Impedimetric cell-based biosensor for real-time monitoring of cytopathic effects induced by dengue viruses.

We describe an impedimetric cell-based biosensor constructed from poly-l-lysine (PLL)-modified screen-printed carbon electrode for real-time monitoring of dengue virus (DENV) infection of surface-immobilized baby hamster kidney (BHK-21) fibroblast cells. Cytopathic effects (CPE) induced by DENV-2 New Guinea C strain (including degenerative morphological changes, detachment, membrane degradation and death of host cells), were reflected by drastic decrease in impedance signal response detected as early as ~30 hours post-infection (hpi). In contrast, distinct CPE by conventional microscopy was evident only at ~72 hpi at the corresponding multiplicity of infection (MOI) of 10.

Novel biosensing methodologies for ultrasensitive detection of viruses.

Various infectious diseases caused by the spread of viruses create adverse implications on global biosecurity. Increasing demands for virus surveillance and effective control of the spread of diseases reveal the need for rapid and sensitive virus diagnostic devices. Due to the remarkable sensitivity and specificity of biosensors, they appear as a potential and promising tool for accurate and quantitative detection of viruses.

Impedimetric microbial sensor for real-time monitoring of phage infection of Escherichia coli.

We describe an impedimetric microbial sensor for real-time monitoring of the non-lytic M13 bacteriophage infection of Escherichia coli cells using a gold electrode covalently grafted with a monolayer of lipopolysaccharide specific antibody. After infection, damage to the lipopolysaccharide layer on the outer membrane of E. coli causes changes to its surface charge and morphology, resulting in the aggregation of redox probe, Fe(CN)6(3-/4-) at the electrode surface and thereby increases its electron-transfer rate.

Development of an electrochemical membrane-based nanobiosensor for ultrasensitive detection of dengue virus.

A sensitive membrane-based electrochemical nanobiosensor is developed for the detection of dengue type 2 virus (DENV-2) using nanoporous alumina-modified platinum electrode. Its sensing mechanism relies on the monitoring of electrode's Faradaic current response toward redox probe, ferrocenemethanol, which is sensitive toward the formation of immune complexes within the alumina nanochannels. Anti-DENV-2 monoclonal antibody (clone 3H5, isotype IgG) is used as the biorecognition element in this work.

Membrane-based electrochemical nanobiosensor for Escherichia coli detection and analysis of cells viability.

A sensitive and selective membrane-based electrochemical nanobiosensor is developed for specific quantitative label-free detection of Escherichia coli (E. coli) cells and analysis of viable but nonculturable (VBNC) E. coli cells which remain mostly undetected using current methods.

Mini-incision double eyelidplasty.

Background: Blepharoplasty in Asia is almost synonymous with double-eyelid surgery, which refers to the creation of a palpebral fold by supratarsal fixation in patients with no visible or a low supratarsal crease. The best way to develop the supratarsal crease is to achieve a permanent attachment between the dermis and the levator aponeurosis/tarsal plate at an appropriate height.

Objectives: The authors describe the results of their mini-incision technique for developing a double eyelid.

Nanoarray membrane sensor based on a multilayer design for sensing of water pollutants.

A ubiquitous electrochemical sensor which can detect pollutants in nonconducting aqueous solutions is prepared using a triple layer design, comprising a polyelectrolyte entrapped within micrometer-length nanochannels and sandwiched between two nanometer-thick electrode layers. Replacement of the polyelectrolyte with an enzyme-polyelectrolyte mixture within the nanochannels confers excellent biosensing characteristics. Its superior analytical performance of quantitating copper ions and formaldehyde at trace levels without additional sample treatment steps is demonstrated in freshwater samples derived from a local reservoir.

Evaluation of MRI findings after polyacrylamide gel injection for breast augmentation.

Objective: Polyacrylamide gel injection mammoplasty has recently been used for breast augmentation. However, many complications have been reported including complications that in some patients resulted in the need for mastectomy. This article reviews the MRI appearances of various complications of polyacrylamide gel injection mammoplasty including breast asymmetry; intramammary or extramammary gel displacement, including intrathoracic extension; and glandular atrophy, inflammation, and infection resulting in mastectomy.

Nipple-areola reconstruction in autologous breast reconstruction: Chinese patients' perspective.

Twenty-five consecutive patients who had nipple-areola reconstruction (NAR) using a modified S dermal-fat flap technique in the Division of Plastic Surgery, Department of Surgery, Kwong Wah Hospital, between 1995 and 2000 were studied. The nipple projection and sensation (to light touch and pinprick) were assessed by a designated surgeon who was not involved in the reconstructive process. This was followed by a questionnaire on the patients' perception of the various physical characteristics of the reconstructed nipple-areola complex (NAC) when in the nude.