance of local validation.     

<基本认知能力要素测试系统>的编制与信度、效度分析

目的：建立一种新型的认知能力评价系统,用其进行重复测查时能有效地避免（消除）学习效应．方法：采用普遍认可的量表,根据随机化原则编制计算机化测试系统,该系统与研究任务和对象相适应,测试程序规范,测试项目较多并可任意选择和组合,测试结果记录自动化．为用户提供一种方便友善的人机界面．结果：５４名受试者相隔２ｗｋ的重测可靠性第数为０．６２￣０．８５,符合设计要求;分半信度系数为０．６５￣０．８４,表明测试     

Effect of Dust on the Viability of Vibrio fischeri in the Microtox Test

The standard Microtox test involving the bioluminescent bacterium Vibrio fischeri is a frequently used ecotoxicological bioassay whose EC₅₀ values have been correlated to acute toxicity parameters of vertebrates, to irritancy measures, and to cytotoxicity indices. The aims were to explore the dependence of light output on viable cell number, with the latter estimated with the naked eye using a colorimetric tetrazolium salt method, the effects of dust on the bioluminescence and cell viability, how the viability of the cells is affected after spills, and how spills can be sampled. The lower limit of the linear dynamic range of the light-emitting bacterium was first defined to be 3.7×10⁷ cells/mL, compared with 37×10⁷ cells/mL in the Microtox assay. The effects of dust were then explored in the working range by the method of standard additions by adding 5-, 10-, and 20-mg amounts of Standard Reference Material Urban Dust 1649a. This simulated dust samples collected by a cordless vacuum technique involving a filter cassette. A mass of 20 mg dust totally inhibited the Microtox test at all times (5, 15, and 30 min). Masses of 5 and 10 mg dust lowered the luminescence significantly by 20 and 64%, respectively, after 30 min. However, the viability test was totally inhibited by 5 mg of dust. A spectrophotometric modification of the viability test using a wavelength of 508 nm was developed that was twice as sensitive as the naked eye test, and was as sensitive as the Microtox test. Mechanical shock involved with spilling and sampling bacterial reagent on hard surfaces killed the luminescent bacteria as shown by inhibition of luminescence. The optimum filter cassette for Microtox reagent collection was a 25-mm 1.00-μm PTFE filter in a 25-mm Delrin holder operated at 4.0 L/min, with a Tygon sampling probe.