桃仁红花煎治疗无症状性高脂血症的作用研究

目的:探讨活血化淤理气通络经典方剂“桃仁红花煎”对无症状性高脂血症的治疗作用。方法:使用ShimadiuCL-7200型自动生化分析仪检测各组治疗前后患者血浆总胆固醇(TC)、甘油三酯(TG)、低密度脂蛋白(LDL)、高密度脂蛋白(HDL)、载脂蛋白A(APoA)、载脂蛋白B(APoB)水平,使用Griess法检测治疗前后患者血浆一氧化氮(NO)水平,使用邻苯三酚法检测血清超氧化物歧化酶(SOD)活性,使用巴比妥法检测血清丙二醛(MDA)含量。结果:治疗后,治疗组患者血浆TC、TG、LDL、MDA水平明显降低(P<0.05),而ApoA、HDL、NO水平,及SOD活性明显升高(P<0.05或P<0.01),APoB治疗前后无明显变化(P>0.05);对照组给予洛伐它丁治疗后,TC、TG、LDL水平明显降低(P<0.05),ApoA、HDL水平明显升高(P<0.05),而MDA、NO、ApoB含量及SOD活性无明显变化。结论:活血化淤理气通络中药可以降低血脂,并有可能防治高脂血症对血管造成损害.     

Clinical Evaluation of Compression Ratios using JPEG2000 on Computed Radiography Chest Images

The efficient compression of radiographic images is of importance for improved storage and network utilization in support of picture archiving and communication systems (PACS) applications. The DICOM Working Group 4 adopted JPEG2000 as an additional compression standard in Supplement 61 over the existing JPEG. The wavelet-based JPEG2000 can achieve higher compression ratios with less distortion than the Discrete Cosine Transform (DCT)-based JPEG algorithm. However, the degradation of JPEG2000-compressed computed radiography (CR) chest images has not been tested comprehensively clinically. The authors evaluated the diagnostic quality of JPEG2000-compressed CR chest images with compression ratios from 5:1 to 200:1. An ROC (receiver operating characteristic analysis) and t test were performed to ascertain clinical performance using the JPEG2000-compressed images. The authors found that compression ratios as high as 20:1 can be utilized without affecting lesion detectability. Significant differences between the original and the compressed CR images were not recognized up to compression ratio of 50:1 within a confidence level of 99%.     

p53 protein overexpression and allele loss of p53 gene in gastric adenocarcinoma.

Gene alterations of p53 tumor suppressor gene such as point mutations, deletions or insertions occur in various human cancers. p53 protein overexpression was studied immunohistochemically in 80 gastric adenocarcinomas using an anti-human p53 antibody (Pab 1801) and the avidin-biotin-peroxidase technique. We have also analyzed allele loss of the human p53 gene in 54 cases of gastric adenocarcinoma using polymerase chain reaction and restriction fragment length polymorphism. p53 immunostaining was also demonstrated in 48 of 80 carcinomas (60%). Normal mucosa was always negative. No relation could be found between p53 immunostaining and the degree of differentiation. 21 of the 54 patients(39%) were informative for the p53 exon 4. In ten of these informative cases(47.6%), tumor DNAs showed allele loss when compared with nonmetastatic lymph node DNAs. Seven of the ten(70%) showed p53 immunoreactivity. These findings suggest that mutations of the p53 gene may play a role in the development of gastric adenocarcinoma and that allele loss of p53 frequently occurs in p53 immunoreactive gastric adenocarcinoma.     

Simultaneous differentiation and typing of Entamoeba histolytica and Entamoeba dispar

Sequences corresponding to some of the polymorphic loci previously reported from Entamoeba histolytica have been detected in Entamoeba dispar. Comparison of nucleotide sequences of two loci between E. dispar strain SAW760 and E. histolytica strain HM-1:IMSS revealed significant differences in both repeat and flanking regions. The tandem repeat units varied not only in sequence but also in number and arrangement between the two species at both the loci. Using the sequences obtained, primer pairs aimed at amplifying species-specific products were designed and tested on a variety of E. histolytica and E. dispar samples. Amplification results were in complete agreement with the original species classification in all cases, and the PCR products displayed discernible size and pattern variations among the isolates.     

Standardization for image characteristics in telemammography using genetic and nonlinear algorithms

As the soft copy reading and computer assisted diagnosis (CAD) in mammography become more and more important, the standardization of digital images becomes paramount. Telemammography and telemedicine requires the standardization for image characteristics, such as image resolution, bit-depth and intensity response. Soft copy reading and CAD in mammography are both dependent on the characteristics of the source of the digital data, either direct digital mammography or digitized screen-film mammography. An algorithm developed on images from one database may not perform well as on images from another database (with a different digitization). In this paper, we describe two methods based on a genetic algorithm and a nonlinear algorithm for standardization of digitized and digital mammography. The proposed standardization techniques are based on geometric and intensity transformations that are discovered using a set of calibration images. A set of transformation algorithm is used to search for the best standardization.     

In vitro inhibition of coronavirus replications by the traditionally used medicinal herbal extracts, Cimicifuga rhizoma, Meliae cortex, Coptidis rhizoma, and Phellodendron cortex.

BACKGROUND: A search for new anti-coronaviral drugs to treat coronaviral infections was motivated by an outbreak of severe acute respiratory syndrome (SARS). OBJECTIVES: In order to find drugs that treat coronavirus infections, including SARS, we screened traditional medicinal herbal extracts and evaluated their antiviral activities on coronavirus replication. STUDY DESIGN: We employed a plaque assay to evaluate the effect of 22 medicinal herbal extracts on virus replication. We determined the 50% effective concentration (EC50) of each extract that was necessary to inhibit the replication of mouse hepatitis virus A59 (MHV-A59); we also determined 50% cytotoxic concentrations (CC50) for each extract. Northern and Western blot analyzes were performed to investigate antiviral activity in MHV-infected DBT cells, including virus entry, viral RNA and protein expression, and virus release. Coronavirus specific inhibition was also demonstrated using porcine epidemic diarrhea virus (PEDV). RESULTS: Cimicifuga rhizoma, Meliae cortex, Coptidis rhizoma, Phellodendron cortex and Sophora subprostrata radix decreased the MHV production and the intracellular viral RNA and protein expression with EC50 values ranging from 2.0 to 27.5 microg/ml. These extracts also significantly decreased PEDV production and less dramatically decreased vesicular stomatitis virus (VSV) production in vitro. CONCLUSIONS: The extracts selected strongly inhibited MHV replication and could be potential candidates for new anti-coronavirus drugs.     

雄激素应答元件陷阱DNA抑制PSA基因启动子的作用并诱导LNCaP细胞凋亡(英)

目的：研究雄激素应答元件陷阱DNA（ARE decoy）对前列腺特异抗原（PSA）基因启动子的抑制作用及其对前列腺癌细胞LNCaP细胞生长活性的影响，为前列腺癌的基因治疗寻求新的策略。 方法:联合运用报告基因和陷阱DNA策略，构建含PSA基因5’侧启动子区640 bp DNA的荧光素酶表达载体pGL3-PSA， ARE陷阱DNA共转染前列腺癌细胞株PC3-M。应用双荧光素酶测定系统，检测荧光素酶的表达活性。然后，应用2 mg/L ARE decoy转染LNCaP细胞，通过相差显微镜观察细胞超微结构变化，MTT比色法检测细胞生长活性，DNA ladder和流式细胞技术（FCM）检测细胞凋亡以研究ARE decoy DNA对前列腺癌细胞LNCaP细胞生长活性的影响。同时提取LNCaP细胞核蛋白，应用电泳迁移率变动分析(EMSA)检测ARE decoy DNA与雄激素受体的特异结合。结果:ARE decoy DNA显著抑制报告基因荧光素酶的表达，抑制率可达95%。EMSA显示ARE decoy DNA能特异与核蛋白中雄激素受体结合。LNCaP细胞转染ARE decoy DNA后，镜下观察部分细胞出现凋亡形态学的改变，细胞体外生长受到抑制，染色体DNA凝胶电泳可见明显梯形条带。转染48h的凋亡率为22.4%。 结论:实验表明ARE decoy DNA能竞争结合雄激素受体(AR)，阻断AR的作用而诱导LNCaP细胞凋亡，有可能为前列腺肿瘤的治疗提供新的策略。     

13-cis retinoic acid inhibits development and progression of chronic allograft nephropathy

Chronic allograft nephropathy is characterized by chronic inflammation and fibrosis. Because retinoids exhibit anti-proliferative, anti-inflammatory, and anti-fibrotic functions, the effects of low and high doses of 13-cis-retinoic acid (13cRA) were studied in a chronic Fisher344-->Lewis transplantation model. In 13cRA animals, independent of dose (2 or 20 mg/kg body weight/day) and start (0 or 14 days after transplantation) of 13cRA administration, serum creatinine was significantly lower and chronic rejection damage was dramatically reduced, including subendothelial fibrosis of preglomerular vessels and chronic tubulointerstitial damage. The number of infiltrating mononuclear cells and their proliferative activity were significantly diminished. The mRNA expression of chemokines (MCP-1/CCL2, MIP-1alpha/CCL3, IP-10/CXCL10, RANTES/CCL5) and proteins associated with fibrosis (plasminogen activator inhibitor-1, transforming growth factor-beta1, and collagens I and III) were strikingly lower in treated allografts. In vitro, activated peritoneal macrophages of 13cRA-treated rats showed a pronounced decrease in protein secretion of inflammatory cytokines (eg, tumor necrosis factor-alpha, interleukin-6). The suppression of the proinflammatory chemokine RANTES/CCL5 x 13cRA in fibroblasts could be mapped to a promoter module comprising IRF-1 and nuclear factor-kappaB binding elements, but direct binding of retinoid receptors to promoter elements could be excluded. In summary, 13cRA acted as a potent immunosuppressive and anti-fibrotic agent able to prevent and inhibit progression of chronic allograft nephropathy.     

Preantral follicle culture as a novel in vitro assay in reproductive toxicology testing in mammalian oocytes

The most common genetic disorder in humans, trisomy, is caused predominantly by errors in chromosome segregation during oogenesis. Isolated mouse oocytes resuming meiosis and progressing to metaphase II in vitro have recently been used to assess targets, aneugenic potential and sensitivity of oocytes to chemical exposures. In order to extend in vitro maturation tests to earlier stages of oogenesis, an in vitro assay with mouse preantral follicle cultures has been established. It permits the identification of direct and also indirect effects of environmental chemicals on the somatic compartment, the follicle and theca cells, that may lead to disturbances of oocyte growth, maturation and chromosome segregation. Early preantral follicles from prepubertal female mice are cultured in microdroplets for 12 days under strictly controlled conditions. The follicle-enclosed oocytes resume maturation, develop to metaphase II and become in vitro ovulated within 16 h after a physiological ovulatory stimulus with recombinant human gonadotrophins and epidermal growth factor. These oocytes grown and matured in vitro possess normal barrel-shaped spindles with well-aligned chromosomes. Their chromosomes segregate with high fidelity during anaphase I. The model aneugen colchicine induced a meiotic arrest and aneuploidy in these in vitro grown, follicle-enclosed oocytes in a dose-dependent manner, comparable to in vivo tests. Therefore, preantral follicle culture appears to provide an effective and reliable method to assess the influences of environmental mutagens, pharmaceutical agents and potentially endocrine disrupting chemicals on the fidelity of female meiosis.     

Aneuploidy in mouse metaphase II oocytes exposed in vivo and in vitro in preantral follicle culture to nocodazole

Aneuploidy tests are important in evaluating genetic hazards especially when chemical exposures are suspected to affect the fidelity of chromosome segregation in oocytes and embryos. In the current study, a newly established method, mouse preantral follicle culture, was employed to grow oocytes in vitro within follicles. The sensitivity of in vitro grown follicle enclosed oocytes was compared with oocytes maturing in vivo in the ovary. In both the cases, oocytes were exposed to the cytostatic chemical, nocodazole, from the time of hormonally stimulated resumption of meiosis. The in vivo study revealed a significant decrease in the number of ovulated mouse oocytes and an increase in meiosis I-arrested and hyperploid metaphase II oocytes at a single i.p. dose of 70 mg/kg body weight of nocodazole. A significant increase was also observed in the number of meiosis I-arrested and hyperploid mouse oocytes from preantral follicle culture, when they were cultured in the presence of >or=30 nM nocodazole during the final stages of maturation. This concentration is slightly lower than that previously shown to induce nondisjunction in denuded mouse oocytes or in cultured human lymphocytes. The higher sensitivity of the in vitro matured oocytes from preantral follicle culture than that of denuded oocytes may be related to a synergistic adverse influence of nocodazole on the oocyte, on somatic cell integrity and on cell-cell communication, which possibly also affects ovulation in vivo. When expressed in molarity relative to the mouse weight, the effective dose of the acute exposure in vivo is 3-4 orders of magnitude higher than the lowest effective concentration employed continuously in vitro. Reduced bioavailability of nocodazole to the target cells due to its poor water solubility may contribute to this difference. Preantral follicle culture can be helpful in analysing mechanisms in chemically induced aneuploidy in mammalian oogenesis, and in predicting the consequences of chemical exposures in vivo.