Dual roles of tumour cells-derived matrix metalloproteinase 2 on brain tumour growth and invasion.

BACKGROUND: A previous study on a murine astrocytoma cell-line ALTS1C1 showed a highly invasive pattern similar to clinical anaplastic astrocytoma in vivo. This cell-line also expressed a high level of matrix metalloproteinase 2 (MMP2). This study aimed to verify the role of MMP2 in brain tumour progression. METHODS: ALTS1C1 and MMP2 knockdown (MMP2kd) cells were inoculated intracranially, and tumour microenvironment was assessed by immunohistochemistry staining. RESULTS: MMP2 expression was co-localised with CD31-positive cells at invading the tumour front and correlated with an invasive marker GLUT-1. The suppression of MMP2 expression prolonged the survival of tumour-bearing mice associated with tumours having smoother tumour margins, decreased Ki67-proliferating index, and down-regulated GLUT-1 antigen. Although the reduction of MMP2 expression did not alter the vessel density in comparison to parental ALTS1C1 tumours, vessels in MMP2kd tumours were less functional, as evidenced by the low ratio of pericyte coverage and reduction in Hoechst33342 dye perfusion. CONCLUSIONS: This study illustrated that tumour-derived MMP2 has at least two roles in tumour malignancy; to enhance tumour invasiveness by degrading the extracellular matrix and to enhance tumour growth by promoting vessel maturation and function.

Outcome after conservative management for mixed urinary incontinence.

AIM: Recommended initial treatment for mixed urinary incontinence involves behavioral therapy, and drug and pelvic floor muscle exercises. Our objective is to evaluate the outcome of these conservative treatments in our patients with mixed urinary incontinence. METHODS: A retrospective review was conducted in patients with mixed urinary incontinence who were offered sequential conservative treatment modalities comprised of medication and physiotherapy. Outcome was defined as a score of 1 or less for questions 2 and 3 on the six-item Urodynamic Distress Inventory (UDI-6) and seven-item Incontinence Impact Questionnaire, in addition to clinical symptomatic improvement with no urgency, urge incontinence and voiding frequency of less than eight times per 24 h on a 3-day bladder diary after treatment. Treatment outcome of patients opting for medication plus physiotherapy (M + P) were analyzed against patients preferring medication only (M). RESULTS: Sixty-two mixed urinary incontinent patients received an initial treatment with conservative measures with mean follow-up of 14 months. A total of 61.2% (30/49) and 56.3% (9/13) subjects had improved symptoms in the M + P and M group, respectively. There was significant improvement in UDI-6 total score in the M + P group after conservative treatment, despite no significant difference when compared to the M group. Only 6.45% required subsequent anti-incontinence surgery after conservative treatment, amongst whom only half showed improvement after the surgery. CONCLUSION: Combined treatment with medication and physiotherapy is highly recommended for patients with mixed urinary incontinence. Conservative measures should still precede any surgical intervention. Further studies are needed to evaluate the long-term efficacy.

Turn over the new leaf of the treatment in peptic ulcer bleeding: a review of the literature.

Peptic ulcer bleeding is the most common cause of upper gastrointestinal bleeding, which has a high mortality risk. The standard therapy for acute peptic ulcer bleeding combines medication administration and endoscopic therapies. Both pharmacologic and endoscopic therapies have developed continuously in the past few decades. Proton pump inhibitors (PPIs) already reached a high efficacy in ulcer healing and have been widely used in the past few decades. Endoscopic hemostasis, which includes local epinephrine injection, heater probe coagulation, use of hemostatic clips, and/or band ligation, is highly effective with an overall hemostatic success rate of 85%-90%. However, 10%-20% of patients could not be cured by the current standard combination treatment. Recurrent ulcer bleeding, despite an initial successful hemostasis, is also a big problem for longer hospitalization stays, higher mortality, and higher complication rates, especially for malignant ulcer bleeding. How to manage all types of peptic ulcer bleeding and how to prevent early recurrent peptic ulcer bleeding remain unresolved clinical problems. Recently, several novel medications and endoscopic methods have been developed. Potassium competitive acid blockers have shown a stronger and longer acid suppression than PPI. Hemostatic powder spray and hemostatic gel emulsion are novel hemostatic weapons with emerging evidence, which are potential missing pieces of the puzzle. This literature review will go through the development of endoscopic hemostasis to the prospects of novel endoscopic treatments.

Factors affecting degradation of dimethyl sulfoxide (DMSO) by fluidized-bed Fenton process.

In this study, the target compound is dimethyl sulfoxide (DMSO), which is used as a photoresist stripping solvent in the semiconductor and thin-film transistor liquid crystal display (TFT-LCD) manufacturing processes. The effects of the operating parameters (pH, Fe(2+) and H2O2 concentrations) on the degradation of DMSO in the fluidized-bed Fenton process were examined. This study used the Box-Behnken design (BBD) to investigate the optimum conditions of DMSO degradation. The highest DMSO removal was 98 % for pH 3, when the H2O2 to Fe(2+) molar ratio was 12. At pH 2 and 4, the highest DMSO removal was 82 %, when the H2O2 to Fe(2+) molar ratio was 6.5. The correlation of DMSO removal showed that the effect of the parameters on DMSO removal followed the order Fe(2+) > H2O2 > pH. From the BBD prediction, the optimum conditions were pH 3, 5 mM of Fe(2+), and 60 mM of H2O2. The difference between the experimental value (98 %) and the predicted value (96 %) was not significant. The removal efficiencies of DMSO, chemical oxygen demand (COD), total organic carbon (TOC), and iron in the fluidized-bed Fenton process were higher than those in the traditional Fenton process.