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Insulin-like growth factor binding protein-4 (IGFBP-4) is an important member of the insulin-like growth factor (IGF) system. The IGFBP-4 has three domains of which the N-terminal sequence is important for the binding of IGF. It acts as a transport protein for IGF-I and IGF-II and modulates their biological effects. There is increasing evidence that IGFBP-4 inhibits IGF-induced cellular growth both in vitro and in vivo. IGFBP-4 can also mediate its actions through a mechanism independent of IGFs. IGFBP-4 level and expression in various tissues are influenced by IGFBP protease, nutrition, several growth factors and hormones. Overexpression of IGFBP-4 in transgenic animal models causes reduced growth of organs containing smooth muscle. Most cancers express IGFBP-4 at levels which correlate with their state of differentiation. However, the effects of IGFBP-4 on tumor growth are uncertain. In vitro studies have shown that overexpression of IGFBP-4 inhibit the growth of some colon cancer cells. Overexpression of IGFBP-4 in vivo has been reported to decrease the growth of prostate cancer. The effect of altered expression of IGFBP-4 in vivo in colon and other cancers needs to be explored as locally available IGFs appear to stimulate mitogenesis. Contents 1. Introduction 2. Structure and binding characteristics of IGFBP-4 3. Biological actions of IGFBP-4 4. Factors controlling IGFBP-4 expression 5.

Intercostal drainage tubes (ie, chest tubes) are inserted to drain the pleural cavity of air, blood, pus, or lymph. The water-seal container connected to the chest tube allows one-way movement of air and liquid from the pleural cavity. The container should not be changed unless it is full, and the chest tube should not be clamped unnecessarily. After a chest tube is inserted, a nurse trained in chest-tube management is responsible for managing the chest tube and drainage system. This entails monitoring the chest-tube position, controlling fluid evacuation, identifying when to change or empty the containers, and caring for the tube and drainage system during patient transport. This article provides an overview of indications, insertion techniques, and management of chest tubes.

Drains have been used in surgery for several years to remove body fluids thereby preventing the accumulation of serous fluid and improving wound healing. Drains may be classified as closed or open systems, and active or passive depending on their intended function. Closed vacuum drains apply negative suction in a sealed environment, producing apposition of tissues and thus promoting healing. Correct assessment of clinical indications might reduce unnecessary usage. This article will introduce the principles and practice of various types of drains and highlight the importance of understanding how surgical drains promote quality patient care.

Methicillin-resistant Staphylococcus aureus (MRSA) is a serious threat to patients in health care facilities and the community. A MRSA infection can be much more severe than other bacterial infections and can be life-threatening. Resistance to common antibiotics makes treating MRSA costly and difficult. Prolonged hospitalization requiring specialized IV antibiotics also has cost implications. Treatment of MRSA can include use of antibiotics; topical therapies such as honey, topical silver, and gentian violet; and bacteriophages. Research is being conducted on new antibiotics and a MRSA vaccine.

High- and low-pressure vacuum drains are commonly used after surgical procedures. High-pressure vacuum drains (ie, sealed, closed-circuit systems) are efficient and allow for easy monitoring and safe disposal of the drainage. Low-pressure vacuum drains use gentle pressure to evacuate excess fluid and air, and are easy for patients to manage at home because it is easy to reinstate the vacuum pressure. Perioperative nurses should be able to identify the various types of commonly used drains and their surgical applications. Nurses should know how to care for drains, how to reinstate the vacuum pressure when necessary, and the potential complications that could result from surgical drain use.

Insulin-like growth factors are known to inhibit apoptosis and promote tumour angiogenesis. Previously we have shown that insulin-like growth factor binding protein-4 (IGFBP-4) gene therapy increased apoptosis and decreased mitosis in colon cancer. In this experiment we used HT-29 colon cancer cells to induce subcutaneous cancers in nude mice and administered either the mammalian expression vector with IGFBP-4 insert or vector only around the tumour site. Three weeks after gene transfer, tumours were harvested and expressions of Bax, Bcl-2 and IGF-I receptor in tumours were determined by Western blotting and immunofluorescence. Micro-vessel counting was performed by immunostaining with CD34 and von Willebrand antibodies. Results showed that tumours treated with IGFBP-4 gene had higher expression of Bax, lower expression of Bcl-2 and IGF-I receptor. Bcl-2 was localised to tumour cell cytoplasm while Bax was expressed both in the interstitial area and cytoplasm. IGFBP-4 treatment also decreased micro-vessel count in tumour tissues. Micro-vessels were mainly located in the periphery and interstitial area. This experiment shows that IGFBP-4 gene therapy increases tumour apoptosis via altering the expressions of Bcl-2 and Bax and decreasing the angiogenesis in colorectal cancer.

Active drains, which work from negative pressure effect, are commonly used to drain closed airtight wounds. Higher negative pressure is used in vacuum assisted wound closure (VAC) (usually -125 mmHg) dressings and in Redivac system (usually -300 mmHg). As far as we know, combinations of Redivac and VAC have not been used. The authors describe a novel combination using the sponge of the VAC dressing and sealed Redivac system to drain an open rectal wound, consequence of a perforation after stapled haemorrhoidopexy.