Focal point technology: Controlling treatment depth and pattern of skin injury by a novel highly focused laser.

Background: Selective photothermolysis has limitations in efficacy and safety for dermal targets. We describe a novel concept using scanned focused laser microbeams for precise control of dermal depth and pattern of injury, using a 1550 nm laser that generates an array of conical thermal zones while minimizing injury to the epidermis.

Objective: To characterize the conical thermal zones in vivo and determine safe starting parameters to transition to a second phase to explore potential clinical indications.

The Basic Mechanism of Hair Growth Stimulation by Adipose-derived Stem Cells and Their Secretory Factors.

Background: Adipose-derived stem cells (ADSCs) are mesenchymal stem cells (MSCs) within the stromal vascular fraction of subcutaneous adipose tissue. ADSCs secrete growth factors and other proteins, and have been used to regenerate skin with satisfactory results.

Objective: This review focuses on the effect of ADSCs and their secretory factors on the stimulation of hair growth in vitro, ex vivo and in vivo.

Hsp70 Knockdown by siRNA Decreased Collagen Production in Keloid Fibroblasts.

Purpose: There are currently no consistently effective treatments for the excessive collagen produced by keloid fibroblasts. Previously, we reported that heat shock protein 70 (Hsp70) is up-regulated in keloid fibroblasts and keloid tissue. We, therefore, investigated whether Hsp70 is related to excessive collagen production in keloid fibroblasts.

Fractional epidermal grafting in combination with laser therapy as a novel approach in treating radiation dermatitis.

Radiation injury to the skin is a major source of dysfunction, disfigurement, and complications for thousands of patients undergoing adjunctive treatment for internal cancers. Despite the great potential for affecting quality of life, radiation injury has received little attention from dermatologists and is primarily being managed by radiation oncologists. During our volunteer work in Vietnam, we encountered numerous children with significant scarring and depigmentation of skin from the outdated use of radioactive phosphorus P32 in the treatment of hemangiomas.

Cutaneous drug delivery: an update.

Cutaneous delivery of therapeutics represents a proven and attractive option for treating a variety of dermatologic conditions with minimal systemic side effects. Although there have been many innovations in drug delivery systems, the number of effective cutaneous drugs remains small, primarily because of the stratum corneum permeability barrier. Overcoming this barrier safely and reversibly to deliver large hydrophilic drugs cutaneously is one of the major challenges in the field of dermatologic therapy.

Design and fabrication of human skin by three-dimensional bioprinting.

Three-dimensional (3D) bioprinting, a flexible automated on-demand platform for the free-form fabrication of complex living architectures, is a novel approach for the design and engineering of human organs and tissues. Here, we demonstrate the potential of 3D bioprinting for tissue engineering using human skin as a prototypical example. Keratinocytes and fibroblasts were used as constituent cells to represent the epidermis and dermis, and collagen was used to represent the dermal matrix of the skin.

BCL2A1 is a lineage-specific antiapoptotic melanoma oncogene that confers resistance to BRAF inhibition.

Although targeting oncogenic mutations in the BRAF serine/threonine kinase with small molecule inhibitors can lead to significant clinical responses in melanoma, it fails to eradicate tumors in nearly all patients. Successful therapy will be aided by identification of intrinsic mechanisms that protect tumor cells from death. Here, we used a bioinformatics approach to identify drug-able, "driver" oncogenes restricted to tumor versus normal tissues.

The brain circuitry mediating antipruritic effects of acupuncture.

Itch is an aversive sensory experience and while systemic therapies, such as acupuncture, have shown promise in alleviating itch in patients suffering from chronic itch, their antipruritic mechanisms are unknown. As several lines of evidence implicate brain-focused mechanisms, we applied functional magnetic resonance imaging and our validated temperature-modulation itch model to evaluate the underlying brain circuitry supporting allergen-induced itch reduction in atopic dermatitis patients by acupuncture, antihistamine, and respective placebo treatments. Brain response to allergen itch demonstrated phase dependency.

YY1 regulates melanocyte development and function by cooperating with MITF.

Studies of coat color mutants have greatly contributed to the discovery of genes that regulate melanocyte development and function. Here, we generated Yy1 conditional knockout mice in the melanocyte-lineage and observed profound melanocyte deficiency and premature gray hair, similar to the loss of melanocytes in human piebaldism and Waardenburg syndrome. Although YY1 is a ubiquitous transcription factor, YY1 interacts with M-MITF, the Waardenburg Syndrome IIA gene and a master transcriptional regulator of melanocytes.

Clinical, epidemiological and virological features of Dengue virus infections in Vietnamese patients presenting to primary care facilities with acute undifferentiated fever.

Objectives: To explore clinical and virological characteristics and describe the epidemiology of dengue in patients who presented with acute undifferentiated fever (AUF) at primary health centers (PHC) in Binh Thuan Province, Vietnam.

Methods: A prospective observational study was conducted from 2001 to 2006 to study the aetiology in AUF patients. Demographic and clinical information was obtained, and dengue polymerase chain reaction (RT-PCR) and serology were performed on a random selection of patients.

Seroepidemiology of leptospirosis in southern Vietnamese children.

Objective: To estimate the seroprevalence of human leptospirosis in southern Vietnam.

Methods: All pupils (n=961) of two primary schools in two communes in southern Vietnam were screened for the presence of serum Leptospira immunoglobulin (Ig)G. Leptospira IgM was tested in 92 randomly selected samples.

Seroprevalence of dengue antibodies, annual incidence and risk factors among children in southern Vietnam.

Dengue is highly endemic in southern Vietnam and all four serotypes of dengue virus have already been identified. To determine the age-specific prevalence of dengue and associated risk factors, we conducted a serological study at two primary schools and assessed risk factors by analysing children's questionnaires and household surveys. Sera were collected from 961 primary schoolchildren in Binh Thuan Province and tested for the presence of dengue virus serum antibodies using an indirect immunoglobulin G (IgG) enzyme-linked immunosorbent assay (ELISA).

Nanoparticle-aptamer bioconjugates: a new approach for targeting prostate cancer cells.

Nucleic acid ligands (aptamers) are potentially well suited for the therapeutic targeting of drug encapsulated controlled release polymer particles in a cell- or tissue-specific manner. We synthesized a bioconjugate composed of controlled release polymer nanoparticles and aptamers and examined its efficacy for targeted delivery to prostate cancer cells. Specifically, we synthesized poly(lactic acid)-block-polyethylene glycol (PEG) copolymer with a terminal carboxylic acid functional group (PLA-PEG-COOH), and encapsulated rhodamine-labeled dextran (as a model drug) within PLA-PEG-COOH nanoparticles.

Characterization of chemisorbed hyaluronic acid directly immobilized on solid substrates.

Hyaluronic acid (HA) has a number of potential biomedical applications in drug delivery and tissue engineering. For these applications, a prerequisite is to understand the characteristic of HA films directly immobilized to solid substrates. Here, we demonstrate that high molecular weight HA can be directly immobilized onto hydrophilic substrates without any chemical manipulation, allowing for the formation of an ultrathin chemisorbed layer.

A reversibly switching surface.

We report the design of surfaces that exhibit dynamic changes in interfacial properties, such as wettability, in response to an electrical potential. The change in wetting behavior was caused by surface-confined, single-layered molecules undergoing conformational transitions between a hydrophilic and a moderately hydrophobic state. Reversible conformational transitions were confirmed at a molecular level with the use of sum-frequency generation spectroscopy and at a macroscopic level with the use of contact angle measurements.