Integration of DNA into bacterial chromosomes from plasmids without a counter-selection marker.

Most bacteria can only be transformed with circular plasmids, so robust DNA integration methods for these rely upon selection of single-crossover clones followed by counter-selection of double-crossover clones. To overcome the limited availability of heterologous counter-selection markers, here we explore novel DNA integration strategies that do not employ them, and instead exploit (i) activation or inactivation of genes leading to a selectable phenotype, and (ii) asymmetrical regions of homology to control the order of recombination events. We focus here on the industrial biofuel-producing bacterium Clostridium acetobutylicum, which previously lacked robust integration tools, but the approach we have developed is broadly applicable. Large sequences can be delivered in a series of steps, as we demonstrate by inserting the chromosome of phage lambda (minus a region apparently unstable in Escherichia coli in our cloning context) into the chromosome of C. acetobutylicum in three steps. This work should open the way to reliable integration of DNA including large synthetic constructs in diverse microorganisms. © 2011 The Author(s)

Hormonal control of the metabolic machinery of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most fatal malignancies worldwide. It is an aggressive cancer with low cure rate, frequent metastasis, and highly resistant to conventional chemotherapies. Better knowledge regarding the molecular and metabolic alterations in HCC will be instrumental to the development of novel therapeutic interventions against HCC. In the August 2015 issue of Hepatology, Nie et al. reports an important molecular pathway that contributes to the Warburg Effect in HCC. They have beautifully demonstrated that the loss of a component of a hormonal system, the mineralocorticoid receptor (MR), reprogrammed the metabolic machinery of HCC cells to aerobic glycolysis through the miR-338-3p-PKL/R axis. The implication could be that in addition to drugs that directly target the metabolic enzymes in cancer cells, more translational efforts could be focused on the development of drugs that involve the activation of the MR-aldosterone system or other hormonal systems to target the Warburg effect.published_or_final_versio

Cost-effectiveness analysis of newborn screening for organic acidemias in Hong Kong

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The Chinese version of the pelvic pain and urgency / frequency symptom scale: a useful assessment tool for street-ketamine abusers with lower urinary tract symptoms

OBJECTIVE: To investigate the use of a translated Chinese version of the pelvic pain and urgency/frequency symptom scale as an assessment and prognostic tool to evaluate the severity of street-ketamine-associated lower urinary tract symptoms and their reversibility after abstinence. DESIGN: Cross-sectional study. SETTING: A special designated out-patient clinic in a regional hospital in Hong Kong. PARTICIPANTS: There were 50 patients with street-ketamine-associated lower urinary tract symptoms and 20 healthy individuals. MAIN OUTCOME MEASURES: Reliability and validity of the questionnaire; frequency of individual lower urinary tract symptoms, cystoscopic, urodynamic and radiological abnormalities, and their correlation with pelvic pain and the urgency/frequency score. RESULTS: The test-retest reliability coefficient was 0.755 (P<0.001). Cronbach's alpha was 0.974. Mann-Whitney U test proved the discriminatory ability of the questionnaire (P<0.001). Patients with specific lower urinary tract symptoms had a higher mean pelvic pain and urgency/frequency total score compared to those without them: frequency (23.8 vs 17.3), nocturia (22.4 vs 14.0), urgency (22.5 vs 15.1), dysuria (22.7 vs 13.3), and haematuria (24.8 vs 16.2). The number of daytime voids and nocturia episodes correlated well with pelvic pain and urgency/frequency scores. With an increasing score, the likelihood of having cystitis changes, urodynamic abnormalities and hydronephrosis increased, while the cystometrically determined bladder capacity decreased. None of the patients with a score of 16 or below had urodynamic abnormality or hydronephrosis. The mean score change in the abstinence group was -4.33, versus +3.33 in their counterparts. CONCLUSIONS: The Chinese version of the pelvic pain and urgency/frequency questionnaire is reliable and valid for assessment in patients with street-ketamine-associated lower urinary tract symptoms. The pelvic pain and urgency/frequency score correlates well with symptom severity as well as endoscopic, urodynamic and radiological abnormalities in patients with street-ketamine-associated lower urinary tract symptoms. A cut-off total pelvic pain and urgency/frequency score of 17 may suggest more serious urological sequelae from ketamine abuse. Abstinence from ketamine reduced lower urinary tract symptoms, but the extent of reversibility of urinary tract damage is yet to be evaluated.published_or_final_versio

Functional characterization of liver-enriched transcription factor CREB-H (poster 1989)

Tissue-Specific Gene Expression (1985-2002) Sessionpublished_or_final_versio

p63 is a key regulator of iRHOM2 signalling in the keratinocyte stress response.

Hyperproliferative keratinocytes induced by trauma, hyperkeratosis and/or inflammation display molecular signatures similar to those of palmoplantar epidermis. Inherited gain-of-function mutations in RHBDF2 (encoding iRHOM2) are associated with a hyperproliferative palmoplantar keratoderma and squamous oesophageal cancer syndrome (termed TOC). In contrast, genetic ablation of rhbdf2 in mice leads to a thinning of the mammalian footpad, and reduces keratinocyte hyperproliferation and migration. Here, we report that iRHOM2 is a novel target gene of p63 and that both p63 and iRHOM2 differentially regulate cellular stress-associated signalling pathways in normal and hyperproliferative keratinocytes. We demonstrate that p63-iRHOM2 regulates cell survival and response to oxidative stress via modulation of SURVIVIN and Cytoglobin, respectively. Furthermore, the antioxidant compound Sulforaphane downregulates p63-iRHOM2 expression, leading to reduced proliferation, inflammation, survival and ROS production. These findings elucidate a novel p63-associated pathway that identifies iRHOM2 modulation as a potential therapeutic target to treat hyperproliferative skin disease and neoplasia

Cholestatic jaundice caused by sequential carbimazole and propylthiouracil treatment for thyrotoxicosis

A 36-year-old Chinese man presented to the Queen Mary Hospital in August 1999 with a 2-week history of jaundice due to propylthiouracil treatment for thyrotoxicosis. He had previously received carbimazole but had developed an urticarial skin rash after 2 weeks of treatment. The patient developed liver failure and fulminant pneumonitis shortly after hospital admission. Despite receiving treatment with broad-spectrum antibiotics and intravenous immunoglobulin, he died 11 days after the onset of the respiratory symptoms. Postmortem examination using electron microscopy showed typical glycogen bodies within the cytoplasm of the hepatocytes, which corresponded to eosinophilic cytoplasmic inclusion bodies visible under light microscopy. Immunohistochemical studies of the inclusion bodies were positive for carcinoembryonic antigen and albumin, and negative for fibrinogen, complement protein C3, immunoglobulins G, M, and A, α-fetoprotein, and α-1-antitrypsin. This is the first report of a patient who received two sequential antithyroid drugs and developed predominate cholestasis with unique histological features. Extreme caution should be taken when a patient develops allergy to one type of antithyroid drug, because cross-reactivity may develop to the other type.published_or_final_versio

EZH2-Mediated H3K27me3 Is Involved in Epigenetic Repression of Deleted in Liver Cancer 1 in Human Cancers

Enhancer of zeste homolog 2 (EZH2), the histone methyltransferase of the Polycomb Repressive complex 2 catalyzing histone H3 lysine 27 tri-methylation (H3K27me3), is frequently up-regulated in human cancers. In this study, we identified the tumor suppressor Deleted in liver cancer 1 (DLC1) as a target of repression by EZH2-mediated H3K27me3. DLC1 is a GTPase-activating protein for Rho family proteins. Inactivation of DLC1 results in hyper-activated Rho/ROCK signaling and is implicated in actin cytoskeleton reorganization to promote cancer metastasis. By chromatin immunoprecipitation assay, we demonstrated that H3K27me3 was significantly enriched at the DLC1 promoter region of a DLC1-nonexpressing HCC cell line, MHCC97L. Depletion of EZH2 in MHCC97L by shRNA reduced H3K27me3 level at DLC1 promoter and induced DLC1 gene re-expression. Conversely, transient overexpression of GFP-EZH2 in DLC1-expressing Huh7 cells reduced DLC1 mRNA level with a concomitant enrichment of EZH2 on DLC1 promoter. An inverse relation between EZH2 and DLC1 expression was observed in the liver, lung, breast, prostate, and ovarian cancer tissues. Treating cancer cells with the EZH2 small molecular inhibitor, 3-Deazaneplanocin A (DZNep), restored DLC1 expression in different cancer cell lines, indicating that EZH2-mediated H3K27me3 epigenetic regulation of DLC1 was a common mechanism in human cancers. Importantly, we found that DZNep treatment inhibited HCC cell migration through disrupting actin cytoskeleton network, suggesting the therapeutic potential of DZNep in targeting cancer metastasis. Taken together, our study has shed mechanistic insight into EZH2-H3K27me3 epigenetic repression of DLC1 and advocated the significant pro-metastatic role of EZH2 via repressing tumor and metastasis suppressors.published_or_final_versio

Recommending anchor points in structure-preserving hypertext document retrieval

Traditional WWW search engines index and recommend individual Web pages to assist users in locating relevant documents. Users are often overwhelmed by the large answer set recommended by the search engines. The logical starting point of the hyper-document is thus hidden among the large basket of matching pages. Users need to spend a lot of effort browsing through the pages to locate the starting point, a very time consuming process. This paper studies the anchor point indexing problem. The anchor points of a given user query is a small set of key pages from which the larger set of documents that are relevant to the query can be easily reached. The use of anchor points help solve the problems of huge answer set and low precision suffered by most search engines by considering the hyper-link structures of the relevant documents, and by providing a summary view of the result set.published_or_final_versio

Resection of T4 hepatocellular carcinomas with adjacent structures, is it justified?

postprin