Abstract 3133: Identification and functional validation of novel genetically-linked breast cancer targets through pooled gain-of-function screening

Breast cancer is one of the most common cancer types, with greater than 450,000 deaths reported per year worldwide. Through genome wide sequencing efforts, multiple genetic alterations have been identified, including mutations and amplifications in genes such as v-erb-b2 erythroblastic leukemia viral oncogene homolog 2 (ERBB2), GATA binding protein 3 (GATA3), phosphatidylinositol 3-kinase alpha catalytic subunit (PIK3CA) as well as novel genomic rearrangements such as the recently identified MAGI3-AKT3 fusion. Now that breast cancer can be characterized to an unprecedented level, one of the key challenges remaining is to identify and distinguish critical ‘driver’ events responsible for tumor progression, from neutral ‘passenger’ lesions. In order to achieve this, we utilized high resolution aCGH analysis of 50 purified breast cancer samples (made up of Her2+, estrogen receptor positive (ER+) and triple negative tumors with variable responses to SOC regimens), in combination with a Gain-of-Function transformation screen to identify and validate novel breast targets. 158 genomic regions were found to be recurrently amplified, consisting of 759 genes in total. The top 32 focally amplified genes, along with 12 cancer-relevant mutant alleles were prioritized and a library generated utilizing the pTRIPZ-tetracycline regulated inducible lentiviral vector system. These 44 genes were subsequently combined into 16 different target pools (5-13 targets per pool, co-expressing genes that were co-amplified in the same clinical specimen) and evaluated for their ability to transform immortalized breast epithelial MCF10A cells (both wild-type and p53 -/- cells). Through this screening approach, p21-activated kinase 1 (PAK1) was identified, whose kinase activity was required to robustly transform MCF10A cells through regulating multiple signalling pathways including MAPK. Several other putative oncogenes were also identified and will be presented here, including the glycosyltransferse asparagine-linked glycosylation 8 (ALG8). Interestingly, PAK1 and ALG8 are co-amplified in both breast (8%) and ovarian cancers (11%). Our target validation studies have suggested that ALG8 can support PAK1-induced transformation, as dramatic suppression of soft-agar colony growth was seen in co-amplified breast cancer cell lines upon combined siRNA treatment to both targets. Thus, this combined high resolution aCGH profiling and functional screening approach has enabled the successful identification of novel oncogenic targets in breast cancer.

Citation Format: Krishna Vasudevan, Axel Hernandez, Zhongwu Lai, Yonghong Xiao, Nin Guan, Carolyn Hardy, Robert Godin, Christopher Denz, Minwei Ye, Elizabeth Lenkiewicz, Stephanie Savage, Michael T. Barrett, Donna Prunkard, Peter Rabinovitch, Mark Basik, Ewa Przybytkowski, Kevin Webster, Michael Zinda, Emma-Louise Jenkins. Identification and functional validation of novel genetically-linked breast cancer targets through pooled gain-of-function screening. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 3133. doi:10.1158/1538-7445.AM2013-3133

Development of indirect ELISAs for differential serodiagnosis of classical and highly pathogenic porcine reproductive and respiratory syndrome virus

The objective of this study was to develop two indirect enzyme-linked immunosorbent assays (iELISAs) for detection of serum antibodies against classical vaccine strain of porcine reproductive and respiratory syndrome virus (PRRSV) and highly pathogenic PRRSV (HP-PRRSV). To detect the common antibodies against classical and HP-PRRSV, the coating antigen used in the iELISA (designated iELISA-180) was the antigen of Nsp2-180, the 180aa at amino terminal of Nsp2. To detect the different antibodies against classical and HP-PRRSV, the coating antigen in the second iELISA (designated iELISA-D29) was Nsp2-D29, the deleted 29aa in Nsp2 of HP-PRRSV. The antigen concentration and serum dilutions were optimized using a draughtboard titration. The cut-off values of 0.361 at OD(450nm) for the iELISA-180 and 0.27 at OD(450nm) for the iELISA-D29 were determined by testing a panel of 120 classical PRRSV positive and 198 PRRSV negative pig serum samples, which generated the specificity of 97.1% and 96.7%, the sensitivity of 96.9% and 96.3% for iELISA-180 and iELISA-D29, respectively. The agreements between the Western blot and iELISA-180 and iELISA-D29 were 98%, 96.7%, respectively. The developed iELISAs can be used to differentiate serologically HP-PRRSV from the vaccinated or classical PRRSV in clinical serum samples.

Integrative functional genomics identifies RINT1 as a novel GBM oncogene

Large-scale cancer genomics efforts are identifying hundreds of somatic genomic alterations in glioblastoma (GBM). Distinguishing between active driver and neutral passenger alterations requires functional assessment of each gene; therefore, integrating biological weight of evidence with statistical significance for each genomic alteration will enable better prioritization for downstream studies. Here, we demonstrate the feasibility and potential of in vitro functional genomic screens to rapidly and systematically prioritize high-probability candidate genes for in vivo validation. Integration of low-complexity gain- and loss-of-function screens designed on the basis of genomic data identified 6 candidate GBM oncogenes, and RINT1 was validated as a novel GBM oncogene based on its ability to confer tumorigenicity to primary nontransformed murine astrocytes in vivo. Cancer genomics-guided low-complexity genomic screens can quickly provide a functional filter to prioritize high-value targets for further downstream mechanistic and translational studies.

STAR RNA-binding protein Quaking suppresses cancer via stabilization of specific miRNA

Multidimensional cancer genome analysis and validation has defined Quaking (QKI), a member of the signal transduction and activation of RNA (STAR) family of RNA-binding proteins, as a novel glioblastoma multiforme (GBM) tumor suppressor. Here, we establish that p53 directly regulates QKI gene expression, and QKI protein associates with and leads to the stabilization of miR-20a; miR-20a, in turn, regulates TGFβR2 and the TGFβ signaling network. This pathway circuitry is substantiated by in silico epistasis analysis of its components in the human GBM TCGA (The Cancer Genome Atlas Project) collection and by their gain- and loss-of-function interactions in in vitro and in vivo complementation studies. This p53-QKI-miR-20a-TGFβ pathway expands our understanding of the p53 tumor suppression network in cancer and reveals a novel tumor suppression mechanism involving regulation of specific cancer-relevant microRNAs.

microRNA regulatory network inference identifies miR-34a as a novel regulator of TGF-β signaling in glioblastoma

Leveraging The Cancer Genome Atlas (TCGA) multidimensional data in glioblastoma, we inferred the putative regulatory network between microRNA and mRNA using the Context Likelihood of Relatedness modeling algorithm. Interrogation of the network in context of defined molecular subtypes identified 8 microRNAs with a strong discriminatory potential between proneural and mesenchymal subtypes. Integrative in silico analyses, a functional genetic screen, and experimental validation identified miR-34a as a tumor suppressor in proneural subtype glioblastoma. Mechanistically, in addition to its direct regulation of platelet-derived growth factor receptor-alpha (PDGFRA), promoter enrichment analysis of context likelihood of relatedness-inferred mRNA nodes established miR-34a as a novel regulator of a SMAD4 transcriptional network. Clinically, miR-34a expression level is shown to be prognostic, where miR-34a low-expressing glioblastomas exhibited better overall survival. This work illustrates the potential of comprehensive multidimensional cancer genomic data combined with computational and experimental models in enabling mechanistic exploration of relationships among different genetic elements across the genome space in cancer.

SIGNIFICANCE

We illustrate here that network modeling of complex multidimensional cancer genomic data can generate a framework in which to explore the biology of cancers, leading to discovery of new pathogenetic insights as well as potential prognostic biomarkers. Specifically in glioblastoma, within the context of the global network, promoter enrichment analysis of network edges uncovered a novel regulation of TGF-β signaling via a Smad4 transcriptomic network by miR-34a.

Oncogenic Kras maintains pancreatic tumors through regulation of anabolic glucose metabolism

Tumor maintenance relies on continued activity of driver oncogenes, although their rate-limiting role is highly context dependent. Oncogenic Kras mutation is the signature event in pancreatic ductal adenocarcinoma (PDAC), serving a critical role in tumor initiation. Here, an inducible Kras(G12D)-driven PDAC mouse model establishes that advanced PDAC remains strictly dependent on Kras(G12D) expression. Transcriptome and metabolomic analyses indicate that Kras(G12D) serves a vital role in controlling tumor metabolism through stimulation of glucose uptake and channeling of glucose intermediates into the hexosamine biosynthesis and pentose phosphate pathways (PPP). These studies also reveal that oncogenic Kras promotes ribose biogenesis. Unlike canonical models, we demonstrate that Kras(G12D) drives glycolysis intermediates into the nonoxidative PPP, thereby decoupling ribose biogenesis from NADP/NADPH-mediated redox control. Together, this work provides in vivo mechanistic insights into how oncogenic Kras promotes metabolic reprogramming in native tumors and illuminates potential metabolic targets that can be exploited for therapeutic benefit in PDAC.

Telomerase reactivation following telomere dysfunction yields murine prostate tumors with bone metastases

To determine the role of telomere dysfunction and telomerase reactivation in generating pro-oncogenic genomic events and in carcinoma progression, an inducible telomerase reverse transcriptase (mTert) allele was crossed onto a prostate cancer-prone mouse model null for Pten and p53 tumor suppressors. Constitutive telomerase deficiency and associated telomere dysfunction constrained cancer progression. In contrast, telomerase reactivation in the setting of telomere dysfunction alleviated intratumoral DNA-damage signaling and generated aggressive cancers with rearranged genomes and new tumor biological properties (bone metastases). Comparative oncogenomic analysis revealed numerous recurrent amplifications and deletions of relevance to human prostate cancer. Murine tumors show enrichment of the TGF-β/SMAD4 network, and genetic validation studies confirmed the cooperative roles of Pten, p53, and Smad4 deficiencies in prostate cancer progression, including skeletal metastases. Thus, telomerase reactivation in tumor cells experiencing telomere dysfunction enables full malignant progression and provides a mechanism for acquisition of cancer-relevant genomic events endowing new tumor biological capabilities.

Antiviral therapy and outcomes of patients with pneumonia caused by influenza A pandemic (H1N1) virus

BACKGROUND

There is limited data on the clinical outcome of patients with pandemic H1N1 (pH1N1) pneumonia who received oseltamivir treatment, especially when the treatment was administered more than 48 hours after symptom onset.

METHODS

During the pandemic in 2009, a cohort of pH1N1 influenza pneumonia was built in China, and their clinical information was collected systematically, and analyzed with Cox models.

RESULTS

920 adults and 541 children with pneumonia who didn't receive corticosteroids were analyzed. In-hospital mortality was higher in adults who did not receive antiviral therapy (18.2%) than those with who received oseltamivir ≤ 2 days (2.9%), between 2-5 days (4.6%) and >5 days after illness onset (4.9%), p<0.01. A similar trend was observed in pediatric patients. Cox regression showed that at 60 days after symptoms onset, 11 patients (10.8%) who did not receive antivirals died versus 4 (1.8%), 18 (3.3%), and 23 (3.7%) patients whose oseltamivir treatment was started ≤ 2 days, between 2-5 days, and >5 days, respectively. For males patients, aged ≥ 14 years and baseline PaO(2)/FiO(2)<200, oseltamivir administration reduced the mortality risk by 92.1%, 88% and 83.5%, respectively. Higher doses of oseltamivir (>3.8 mg/kg/d) did not improve clinical outcome (mortality, higher dose 2.5% vs standard dose 2.8%, p>0.05).

CONCLUSIONS

Antiviral therapy might reduce mortality of patients with pH1N1 pneumonia, even when initiated more than 48 hours after onset of illness. Greater protective effects might be in males, patients aged 14-60 years, and patients with PaO(2)/FiO(2)<200.

The major aminoglycoside-modifying enzyme AAC(3)-II found in Escherichia coli determines a significant disparity in its resistance to gentamicin and amikacin in China

The aim of this study was to investigate the prevalence of aminoglycoside-modifying enzymes in Escherichia coli in different areas of China and to explore the relationship between pandemic enzyme type and bacterial resistance to antimicrobial agents in China. Gentamicin- or etimicin-resistant clinical isolates of E. coli were collected from different areas of China, and the in vitro antibacterial activity of 11 aminoglycoside agents was determined using standard (Clinical and Laboratory Standards Institute) agar dilution methods. Twelve aminoglycoside-modifying enzyme genes were detected by PCR and confirmed by DNA sequencing. A total of 205 E. coli strains were collected from nine hospitals in seven cities. All strains were highly resistant to gentamicin or etimicin, whereas resistance to tobramycin, netilmicin, and kanamycin was slightly lower. However, less than 15% of isolates were resistant to amikacin and isepamicin. Of the gentamicin-resistant strains, 88.2% and 86.7% were sensitive to isepamicin and amikacin, respectively. Five aminoglycoside-modifying enzyme genes were detected in 191 strains, whereas the remaining 14 strains were negative. The most common gene type was aac(3)-II (162 strains), followed by aac(6')-I (50 strains), ant(3″)-I (28 strains), aph(3')-II (20 strains), and ant(2″)-I (20 strains). Ninety-five strains yielded aac(3)-II only, whereas the others contained two or three genes. The three main gene combinations were aac(6')-I/aac(3)-II (28 strains), aac(3)-II/ant(3″)-I (11 strains), and aac(3)-II/aac(6')-I (10 strains). Regional bacterial resistance and enzyme distribution were roughly similar, although minor differences were found in Guangzhou, Jinan, and Dalian, which were the sources of most of the amikacin- or isepamicin-resistant strains. Chinese clinical isolates of E. coli remain highly resistant to gentamicin and etimicin, but are susceptible to amikacin and isepamicin. The dominant type of aminoglycoside-modifying enzyme, AAC(3)-II, might be the main source of the disparity in E. coli resistance to different aminoglycoside agents.

Selective killing of mixed lineage leukemia cells by a potent small-molecule DOT1L inhibitor

Mislocated enzymatic activity of DOT1L has been proposed as a driver of leukemogenesis in mixed lineage leukemia (MLL). The characterization of EPZ004777, a potent, selective inhibitor of DOT1L is reported. Treatment of MLL cells with the compound selectively inhibits H3K79 methylation and blocks expression of leukemogenic genes. Exposure of leukemic cells to EPZ004777 results in selective killing of those cells bearing the MLL gene translocation, with little effect on non-MLL-translocated cells. Finally, in vivo administration of EPZ004777 leads to extension of survival in a mouse MLL xenograft model. These results provide compelling support for DOT1L inhibition as a basis for targeted therapeutics against MLL.

Proinvasion metastasis drivers in early-stage melanoma are oncogenes

Clinical and genomic evidence suggests that the metastatic potential of a primary tumor may be dictated by prometastatic events that have additional oncogenic capability. To test this "deterministic" hypothesis, we adopted a comparative oncogenomics-guided function-based strategy involving: (1) comparison of global transcriptomes of two genetically engineered mouse models with contrasting metastatic potential, (2) genomic and transcriptomic profiles of human melanoma, (3) functional genetic screen for enhancers of cell invasion, and (4) evidence of expression selection in human melanoma tissues. This integrated effort identified six genes that are potently proinvasive and oncogenic. Furthermore, we show that one such gene, ACP5, confers spontaneous metastasis in vivo, engages a key pathway governing metastasis, and is prognostic in human primary melanomas.

PTEN is a major tumor suppressor in pancreatic ductal adenocarcinoma and regulates an NF-κB-cytokine network

Initiation of pancreatic ductal adenocarcinoma (PDAC) is driven by oncogenic KRAS mutation, and disease progression is associated with frequent loss of tumor suppressors. In this study, human PDAC genome analyses revealed frequent deletion of the PTEN gene as well as loss of expression in primary tumor specimens. A potential role for PTEN as a haploinsufficient tumor suppressor is further supported by mouse genetic studies. The mouse PDAC driven by oncogenic Kras mutation and Pten deficiency also sustains spontaneous extinction of Ink4a expression and shows prometastatic capacity. Unbiased transcriptomic analyses established that combined oncogenic Kras and Pten loss promotes marked NF-κB activation and its cytokine network, with accompanying robust stromal activation and immune cell infiltration with known tumor-promoting properties. Thus, PTEN/phosphoinositide 3-kinase (PI3K) pathway alteration is a common event in PDAC development and functions in part to strongly activate the NF-κB network, which may serve to shape the PDAC tumor microenvironment.

SCF(FBW7) regulates cellular apoptosis by targeting MCL1 for ubiquitylation and destruction

The effective use of targeted therapy is highly dependent upon the identification of responder patient populations. Loss of the Fbw7 tumor suppressor is frequently found in various types of human cancers including breast cancer, colon cancer 1 and T-cell acute lymphoblastic leukemia (T-ALL)2. In line with these genomic data, engineered deletion of Fbw7 in mouse T cells results in T-ALL3–5, validating Fbw7 as a T-ALL tumor suppressor. The precise molecular mechanisms by which Fbw7 exerts anti-tumor activity remain areas of intensive investigation and are thought to relate in part to Fbw7-mediated destruction of key cancer relevant proteins including c-Jun6, c-Myc 7, Cyclin E 8 and Notch-19, all of which possess oncogenic activity and are overexpressed in various human cancers including leukemia. Besides accelerating cell growth 10, overexpression of either c-Jun, c-Myc or Notch-1 can also provoke programmed cell death 11. Thus, considerable uncertainty surrounds how Fbw7-deficient cells evade cell death in the setting of upregulated c-Jun, c-Myc and/or Notch-1. Here we report that SCF^Fbw7 governs cellular apoptosis by targeting the pro-survival Bcl-2 family member, Mcl-1, for ubiquitination and destruction in a GSK3 phosphorylation-dependent manner. Human T-ALL cell lines showed a close relationship between Fbw7 loss and Mcl-1 overexpression. Correspondingly, T-ALL cell lines with defective Fbw7 are particularly sensitive to the multi-kinase inhibitor, sorafenib, but resistant to the Bcl-2 antagonist, ABT-737. On the genetic level, Fbw7 reconstitution or Mcl-1 depletion restores ABT-737 sensitivity, establishing Mcl-1 as a therapeutically relevant bypass survival mechanism for Fbw7-deficient cells to evade apoptosis. Therefore, our work provides novel molecular insight into Fbw7-direct tumor suppression with direct implications for the targeted treatment of Fbw7-deficient T-ALL patients.

[A multi-center, randomized, controlled, double blind and double dummy clinical trial of antofloxacin hydrochloride tablet versus levofloxacin tablet for the treatment of acute bacterial infections]

OBJECTIVE

To evaluate the clinical efficacy and safety of antofloxacin hydrochloride tablet for the treatment of acute bacterial infections.

METHODS

A multi-center randomized control, double blind and double dummy clinical trial was conducted; levofloxacin tablet was closed as controlled drug. The duration of treatment was 7-14 days in both groups.

RESULTS

A total of 719 patients were enrolled in the study, in which 359 patients treated with antofloxacin and 360 patients treated with levofloxacin were included. Three hundred and thirty and 337 patients completed the study and met with all the criteria for per-protocol analysis, respectively. By the end of chemotherapy, the cured rates in per protocol set (PPS) population were 79.7% and 77.4%, the effective rates were 95.2% and 96.7%, and the bacterial clearance were 96.7% and 97.5% for the treating and control group, respectively. The clinical and bacterial efficacy of antofloxacin and levofloxacin was comparable by the analysis of infectious sites. Three hundred and fifty-seven and 356 patients in antofloxacin and levofloxacin groups were evaluated the safety. The drug adverse events occurred both in 10.1%, and drug adverse reactions occurred in 7.8% and 7.9% patients in the two groups. The most common drug adverse reactions were mild gastroenteric symptoms. No QTc prolongation was detected in all the patients. One patient in each group had mild blood glucose increase at the end of therapy, but the glucose returned to normal level without any intervention. No statistic significant difference between the two groups in clinical efficacy and safety was detected (P > 0.05).

CONCLUSIONS

Antofloxacin hydrochloride tablet was effective and safe for the treatment of acute bacterial infections.

Integrative genomic profiling of human prostate cancer

Annotation of prostate cancer genomes provides a foundation for discoveries that can impact disease understanding and treatment. Concordant assessment of DNA copy number, mRNA expression, and focused exon resequencing in 218 prostate cancer tumors identified the nuclear receptor coactivator NCOA2 as an oncogene in approximately 11% of tumors. Additionally, the androgen-driven TMPRSS2-ERG fusion was associated with a previously unrecognized, prostate-specific deletion at chromosome 3p14 that implicates FOXP1, RYBP, and SHQ1 as potential cooperative tumor suppressors. DNA copy-number data from primary tumors revealed that copy-number alterations robustly define clusters of low- and high-risk disease beyond that achieved by Gleason score. The genomic and clinical outcome data from these patients are now made available as a public resource.

[Impact of misuse of antimicrobial therapies on inpatient costs]

OBJECTIVE

To evaluate the impact of inappropriate antibiotic use on inpatients' cost during hospitalization.

METHODS

1 000 cases with antibiotic treatment were extracted from 10 hospitals of 5 provinces in China in 2005. We created multivariate linear regression model for hospital cost and Logistic regression model for evaluation of rationality in antibiotic use.

RESULTS

We collected 946 valid cases. Rate of inappropriate antibiotic use was 58.4%. Costs of inpatients with inappropriate antibiotic use was 1.55 times of the ones with appropriate use (P<0.001). Risk factors included antibiotic prophylaxis (OR=2.929), medication for surgery (OR=2.44), long hospital stay (OR=1.021 for every prolonged day) and regional factors. Protection factor was in tertiary hospital (OR=0.510).

CONCLUSION

Inappropriate antibiotic use could add 55% unnecessary cost on inpatients. Efforts to control misuse of antibiotics such as regulating antibiotic prophylaxis and medication for surgery, and decreasing length of stay should be pursued.

Integrative genome comparison of primary and metastatic melanomas

A cardinal feature of malignant melanoma is its metastatic propensity. An incomplete view of the genetic events driving metastatic progression has been a major barrier to rational development of effective therapeutics and prognostic diagnostics for melanoma patients. In this study, we conducted global genomic characterization of primary and metastatic melanomas to examine the genomic landscape associated with metastatic progression. In addition to uncovering three genomic subclasses of metastastic melanomas, we delineated 39 focal and recurrent regions of amplification and deletions, many of which encompassed resident genes that have not been implicated in cancer or metastasis. To identify progression-associated metastasis gene candidates, we applied a statistical approach, Integrative Genome Comparison (IGC), to define 32 genomic regions of interest that were significantly altered in metastatic relative to primary melanomas, encompassing 30 resident genes with statistically significant expression deregulation. Functional assays on a subset of these candidates, including MET, ASPM, AKAP9, IMP3, PRKCA, RPA3, and SCAP2, validated their pro-invasion activities in human melanoma cells. Validity of the IGC approach was further reinforced by tissue microarray analysis of Survivin showing significant increased protein expression in thick versus thin primary cutaneous melanomas, and a progression correlation with lymph node metastases. Together, these functional validation results and correlative analysis of human tissues support the thesis that integrated genomic and pathological analyses of staged melanomas provide a productive entry point for discovery of melanoma metastases genes.

PLAGL2 regulates Wnt signaling to impede differentiation in neural stem cells and gliomas

A hallmark feature of glioblastoma is its strong self-renewal potential and immature differentiation state, which contributes to its plasticity and therapeutic resistance. Here, integrated genomic and biological analyses identified PLAGL2 as a potent protooncogene targeted for amplification/gain in malignant gliomas. Enhanced PLAGL2 expression strongly suppresses neural stem cell (NSC) and glioma-initiating cell differentiation while promoting their self-renewal capacity upon differentiation induction. Transcriptome analysis revealed that these differentiation-suppressive activities are attributable in part to PLAGL2 modulation of Wnt/beta-catenin signaling. Inhibition of Wnt signaling partially restores PLAGL2-expressing NSC differentiation capacity. The identification of PLAGL2 as a glioma oncogene highlights the importance of a growing class of cancer genes functioning to impart stem cell-like characteristics in malignant cells.

Intervention study of the association of antibiotic utilization measures with control of extended-spectrum beta-lactamase (ESBL)-producing bacteria

We investigated the effects of replacing third-/fourth-generation cephalosporins with piperacillin-tazobactam on the rate of acquisition of extended spectrum beta-lactamase-producing Klebsiella pneumoniae and Escherichia coli by patients hospitalized in a Department of Respiratory Medicine. This 9-month, prospective, non-controlled, intervention study comprised two phases: a 3-month pre-intervention phase (Phase I) and a 6-month intervention phase (Phase II), during which the use of third-/forth-generation cephalosporins was restricted and replaced by piperacillin-tazobactam. Rectal swabs were obtained within 24 h after admission (baseline screening), weekly, and 48 h before discharge during Phase I and the last 3 months of Phase II (Phase IIb). Swabs were tested for E. coli and K. pneumoniae, and extended spectrum beta-lactamase production was detected with the double disc test. Use of third/fourth-generation cephalosporins decreased by 63.0% and 100%, respectively; while the use of piperacillin-tazobactam increased by 28-fold. The rate of acquisition of extended spectrum beta-lactamase-producing E. coli and K. pneumoniae together in rectal swab specimens decreased in Phase IIb as compared with Phase I (19.5% vs 29.5%). Few rectal swab specimens were positive for extended spectrum beta-lactamases-producing K. pneumoniae, and no substantial decrease in the rate of its acquisition was observed.

GOLPH3 modulates mTOR signalling and rapamycin sensitivity in cancer

Genome-wide copy number analyses of human cancers identified a frequent 5p13 amplification in several solid tumour types, including lung (56%), ovarian (38%), breast (32%), prostate (37%) and melanoma (32%). Here, using integrative analysis of a genomic profile of the region, we identify a Golgi protein, GOLPH3, as a candidate targeted for amplification. Gain- and loss-of-function studies in vitro and in vivo validated GOLPH3 as a potent oncogene. Physically, GOLPH3 localizes to the trans-Golgi network and interacts with components of the retromer complex, which in yeast has been linked to target of rapamycin (TOR) signalling. Mechanistically, GOLPH3 regulates cell size, enhances growth-factor-induced mTOR (also known as FRAP1) signalling in human cancer cells, and alters the response to an mTOR inhibitor in vivo. Thus, genomic and genetic, biological, functional and biochemical data in yeast and humans establishes GOLPH3 as a new oncogene that is commonly targeted for amplification in human cancer, and is capable of modulating the response to rapamycin, a cancer drug in clinical use.

[Bacterial composition and resistance from urinary tract infections in females]

OBJECTIVE

To determine the bacterial composition and antibacterial resistance in female urinary tract infections (UTI) in China.

METHODS

The disc diffusion test, minimum inhibition concentration (MIC), test or E-test was used to detect the antimicrobial susceptibility in 86 tertiary hospitals in China from June 1, 2006 to May 31, 2007. WHONET 5.4 was applied for data analysis.

RESULTS

A total of 6071 pathogenic germs were collected from urine cultures of UTI female patients in the surveillance period, which included 5958 bacterial isolates. Escherichia coli 3529 strains (59.23%), Enterococcus spp 938 strains (15.74%) and Klebsiella pneumoniae 394 strains (6. 61%) were the most common pathogens. Escherichia coli and Klebsiella pneumoniae had 35.7% and 34.0% extended spectrum beta-lactamases (ESBL) positive rates, and their resistant rates to quinolones were about 70% and 40%, respectively. Enterococcus faecium was much more resistant to almost all the antibiotics than Enterococcus faecalis. 0.9% Escherichia faecalis and 3. 8% Escherichia faecium were resistant to vancomycin, whereas 2.7% and 4.8% were resistant to teicoplanin. Staphylococcus epdermidis was more common in UTI than Staphylococcus aureus, 79.1% and 75.0% of the isolates being methicillin-ressitant Staphylococcus epdermidis (MRSE) or methicillin-ressitant Staphylococcus aureus (MRSA), respectively. No vancomycin intermediate or resistant staphylococcus was detected, but 4.9% teicoplanin intermediate rate was found in Staphylococcus epdermidis. The resistant rates to quinolones increased with the patient age.

CONCLUSIONS

Bacterial resistance in UTI in Chinese females is a severe problem, which could be resulted from antimicrobial irrational use. In the selection of antimicrobial agents in the treatment of UTI, doctors should refer to the results of bacterial resistant surveillance.

Genomic alterations link Rho family of GTPases to the highly invasive phenotype of pancreas cancer

Pancreas ductal adenocarcinoma (PDAC) is a highly lethal cancer that typically presents as advanced, unresectable disease. This invasive tendency, coupled with intrinsic resistance to standard therapies and genome instability, are major contributors to poor long-term survival. The genetic elements governing the invasive propensity of PDAC have not been well elucidated. Here, in the course of validating resident genes in highly recurrent and focal amplifications in PDAC, we have identified Rio Kinase 3 (RIOK3) as an amplified gene that alters cytoskeletal architecture as well as promotes pancreatic ductal cell migration and invasion. We determined that RIOK3 promotes its invasive activities through activation of the small G protein, Rac. This genomic and functional link to Rac signaling prompted a genome wide survey of other components of the Rho family network, revealing p21 Activated Kinase 4 (PAK4) as another amplified gene in PDAC tumors and cell lines. Like RIOK3, PAK4 promotes pancreas ductal cell motility and invasion. Together, the genomic and functional profiles establish the Rho family GTP-binding proteins as integral to the hallmark invasive nature of this lethal disease.

Pharmacokinetics/pharmacodynamics of antofloxacin hydrochloride in a neutropenic murine thigh model of Staphylococcus aureus infection

AIM

Antofloxacin hydrochloride is a new fluoroquinolone antibiotic with broad-spectrum in vitro activity. Using the neutropenic murine thigh infection model, we defined the pharmacodynamic profile and property of antofloxacin hydrochloride against Staphylococcus aureus.

METHODS

Single-dose pharmacokinetic studies of antofloxacin hydrochloride were carried out in thigh infected mice. Therapy was initiated at 2 h postinoculation with 5-640 mg/kg per d fractionated for different dosing regimens. The thighs were removed for bacterial measurement after 24 h of therapy, the best pharmacokinetic/ pharmacodynamic (PK/PD) index correlated with the efficacy was determined by nonlinear regression analysis. A sigmoid E(max) dose-response model was used to estimate the daily dose and AUC(24 h)/MIC (minimal inhibitory concentration) required to achieve a static effect.

RESULTS

The PK was linear with similar elimination half-life over the dose range studied. The AUC(24 h)/MIC ratio was the PK/PD parameter that best correlated with efficacy (R(2)=92.3%, 90.8% for the two organisms, compared with C(max)/MIC and T>MIC [%], respectively). The 24 h static dose ranged from 34.3 to 153.7 mg/kg per d for all S aureus strains, the total AUC(24 h)/MIC ratio to achieve bacteriostatic effect varied from 31.7 to 122.5 (mean, 65.7+/-30.6).

CONCLUSION

Antofloxacin hydrochloride showed powerful antibacterial activity against the S aureus isolates used in our neutropenic infected mice model. Our data suggested that the AUC/MIC ratio appeared to be most closely linked to the bacterial outcome (R(2)>90%), and a total AUC(24 h)/MIC ratio of 65.7 appears to be the target value to achieve a net bactericidal activity against S aureus, similar to the results of other fluoroquinolones.

Pharmacokinetics of antofloxacin hydrochloride, a new fluoroquinolone antibiotic, after single oral dose administration in Chinese healthy male volunteers

Antofloxacin hydrochloride is a newly developed fluoroquinolone antibacterial in China, which has comparable in vitro and animal pharmacological and toxicological properties to levofloxacin and is worthy of further clinical trial. Human tolerance of single escalating doses from 50 to 500 mg was shown to be safe. The purpose of the present study was to evaluate the pharmacokinetic characteristics of a single oral dose of antofloxacin hydrochloride in Chinese healthy male volunteers. Twelve subjects were randomized for administration of a single dose of 300, 400 and 500 mg antofloxacin hydrochloride in a 3-way crossover design. High pressure liquid chromatography (HPLC) was used to assay the serum and urine concentrations of antofloxacin in samples collected over a period of 72 h following drug administration. All three dosages were well tolerated. Antofloxacin hydrochloride demonstrated linear pharmacokinetic characteristics with mean pharmacokinetic values varying from 0.09 to 0.10 l/h/kg for CL/F and from 2.75-3.00 l/kg for V/F. The t(1/2beta) was around 20 h and the mean fraction of dose excreted in urine varied from 0.40 to 0.46. Based on these data, 300 mg of antofloxacin hydrochloride administered once daily was selected for further investigation in a multiple dose administration study.

Bacterial resistance surveillance in China: a report from Mohnarin 2004-2005

The aim of this study was to establish a nationwide antimicrobial resistant surveillance network and obtain information on bacterial resistance in China. A total of 4075 clinical bacterial isolates were collected from 17 hospitals in 15 cities throughout China. Antibacterial minimal inhibitory concentrations (MICs) were determined by the standard agar dilution method recommended by Clinical and Laboratory Standards Institute. The results of the MICs revealed the following bacterial resistance characteristics. Oxacillin resistance was shown by 62.9% of Staphylococcus aureus and 82.89% of Staphylococcus epidermidis strains. Penicillin non-sensitivity was show by 40.7% of the Streptococcus pneumoniae strains, which included 10.5% penicillin-resistant strains and 30.2% penicillin-intermediate strains. Five strains of Enterococci were vancomycin-intermediate, but all Enterococci strains were sensitive to teicoplanin. All Staphylococci were susceptible to glycopeptides. A high resistance to macrolides was a predominant characteristic of the Gram-positive cocci. Enterobacteriaceae strains were clearly resistant to the third generation cephalosporins, with the exception of ceftazidime, and the resistance rates ranged from 20 to 70%. About 65% of the Escherichia coli strains were resistant to fluoroquinolones. Carbapenems remained highly active against all the target bacteria. Latamoxef, piperacillin/tazobactam, cefoperazone/sulbactam and cefepime were all active against Enterobacteriaceae, which showed resistant rates of less than 10%. Imipenem resistance was found in 10.6% of Pseudomonas aeruginosa and 10.4% of Acinetobacter baumannii strains, most of which were multidrug resistant isolates. Combinations of beta-lactam/beta-lactamase inhibitor and fluoroquinolones also had potent antibacterial activity against non-fermenters. Amikacin was active against Enterobacteriaceae and P. aeruginosa. In conclusion, methicillin-resistant Staphylococci, penicillin-insensitive S. pneumoniae, macrolides-resistant Gram-positive cocci, cephalosporin-resistant Enterobacteriaceae, multidrug-resistant nonfermenters and fluoroquinolone-resistant E. coli were revealed to be the most serious problems in terms of bacteria resistance in China. No glycopeptides-resistant Staphylococcus strains were isolated, and the appearance of glycopeptides-resistant Enterococci was seldom.

Feedback circuit among INK4 tumor suppressors constrains human glioblastoma development

We have developed a nonheuristic genome topography scan (GTS) algorithm to characterize the patterns of genomic alterations in human glioblastoma (GBM), identifying frequent p18(INK4C) and p16(INK4A) codeletion. Functional reconstitution of p18(INK4C) in GBM cells null for both p16(INK4A) and p18(INK4C) resulted in impaired cell-cycle progression and tumorigenic potential. Conversely, RNAi-mediated depletion of p18(INK4C) in p16(INK4A)-deficient primary astrocytes or established GBM cells enhanced tumorigenicity in vitro and in vivo. Furthermore, acute suppression of p16(INK4A) in primary astrocytes induced a concomitant increase in p18(INK4C). Together, these findings uncover a feedback regulatory circuit in the astrocytic lineage and demonstrate a bona fide tumor suppressor role for p18(INK4C) in human GBM wherein it functions cooperatively with other INK4 family members to constrain inappropriate proliferation.

Design and evaluation of sifuvirtide, a novel HIV-1 fusion inhibitor

Enfuvirtide (T20) is the first and only HIV-1 fusion inhibitor approved for clinical use, but it can easily induce drug resistance limiting its practical application. A novel anti-HIV peptide, termed sifuvirtide, was designed based on the three-dimensional structure of the HIV-1 gp41 fusogenic core conformation. Here we report its in vitro anti-HIV potency, its mechanism of action, as well as the results from Phase Ia clinical studies. We demonstrated that sifuvirtide inhibited HIV-1-mediated cell-cell fusion in a dose-dependent manner and exhibited high potency against infections by a wide range of primary and laboratory-adapted HIV-1 isolates from multiple genotypes with R5 or X4 phenotypes. Notably, sifuvirtide was also highly effective against T20-resistant strains. Unlike T20, sifuvirtide could efficiently block six-helix bundle formation in a dominant negative fashion. These results suggest that sifuvirtide has a different mechanism of action from that of T20. Phase Ia clinical studies of sifuvirtide (FS0101) in 60 healthy individuals demonstrated good safety, tolerability, and pharmacokinetic profiles. A single dose regimen (5, 10, 20, 30, and 40 mg) by subcutaneous injection once daily at abdominal sites was well tolerated without serious adverse events. Pharmacokinetic studies of single and multiple administration of sifuvirtide showed that its decay half-lives were 20.0 +/- 8.6 h and 26.0 +/- 7.9 h, respectively. In summary, sifuvirtide has potential to become an ideal fusion inhibitor for treatment of HIV/AIDS patients, including those with HIV-1 strains resistant to T20.

Common and distinct genomic events in sporadic colorectal cancer and diverse cancer types

Colorectal cancer (CRC) is a major cause of cancer morbidity and mortality, and elucidation of its underlying genetics has advanced diagnostic screening, early detection, and treatment. Because CRC genomes are characterized by numerous non-random chromosomal structural alterations, we sought to delimit regions of recurrent amplifications and deletions in a collection of 42 primary specimens and 37 tumor cell lines derived from chromosomal instability neoplasia and microsatellite instability neoplasia CRC subtypes and to compare the pattern of genomic aberrations in CRC with those in other cancers. Application of oligomer-based array-comparative genome hybridization and custom analytic tools identified 50 minimal common regions (MCRs) of copy number alterations, 28 amplifications, and 22 deletions. Fifteen were highly recurrent and focal (<12 genes) MCRs, five of them harboring known CRC genes including EGFR and MYC with the remaining 10 containing a total of 65 resident genes with established links to cancer. Furthermore, comparisons of these delimited genomic profiles revealed that 22 of the 50 CRC MCRs are also present in lung cancer, glioblastoma, and/or multiple myeloma. Among 22 shared MCRs, nine do not contain genes previously shown genetically altered in cancer, whereas the remaining 13 harbor 35 known cancer genes, of which only 14 have been linked to CRC pathogenesis. Together, these observations point to the existence of many yet-to-be discovered cancer genes driving CRC development, as well as other human cancers, and show the utility of high-resolution copy number analysis in the identification of genetic events common and specific to the development of various tumor types.

The first molecular analysis of clinical isolates of VanA-type vancomycin-resistant Enterococcus faecium strains in Mainland China

AIMS

The aim of this study was to examine two VanA-type vancomycin-resistant Enterococcus faecium (VRE) strains that had been isolated from patients resident in mainland China. This is the first molecular analysis of clinical VRE strains being isolated in mainland China.

METHODS AND RESULTS

Two VanA-type VRE isolates were isolated from in-patients at hospitals located in the Chinese cities Beijing and Dalian and were designated C264 and I125. The plasmids pC264V (40 kbp) and pI125V (370 kbp) that were isolated from C264 and I125, respectively, carried a Tn1546-like element encoding VanA resistance. The vancomycin-resistant plasmids pC264V and pI125V were transferred by filter mating at frequencies of 10(-7) and 10(-4) respectively. Sequence analysis of pC264V revealed that two IS1216V sequences and an IS1542 sequence were present within the Tn1546-like element. pI125V had two IS1216V insertions in the Tn1546-like element.

CONCLUSIONS

The two VanA-type vancomycin-resistant E. faecium (VRE) strains C264 and I125 were isolated from in-patients in Chinese hospitals. The vancomycin-resistant conjugative plasmids pC264V and pI125V plasmids isolated from these strains carried the Tn1546-like element. The Tn1546-like element was found to contain the insertion sequences IS1216V and IS1542.

SIGNIFICANCE AND IMPACT OF THE STUDY

This is the first molecular analysis of VanA-type VRE strains from patients resident in mainland China.

FoxOs are lineage-restricted redundant tumor suppressors and regulate endothelial cell homeostasis

Activated phosphoinositide 3-kinase (PI3K)-AKT signaling appears to be an obligate event in the development of cancer. The highly related members of the mammalian FoxO transcription factor family, FoxO1, FoxO3, and FoxO4, represent one of several effector arms of PI3K-AKT signaling, prompting genetic analysis of the role of FoxOs in the neoplastic phenotypes linked to PI3K-AKT activation. While germline or somatic deletion of up to five FoxO alleles produced remarkably modest neoplastic phenotypes, broad somatic deletion of all FoxOs engendered a progressive cancer-prone condition characterized by thymic lymphomas and hemangiomas, demonstrating that the mammalian FoxOs are indeed bona fide tumor suppressors. Transcriptome and promoter analyses of differentially affected endothelium identified direct FoxO targets and revealed that FoxO regulation of these targets in vivo is highly context-specific, even in the same cell type. Functional studies validated Sprouty2 and PBX1, among others, as FoxO-regulated mediators of endothelial cell morphogenesis and vascular homeostasis.

[Study of the expression of exogenous augmenter of liver regeneration recombinant plasmid in liver tissue of rat]

OBJECTIVE

To observe the expression of exogenous ALR recombinant plasmid in liver tissue of rats suffered from immune hepatic fibrosis.

METHODS

Immune hepatic fibrosis model of rats were made by using porcine serum, which were treated by pcDNA3-ALR recombinant plasmid. The expression of ALR proteins in liver tissue were detected by immunohistochemistry staining and Western blotting and the expression of ALR mRNA were detected by RT-PCR.

RESULTS

ALR were expressed in liver tissue in all group rats. ALR expressions were lower in normal control groups , and were higher in ALR treat groups. The results of image analysis by immunohistochemistry were (0.109 +/- 0.01), (0.159 +/- 0.02) and (0.198 +/- 0.04) in normal groups, model groups and ALR groups respectively. There were significant differences between model and normal groups ( P < 0.01) as well as ALR groups and model groups (P < 0.01). The results of Western blotting were similar to immunohistochemistry. The specific 550bp gene fragments that were amplified by RT-PCR with a couple of especial primers were found in ALR group but not in normal and model groups, which was coincident with fragments amplified by PCR with ALR recombinant plasmid extracted directly from competent E. coli DH5.

CONCLUSION

The expression of ALR was relatively low abundance in normal rat liver tissue, and increased markedly in immune injured rat liver tissue. The expression of the pcDNA3-ALR recombinant plasmid can be found in rat liver tissue suffered from immune hepatic fibrosis. The reinforcements of expression of ALR protein in liver tissue of pcDNA3-ALR recombinant plasmid treatment group was resulted from the overlap of endogenous and exogenous ALR expression.

[Study on drug resistance and molecular epidemiology of Streptococcus pneumoniae isolated in Chongqing]

OBJECTIVE

To investigate the prevalence and drug resistance of Streptococcus (S.) pneumoniae in patients infected in communities and molecular epidemiology with BOX-polymerase chain reaction (PCR) in Chongqing areas.

METHODS

A total of 680 clinical specimens from sputum and throat/nasal swabs were collected from patients seen from September 2000 to March 2001. Antibiotic susceptibility was determined by agar dilution test. BOX-PCR was used for molecular typing of S. pneumoniae.

RESULTS

A total of 39 isolates of S. pneumoniae were collected with the isolation rate of 5.7%. Of the 34 S. pneumoniae strains, two showed low-level resistance to penicillin (MIC 0.125 mg/L), one to levofloxacin, but many to macrolide and clindamycin (nearly 70%). All the strains were susceptible to beta-lactams and vancomycin. BOX-PCR typing demonstrated a high discriminatory potential and easy to be accurately analysed. 35 S. pneumoniae strains (include ATCC49619) were divided into 25 distinct types, representing 29 subtypes with A (n = 3) as the predominant type. 2 penicillin-resistant strains were shown to be different types.

CONCLUSION

Penicillin resistant rate of S. pneumoniae was low in Chongqing, but macrolide and clindamycin resistant strains were common while BOX-PCR typing was a suitable technique to type S. pneumoniae. No dominant antibiotic resistant strains were found in Chongqing.

[Comparison of pharmacokinetics/pharmacodynamics of cefdinir, cefpodoxime proxetil and cefaclor against common bacteria of community acquired infections]

OBJECTIVE

To compare the pharmacokinetics/pharmacodynamics property of cefdinir, cefpodoxime proxetil and cefaclor against common bacteria of community acquired infections and evaluate the recommended regimens.

METHODS

The antibacterial activities of 3 agents against 238 clinical isolates were determined by standard agar dilution test and the pharmacokinetics of these antibiotics in male healthy volunteers were conducted in Latin-square manner. The time over MIC (T > MIC) of serum antibiotic concentrations were calculated with pharmacokinetic equation and MIC.

RESULTS

The value of MIC90 s cefdinir against these bacterial strains except penicillin non-sensitive pneumococci were 0.031-1 mg/L. Cefpodoxime held similar antibacterial activity with cefdinir, but was less potent against staphylococci. Cefaclor had much higher MIC values than other two drugs. After oral administration of 250 mg cefaclor, the drug concentration quickly reached peak concentration of 4.95 mg/L +/- 2.41 mg/L and the eliminative half time was 0.69 h +/- 0.6 h; the Tmax, Cmax and T1/2beta of cefdinir and cefpodoxime after oral administration of 100 mg were 2.5 h +/- 0.48 h, 0.81 mg/L +/- 0.19 mg/L, 1.73 h +/- 0.3 h and 2.38 h +/- 0.43 h, 1.12 mg/L +/- 0.28 mg/L, 1.92 h +/- 0.55 h, respectively. T > MIC of cefdinir in thrice daily administration were longer than 40% of medication interval against most of the tested isolates; no T > MIC period was found in cefpodoxime against staphylococci and the T > MICs of cefaclor after 250 mg oral administration were shorter than expected values against most bacteria.

CONCLUSION

With powerful antibacterial activity, the T > MICs of cefdinir after 100 mg oral administration can meet with the clinical requirement in most infections; PK/PD value of cefpodoxime proxetil against staphylococci is lower than expectancy and 250 mg cefaclor 3 times daily is not enough to the treatment of common community acquired infections, the regimens of cefpodoxime proxetil and cefclor should be furtherly optimized.

[A study on the clinical and pathological efficacy of lamivudine in the treatment of chronic hepatitis B]

OBJECTIVE

To investigate clinical effect, liver pathohistological changes (including pathology, HBV markers in liver tissue) in patients with chronic hepatitis B.

METHODS

70 patients of chronic hepatitis B were administered 100 mg Lamivudine orally daily for 1 year. The serum HBV-DNA, HBeAg/anti-HBe, hepatic chemistry and the hepatic fibrosis markers were studied. The needle biopsy of liver were performed in 35 patients before and after treatment and Knodell pathological score were done, HBsAg, HBcAg, alpha-SMA in liver tissue were examined by immunohistochemistry method.

RESULTS

After 1 year treatment the full response rate, partial response rate and no response rate were 23.72%, 69.49% and 6.78%, the patients in whom HBeAg seroconversion had higher base-line Alanine aminotransferase levels than the patients without seroconversion. Activity index of hepatic histology in 41.18% patients had a significant decrease. Histological assessment revealed that necrosis in portal area, pylenphlebitis and fibrosis were obviously alleviated. The liver immunohistochemistry examination showed HBcAg and alpha-SMA in liver decreased significantly in the patients with HBeAg seroconversion, no obvious alteration was observed in HBsAg expression. Lamivudine seems an effective compound with high safety and low side effect.

CONCLUSION

These results suggested that lamivudine (100mg/d) could suppress HBV-DNA replication, promote ALT normalization, accelerate HBeAg/anti-HBe seroconversion, improve the liver pathological changes, slow down the development of liver fibrosis

Mechanism of action of Tripterygium Wilfordii polyglycoside on experimental endometriosis

PURPOSE OF INVESTIGATION

This study was designed to examine the therapeutic effectiveness and mechanism of action of Tripterygium Wilfordii polyglycoside (TWP) in the treatment of endometriosis.

METHODS

An experimental endometriosis model was developed using New Zealand White rabbits where endometrial tissue was autotransplanted into the peritoneum. Six weeks after transplantation, a total of 22 rabbits were randomly placed into two groups: Group I (n=17) was treated with TWP (10 mg/kg/day) and Group 2 (n=5) served as the water-fed control for three successive months. The volume of endometrial implants was measured before and after administration of TWP and water. Immune and endocrine systems were investigated in the normal phase, six weeks after induction of endometriosis, and three months after TWP treatment and water administration.

RESULTS

After treatment with TWP, the average volume of endometrial implants significantly decreased (p < 0.0001), and the antiendometrial antibody (EmAb) level decreased (p < 0.05) to near normal levels, but it did not decrease in the untreated controls. Serum FSH and LH levels also decreased after TWP treatment. Furthermore, electron microscopic examination of the pituitary ultrastructure revealed morphological changes in gonadotropic cells (G-cell) after treatment with TWP, and changes gradually disappeared four weeks after withdrawal of TWP.

CONCLUSION

This study indicates that TWP has both hormonal and immune system action that is effective as a medical treatment for experimental endometriosis by modulating both reproductive endocrine functions and immunosuppression that results in remission of the disease.

[An AFLP marker related to fibrogenesis in upland cotton (Gossypium hirsuturm L.)]

By using AFLP technique polymorphism analysis was performed between a fuzzlesslintless mutant line and its isogenic wild-type line, Xuzhou 142. Out of 6,360 bands produced by 64 pairs primers, a fragment, named as CF1, appearing stably in wild-type line, Xuzhou 142. This polymorphism was further verified using several normal fiber varieties and F2, F3 populations from the cross of fuzzless-lintless mutant line with a high-lint-percentage variety Yumian No. 1. The cosegregation of CF1 and fibrogenesis was proved, which suggested that CF1 can be used as a molecular marker for cotton fibrogenesis. The CF1 segment was cloned into PUCm-T Vector and then sequenced. The putative amino acid sequences, is an analogue to phenol hydroxylase alpha subunit, outer surface protein C, NADH dehydrogenase subunit 1, NADH-ubiquinone oxidoreductase, 2-oxoacid ferredoxin oxidoreduct and hypothetical 14.5kD protein.

Usefulness of PCR in situ hybridization as a technique for morphological detection of human papillomavirus in uterine cervical neoplasia

This study was designed in order to devise fitting conditions in polymerase chain reaction (PCR)-in situ hybridization (ISH) for observing human papillomavirus (HPV) infection morphologically in uterine cervical neoplasias and to compare the detection rates of HPV by PCR-ISH and solution phase PCR (S-PCR) as well as fluorescence ISH (FISH). Tissues were obtained from 23 patients with cervical intraepithelial neoplasia 3, who visited our hospital between 1994 and 1997. To detect HPV-16, a HPVpF forward primer and a HPVp 16 reverse primer were used. Compared with the traditional methods, the PCR-ISH technique performed in this study was contrived as follows. To prevent detachment, the specimens were attached to silane-coated slides at 90 degrees C and successively left at room temperature for 36 hours. In proteopepsis, pepsin was used. PCR products were fixed with 4% paraformaldehyde. PCR-ISH, S-PCR, and FISH showed HPV-16 positivity in 52.2%, 56.5% and 21.7%, respectively. The positive rate of HPV-16 detected by PCR-ISH as well as S-PCR was significantly higher than that by FISH (p<0.01, respectively). There was no significant difference between the positive rates of HPV-16 detected by PCR-ISH and S-PCR. HPV-16 was detected by S-PCR in all 12 specimens in which HPV-16 expression was judged as positive using PCR-ISH. Similarly, HPV-16 was found by PCR-ISH in all five specimens in which HPV-16 expression was regarded as positive using FISH. While the FISH technique detected HPV-16 signals only in the superficial and middle layers of squamous cells, the PCR-ISH technique demonstrated them in all the layers including the parabasal and basal layers. The PCR-ISH technique contrived in this study has a high sensitivity to HPV-16 equal to that of S-PCR. The difference in detection rate and distribution of HPV DNA between PCR-ISH and FISH might suggest that HPV does not infect the superficial layer but rather the parabasal layer.

Primary non-Hodgkin's lymphoma of the uterine cervix

We present a patient with primary malignant lymphoma of the uterine cervix, which is extremely rare. She had a complete remission with a combination of chemotherapy and radiotherapy. Measurement of the serum soluble interleukin-2 receptor level was a useful index of the effectiveness of treatment.

[Action of fengsuidan granules on experimental anti-oral ulcer]

OBJECTIVE

To explore the anti-oral ulcer action, anti-inflammatory and analgesic effect of Fengsuidan Granules(FSDG).

METHODS

FSDG(0.5, 5.0, 10.0 g.kg-1) were administered to experimental animals. The oral ulcer in experimental animals was effected by means of white staphylococcus (sc) and carbolic acid (buming).

RESULTS

Such as acetic acid body turning, hot-plate, auricle inflammation by dimethylbenzene and foot swelling by egg white were used.

CONCLUSION

Following certain regularities of dose-effect relationship, FSDG has anti-oral ulcer effect, helps reduce and heal the ulcer and works efficaciously in analgesic and anti-inflammatory cases.

Central nervous system sodium channels are significantly suppressed at clinical concentrations of volatile anesthetics

BACKGROUND

Although voltage-dependent sodium channels have been proposed as possible molecular sites of anesthetic action, they generally are considered too insensitive to be likely molecular targets. However, most previous molecular studies have used peripheral sodium channels as models. To examine the interactions of volatile anesthetics with mammalian central nervous system voltage-gated sodium channels, rat brain IIA sodium channels were expressed in a stably transfected Chinese hamster ovary cell line, and their modification by volatile anesthetics was examined.

METHODS

Sodium currents were measured using whole cell patch clamp recordings. Test solutions were equilibrated with the test anesthetics and perfused externally on the cells. Anesthetic concentrations in the perfusion solution were determined by gas chromatography.

RESULTS

All anesthetics significantly suppressed sodium currents at clinical concentrations. This suppression occurred through at least two mechanisms: (1) a potential-independent suppression of resting or open sodium channels, and (2) a hyperpolarizing shift in the voltage-dependence of channel inactivation resulting in a potential-dependent suppression of sodium currents. The voltage-dependent interaction results in IC50 values for anesthetic suppression of sodium channels that are close to clinical concentrations at potentials near the resting membrane potential.

Voltage- and frequency-dependent pentobarbital suppression of brain and muscle sodium channels expressed in a mammalian cell line

The voltage- and frequency-dependent interactions of pentobarbital with voltage-gated sodium channels were examined in whole-cell patch-clamp recordings. Using rat brain IIA and rat muscle rSkM1 sodium channels expressed in stably transfected Chinese hamster ovary cell lines, it was found that pentobarbital reduced peak inward sodium currents with IC50 values of 1.2 mM (brain) and 1.0 mM (muscle). Analysis of steady state channel availability curves revealed two distinct effects of pentobarbital on both channel isoforms, i.e., a voltage-independent current reduction and an additional hyperpolarizing shift in the voltage dependence of channel availability. The latter effect leads to a voltage dependence of pentobarbital potency. Pentobarbital was also found to slow channel recovery after depolarization, yielding an additional use-dependent component of current suppression. Use-dependent block was enhanced by higher stimulation frequencies, longer pulse durations, and more depolarized holding and pulse potentials. All effects were identical for both channels. These findings can be explained in terms of the modulated receptor hypothesis and are consistent with a preferential interaction of pentobarbital with the inactivated channel state. As a consequence, actual pentobarbital potency would depend largely on experimental conditions or, in vivo, on the physiological parameters of a particular cell.

The PML gene is linked to a megabase-scale insertion/deletion restriction fragment length polymorphism

The PML gene located on chromosome band 15q22 is involved with the RAR alpha locus (17q21) in a balanced reciprocal translocation uniquely observed in acute promyelocytic leukemia. Physical mapping studies by pulsed-field gel electrophoresis revealed that the PML gene is flanked by two CpG islands that are separated by a variable distance in normal individuals. Several lines of evidence demonstrate that this is the consequence of a large insertion/deletion polymorphism linked to the PML locus: (1) overlapping fragments obtained with a variety of rare-cutting restriction enzymes demonstrated the same variability in distance between the flanking CpG islands; (2) mapping with restriction enzymes insensitive to CpG methylation confirmed that the findings were not a consequence of variable methylation of CpG dinucleotides; (3) the polymorphism followed a Mendelian inheritance pattern. This polymorphism is localized 3' to the PML locus. There are five common alleles, described on the basis of BssHII fragments, ranging from 220 to 350 kb with increments of approximately 30 kb between alleles. Both heterozygous (61%) and homozygous (39%) patterns were observed in normal individuals. Megabase-scale insertion/deletion restriction fragment length polymorphisms are very rare and have been described initially in the context of multigene families. Such structures have been also reported as likely regions of genetic instability. High-resolution restriction mapping of this particular structure linked to the PML locus is underway.

Enormous knowledge base of disease diagnosis criteria

One of the problems in the development of the medical knowledge systems is the limitations of the system's knowledge. It is a common expectation to increase the number of diseases contained in a system. Using a high density knowledge representation method designed by us, we have developed the Enormous Knowledge Base of Disease Diagnosis Criteria (EKBDDC). It contains diagnostic criteria of 1,001 diagnostic entities and describes nearly 4,000 items of diagnostic indicators. It is the core of a huge medical project--the Electronic-Brain Medical Erudite (EBME). This enormous knowledge base was implemented initially on a low-cost popular microcomputer, which can aid in the prompting of typical disease and in teaching of diagnosis. The knowledge base is easy to expand. One of the main goals of EKBDDC is to increase the number of diseases included in it as far as possible using a low-cost computer with a comparatively small storage capacity. For this, we have designed a high density knowledge representation method. Criteria of various diagnostic entities are respectively stored in different records of the knowledge base. Each diagnostic entity corresponds to a diagnostic criterion data set; each data set consists of some diagnostic criterion data values (Table 1); each data is composed of two parts: integer and decimal; the integral part is the coding number of the given diagnostic information, and the decimal part is the diagnostic value of this information to the disease indicated by corresponding record number. For example, 75.02: the integer 75 is the coding number of "hemorrhagic skin rash"; the decimal 0.02 is the diagnostic value of this manifestation for diagnosing allergic purpura. TABULAR DATA, SEE PUBLISHED ABSTRACT. The algebraic sum method, a special form of the weighted summation, is adopted as mathematical model. In EKBDDC, the diagnostic values, which represent the significance of the disease manifestations for diagnosing corresponding diseases, were determined empirically. It is of a great economical, practical, and technical significance to realize enormous knowledge bases of disease diagnosis criteria on a low-cost popular microcomputer. This is beneficial for the developing countries to popularize medical informatics. To create the enormous international computer-aided diagnosis system, one may jointly develop the unified modules of disease diagnosis criteria used to "inlay" relevant computer-aided diagnosis systems. It is just like assembling a house using prefabricated panels.