The level and pattern of physical activity among fifth-grade students in Ho Chi Minh City, Vietnam.

OBJECTIVES: Despite the benefits of physical activity (PA), a significant proportion of children do not meet physical activity guidelines (PAGs). However, most studies were among secondary-school-aged youth and relied on PA self-report. In addition, information regarding children's PA behaviors during specific segments of day/week is not usually collected. This study, therefore, investigated the level and pattern of PA among fifth-grade students in Ho Chi Minh City (HCMC), Vietnam. STUDY DESIGN: A complex cross-sectional survey was conducted on a representative sample of 619 fifth-grade students in eight public schools in urban areas of HCMC in 2016. METHODS: Demographic/anthropometric characteristics were measured using standard protocols. PA was measured using pedometers. After-school activities were measured using the Previous Day Physical Activity Recall questionnaire. Survey procedures with sampling weights were used for analyses. RESULTS: Approximately 18% of children met the PAG; 52.7% were overweight (OW)/obese (OB). On average, students recorded about 8800 steps/day. Boys were more active than girls at school and on weekdays. Students were more active at school on physical education (PE) days vs non-PE days and weekdays vs weekends. OW/OB students were more active at school on PE days. After-school PAs differed between boys and girls, whereas sedentary activities were popular among both the genders. CONCLUSIONS: Most fifth-grade students had insufficient PA levels. Patterns of PA are different at various times during the day and week. The finding emphasized an urgent need for interventions to improve children's PA and obesity in this area.

Trade patterns facilitating highly pathogenic avian influenza virus dissemination in the free-grazing layer duck system in Vietnam.

Highly pathogenic avian influenza (HPAI) viruses continue to threaten smallholder poultry producers in several South-east Asian countries, including Vietnam. In particular, the free-grazing duck system has been repeatedly highlighted as a major risk factor for HPAI outbreaks. Free-grazing ducks, which scavenge on rice paddies after the harvest, account for a large proportion of the duck population in Vietnam and the wider South-east Asian region. However, the structure and dynamics of the free-grazing duck production from farm to consumption has not been described for Vietnam. In this study, we used a value chain approach to provide a complete picture of the actors involved in the production and marketing of free-grazing duck eggs and spent layer ducks, as well as to investigate the governance structure of this food system. Group interviews and key informant interviews were conducted in two provinces located in the Mekong River Delta (MRD) and the Red River Delta (RRD). The results presented here highlight similarities and differences in farming and trade practices between the two provinces. The trade of spent layer ducks involved large volumes of live ducks being sent to China and Cambodia for consumption, generating a substantial risk of transboundary spread of pathogens, including HPAI viruses. We describe the major role of "duck yards", which act as hubs in the northbound trade of spent layer ducks. These yards should be considered as essential links in the value chain of spent layer ducks when considering HPAI surveillance and control. The veterinary authorities are only marginally involved in the value chain activities, and their influence could be strengthened by increasing surveillance activities for instance in duck yards. Last, we discuss the dynamics of the duck value chain and further implications for future HPAI management policies.

Month-6 primary outcomes of the READ-3 study (Ranibizumab for Edema of the mAcula in Diabetes-Protocol 3 with high dose).

PURPOSE: To compare 2.0 mg ranibizumab (RBZ) injections with 0.5 mg RBZ for eyes with center-involved diabetic macular edema (DME) and a central subfield thickness (CFT) of ≥250 µm on time-domain optical coherence tomography.DesignRandomized, controlled, multicenter clinical trial. METHODS: Eligible eyes were randomized in a 1:1 ratio to 0.5 mg (n=77) or 2.0 mg (n=75) RBZ. Study eyes received 6-monthly injections.Main outcome measuresThe primary outcome measure was the mean change in best corrected visual acuity (BCVA) at month 6. Secondary outcomes included the incidence and severity of systemic and ocular adverse events and the mean change in CFT from baseline. RESULTS: In all, 152 eyes (152 patients) were randomized in the study. At month 6, the mean improvement from baseline BCVA was +9.43 letters in the 0.5 mg RBZ group and +7.01 letters in the 2.0 mg RBZ group (P=0.161). At month 6, one death occurred in the 0.5 mg RBZ group and three deaths in the 2.0 mg RBZ group, all due to myocardial infarction in subjects with a prior history of heart disease. Mean CFT was reduced by 168.58 µm in the 0.5 mg RBZ group and by 159.70 µm in the 2.0 mg RBZ group (P=0.708). CONCLUSIONS: There was no statistically significant difference in the mean number of letters gained between the 0.5 and 2.0 mg RBZ groups through month 6. In this DME study population, high-dose RBZ does not appear to provide additional benefit over 0.5 mg RBZ.

Therapies in Development for Non-Infectious Uveitis.

Uveitis represents a spectrum of diseases characterized by ocular inflammation that leads to significant visual loss if left untreated. Adequate, long-term control of inflammation with minimal systemic and local adverse effects is the preferred strategy for treating patients with uveitis. Pharmacotherapy for uveitis consists mainly of corticosteroids in various formulations such as topical, local, intraocular and systemic. However, monotherapy with corticosteroids is often unacceptable due to serious adverse effects on various organ systems. There exist limitations with the use of steroid-sparing systemic immunosuppressive agents, as these medications may have significant adverse events and a narrow therapeutic window. Thus, newer molecular targets that act on various steps of the inflammatory pathway appear to be promising emerging strategies for treating uveitis. Specially designed monoclonal antibodies in development can potentially halt the inflammatory processes resulting in remission of the disease. In the index review, novel molecular agents and biological therapies that have shown promising efficacy and safety data in preclinical and clinical studies have been summarized. In addition, new drug delivery systems that may ensure high intraocular therapeutic levels of pharmacologic agents have been highlighted.

Longitudinal comparison of visual acuity as measured by the ETDRS chart and by the potential acuity meter in eyes with macular edema, and its relationship with retinal thickness and sensitivity.

PURPOSE: To evaluate the relationship between visual acuity as measured by the Early Treatment Diabetic Retinopathy Study (ETDRS) chart and by the potential acuity meter (PAM) with retinal thickness and sensitivity measured by a combined microperimetry/optical coherence tomography system (OCT). METHODS: Forty-four patients with macular edema (ME) were included in a prospective observational study. Visual acuity (VA) was assessed using the ETDRS chart (with best correction) as well as by the PAM. Retinal thickness and sensitivity was measured by an automatic fundus perimetry/tomography system. RESULTS: Best-corrected VA using the ETDRS chart ranged from 20/20 to 20/400 (median: 20/50). VA measured by the PAM without correction ranged from 20/20 to 20/400 (median: 20/40). The mean retinal thickness was 369.57 µm (s.d.: 140.28 µm) on spectral domain-OCT and the mean retinal sensitivity was 8.12 decibels (dB) (s.d.: 5.78 dB). The mean LogMAR value using the ETDRS chart was 0.43, whereas it was 0.38 using the PAM (P-value: 0.009). CONCLUSIONS: VA values measured by the PAM were statistically significantly better than those measured by the ETDRS chart in eyes with ME secondary to various retinal vascular and uveitic diseases. VA measured by the PAM may be a more sensitive predictor of macular function than that obtained by ETDRS testing in eyes with ME.

Association of retinal vessel calibre and visual outcome in eyes with diabetic macular oedema treated with ranibizumab.

PURPOSE: The study aims to identify the association between the baseline retinal vascular calibre and visual outcome of patients with diabetic macular oedema (DMO) treated with intravitreal ranibizumab. METHODS: The 1-M field (as defined in the ETDRS study) of the digital colour fundus photographs of DMO patients who had been treated primarily with ranibizumab in a clinical trial was assessed. Of the 84 patients, 25 had gradable retinal photographs that could be subjected to analyses by the Interactive Vessel Analysis (IVAN) software at baseline. The average retinal vascular calibre of the six largest venules (CRVE) and the six largest arterioles (CRAE) in the peripapillary area (0.5 and 1 disc diameter from the optic disc margin) was measured. The relationship between CRVE and CRAE at baseline and the change in visual acuity at month 12 was assessed using the Mann-Whitney U test. RESULTS: Ten eyes from 10 patients who had shown an improvement of ≥2 lines of best corrected visual acuity (BCVA) at month 12 had a wider baseline CRVE (248.3±24.5 µm) compared with the 15 eyes from 15 patients who did not show the improvement of ≥2 lines (226.6±44.8 µm, P<0.05). The baseline CRAE did not differ significantly in these patients (156.1±22.7 vs 142±17.5 µm, P=0.17). CONCLUSIONS: A wider baseline retinal venular calibre may be a predictor of better visual outcome in DMO eyes treated with ranibizumab. Further prospective studies with a larger sample size and a broader range of disease severity and visual acuity are needed to confirm this finding.

Factors affecting visual outcomes in patients with diabetic macular edema treated with ranibizumab.

PURPOSE: To identify factors associated with visual outcomes in patients with diabetic macular edema (DME) treated with ranibizumab (RBZ) in the Ranibizumab for Edema of the mAcula in Diabetes-Protocol 2 (READ-2) Study. PATIENTS AND METHODS: Optical coherence tomography scans, fundus photographs, and fluorescein angiograms (FAs) were graded and along with baseline characteristics were correlated with month (M) 24 visual outcome of best-corrected visual acuity (BCVA) ≤20/100 (poor outcome) vs >20/100 (better outcome). RESULTS: Of 101 patients with a M20 visit or beyond, 27 (27%) had BCVA ≤20/100. Comparison of patients with or without poor outcome showed mean baseline BCVA of 16.8 letters (20/125) in the former compared with 30.4 letters (20/63; P<0.001). Mean change in BCVA between baseline and M24 was -2.6 letters in the poor outcome group compared with +9.8 letters (P<0.001). Foveal thickness (FTH) at M24 was 374.1 µm in the poor outcome group compared with 268.8 µm (P<0.01), a difference driven by 14 patients with mean FTH of 450.3 µm. Foveal atrophy occurred in 65% (11/17) in the poor outcome group compared with 17%(12/71, P=0.001). Persistent edema was noted in 52% (14/27) of patients with poor outcome. Laser scars near foveal center were significantly more common in patients with poor outcome who did not have edema vs those who did (78% (7/9) vs 23% (3/13) P=0.03). CONCLUSION: Poor baseline BCVA (≤20/125) in DME patients predicts poor visual outcome (≤20/100) after 2 years of treatment with RBZ and/or focal/grid laser, often due to foveal atrophy and/or persistent edema.

Safety, tolerability, and bioavailability of topical SAR 1118, a novel antagonist of lymphocyte function-associated antigen-1: a phase 1b study.

PURPOSE: A growing body of evidence points to a role for inflammation mediated by lymphocyte function-associated antigen-1 (LFA-1) and its ligand intercellular adhesion molecule-1 in the pathogenesis of diabetic macular oedema. This phase 1b clinical trial assessed the safety, tolerability, and pharmacokinetics of topically administered SAR 1118, a novel LFA-1 antagonist, in human subjects. METHODS: In this prospective, randomized, double-masked trial, 13 subjects scheduled for vitrectomy received one of three concentrations of topical SAR 1118 (0.1, 1.0, or 5.0%) twice daily for 1 week before surgery. Undiluted aqueous and vitreous samples were collected at surgery and analysed for the concentration of the medication. RESULTS: All subjects completed the entire course of medication. The only adverse events reported were instillation site irritation (4/13, 31%) and dysgeusia (3/13, 23%). These were mild and transient, occurring at the highest dose. Mean concentrations (ng/ml) of SAR 1118 in the aqueous humour were 0.25, 37.2, and 101.1 for the 0.1%, 1.0%, and 5.0% dose groups, respectively. SAR 1118 was below the level of detection (0.5 ng/ml) for all vitreous samples except in a single subject who had a history of prior vitrectomy and a dislocated intraocular lens. CONCLUSIONS: Topical SAR 1118 was safe and well tolerated, and dose-dependent levels of drug were detected in aqueous. However, vitreous levels were below the threshold of detection with the concentrations tested. Further investigation of this medication for posterior segment applications would require intravitreal delivery or chemical modification of the drug.

Spectral- and time-domain optical coherence tomography measurements of macular thickness in normal eyes and in eyes with diabetic macular edema.

PURPOSE: To report macular thickness values in normal eyes and eyes with diabetic macular edema (DME) using time-domain (TD) and spectral-domain (SD) optical coherence tomography (OCT), and to derive a conversion equation. METHODS: The index study was a prospective investigation conducted on 80 eyes from 40 normal subjects and 130 eyes from 118 patients with DME seen in our clinic. Retinal thickness values from the central 1 mm of the macula and surrounding four ETDRS subfields were acquired using TD-OCT (Stratus OCT) and SD-OCT (SPECTRALIS HRA+OCT). Measurements of the central (C) subfield from both devices were used to derive a conversion equation. The equation was used to predict SD-OCT values using measurements from TD-OCT. Agreement between predicted and actual SD-OCT measurements was assessed. RESULTS: In normal eyes, the mean difference between TD-OCT and SD-OCT measurements of the C subfield was 76 µm (CI(95)=74 and 77, respectively). The conversion equation, y=1.029x+72.49, was derived. In eyes with DME, using the equation, SPECTRALIS-predicted values were 5% higher than actual measurements, with 95% of predicted values falling within 9% of the actual measurements. Relocating SD-OCT grids to match the location on TD-OCT resulted in predicted values falling within 7% of actual measurements. CONCLUSIONS: The percent difference between actual thickness measurements from SPECTRALIS and predicted thickness measurements, using the conversion equation, was within reported limits of repeatability of Stratus in eyes with DME. Our equation may help correlate OCT values from both devices in standard care and clinical trials for DME.

Interleukin-18 system plays an important role in keloid pathogenesis via epithelial-mesenchymal interactions.

BACKGROUND: Keloid scarring is a dermal fibroproliferative disorder characterized by increased fibroblast proliferation and excessive production of collagen and extracellular matrix (ECM) components. To date, the role of cytokines in keloid pathogenesis has not been completely unravelled. Interleukin (IL)-18 is a pro-inflammatory cytokine that plays important roles in wound healing, fibrogenesis and carcinogenesis. OBJECTIVES: Our aim was to study the role of the IL-18 system in keloid pathogenesis. MATERIALS AND METHODS: Expression and localization of IL-18 and its receptor (IL-18R) were investigated in normal skin and keloid tissues using Western blot and immunohistochemistry. We further studied the expression of the IL-18 system in normal and keloid-derived cell lines in a coculture model. RESULTS: Results from Western blot and immunohistochemistry revealed that IL-18, IL-18Rα and IL-18Rß expression was elevated in keloid tissue compared with normal skin tissue. Studies on the expression of IL-18 and its antagonist, IL-18 binding protein (IL-18BP), using a coculture model demonstrated severe IL-18/IL-18BP imbalance in keloid keratinocyte/keloid fibroblast (KK/KF) cocultures with significant elevation of bioactive IL-18 whereas IL-18BP levels remained the same. This overproduction of bioactive IL-18 in keloid cocultures could be due to increased caspase-1 and decreased caspase-3 expression in keloid tissue, as well as decreased soluble IL-10 levels observed in keloid cocultures. The important inductive effects of IL-18 on KFs were further underscored by the observation that exposure of KF to IL-18 resulted in increased collagen and ECM component synthesis, and increased secretion of profibrotic cytokines such as IL-6 and IL-8. Finally, the addition of phosphatidylinositol 3-kinase (PI3K), mitogen activation protein kinase (MAPK), specificity protein 1 (Sp1) and mammalian target of rapamycin (mTOR) inhibitors inhibited IL-18 secretion in keloid cocultures. CONCLUSIONS: The present study has proven that the IL-18 system plays an important role in keloid pathogenesis via epithelial-mesenchymal interactions. It also suggests a therapeutic potential of PI3K, MAPK, Sp1 and mTOR inhibitors in the treatment of keloid scarring.

The role of stem cell factor and c-KIT in keloid pathogenesis: do tyrosine kinase inhibitors have a potential therapeutic role?

BACKGROUND: Keloids are fibroproliferative disorders characterized by increased deposition of extracellular matrix components. Stem cell factor (SCF) and its receptor c-KIT are expressed in a wide variety of cells and have also been demonstrated to be important modulators of the wound healing process. OBJECTIVES: To examine the role of the SCF/c-KIT system in keloid pathogenesis. METHODS: Immunohistochemical staining and Western blot analyses were used to examine localization and expression of SCF and c-KIT in keloid and normal skin tissue. This was followed by the detection of SCF and c-KIT expression in fibroblasts cultured in vitro and fibroblasts exposed to serum. To investigate the effect of epithelial-mesenchymal interactions, a two-chamber system was employed in which keratinocytes on membrane inserts were cocultured with the fibroblasts. SCF and c-KIT expression levels in all cell extracts and conditioned media were assayed by Western blotting. In another set of experiments, the effect of imatinib (Glivec(®), Gleevec(®); Novartis Pharma AG, Basel, Switzerland) on keloid fibroblasts was examined. RESULTS: SCF and c-KIT were upregulated in keloid scar tissue and in cultured fibroblasts stimulated with serum, highlighting their importance in the initial phase of wound healing. We further demonstrated that epithelial-mesenchymal interactions, mimicked by coculture of keratinocytes and fibroblasts in vitro, not only stimulated secretion of the soluble form of SCF in keloid cocultures but also brought about shedding of the extracellular domain of c-KIT perhaps by upregulation of tumour necrosis factor-α converting enzyme which was also upregulated in keloid scars in vivo and keloid cocultures in vitro. In addition keloid cocultures expressed increased levels of phosphorylated c-KIT highlighting an activation of the SCF/c-KIT system. Finally, we demonstrated that imatinib, a tyrosine kinase inhibitor, may be a possible therapeutic agent for keloids. CONCLUSION: These data indicate that the SCF/c-KIT system plays an important role in scar pathogenesis, and underscore the role of imatinib as a key therapeutic agent in keloid scars.

Comparative proteomic analysis between normal skin and keloid scar.

BACKGROUND: Keloids are pathological scars and, despite numerous available treatment modalities, continue to plague physicians and patients. OBJECTIVES: Identification of molecular mediators that contribute to this fibrotic phenotype. METHODS: Two-dimensional gel electrophoresis, MALDI-TOF, Mascot online database searching algorithm and Melanie 5 gel analysis software were employed for comparative proteomic analysis between normal skin (NS) and keloid scar (KS) tissue extracts. RESULTS: Seventy-nine protein spots corresponding to 23 and 32 differentially expressed proteins were identified in NS and KS, respectively. Isoforms of heat shock proteins, gelsolin, carbonic anhydrase and notably keratin 10 were strongly expressed in NS along with manganese superoxide dismutase, immune components, antitrypsin, prostatic binding protein and crystalline. Various classes of proteins were found either to be present or to be upregulated in keloid tissue: (i) inflammatory/differentiated keratinocyte markers: S100 proteins, peroxiredoxin I; (ii) wound healing proteins: gelsolin-like capping protein; (iii) fibrogenetic proteins: mast cell ß-tryptase, macrophage migration inhibitory factor (MIF); (iv) antifibrotic proteins: asporin; (v) tumour suppressor proteins: stratifin, galectin-1, maspin; and (vi) antiangiogenic proteins: pigment epithelium-derived factor. Significant increases in expression of asporin, stratifin, galectin-1 and MIF were observed by Western blot analysis in KS. CONCLUSIONS: This work has identified differentially expressed proteins specific to KS tissue extracts which can potentially be used as specific targets for therapeutic intervention.

Hepatoma-derived growth factor and its role in keloid pathogenesis.

Hepatoma-derived growth factor (HDGF) is a novel mitogenic growth factor that has been implicated in many different carcinomas. Its role in keloid biology has not yet been investigated. The present study is aimed at examining the role of HDGF in keloid pathogenesis. Immunohistochemical staining and Western blot analyses were used to examine in vivo localization and expression of HDGF in keloid and normal skin tissue. This was followed by the detection of HDGF expression in fibroblasts cultured in vitro and fibroblasts exposed to serum. To investigate the effect of epithelial-mesenchymal interactions, a two-chamber system was employed in which keratinocytes on membrane inserts were co-cultured with the fibroblasts. HDGF expression levels in all cell extracts and conditioned media were assayed through Western blot analysis. In another set of experiments, the effect of exogenous recombinant HDGF on keloid fibroblasts (KF) and normal fibroblasts (NF) was examined. Cell proliferation was assessed by the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay and by quantifying proliferating cell nuclear antigen (PCNA) expression. Downstream targets of HDGF were identified by detecting their expression through Western blot analysis. Our results indicate that there was an increase in HDGF expression in the dermis of keloid compared with normal skin tissue. The application of serum and epithelial-mesenchymal interactions did not seem to have any effect on intracellular HDGF expression levels. However, co-culturing keloid keratinocytes with KFs resulted in increased HDGF secretion when compared with monoculture or normal controls. Furthermore, treatment with exogenous recombinant HDGF was found to increase the proliferation of KFs, activate the extracellular signal-regulated kinase (ERK) pathway and up-regulate the secretion of vascular endothelial growth factor (VEGF).

An exploratory study of the safety, tolerability and bioactivity of a single intravitreal injection of vascular endothelial growth factor Trap-Eye in patients with diabetic macular oedema.

AIM: The aim of the study was to assess the safety and bioactivity of a single intravitreal injection of vascular endothelial growth factor (VEGF) Trap-Eye in subjects with diabetic macular oedema (DMO). METHODS: Five subjects with DMO, foveal thickness > or =250 microm measured by optical coherence tomography (OCT), and best-corrected visual acuity (BCVA) between 20/40 and 20/320, were enrolled. Each participant received a single intravitreal injection of 4.0 mg of VEGF Trap-Eye followed by a 6-week observation period. Outcome measures included safety and biological activity, including changes in BCVA and excess retinal thickness assessed by OCT. RESULTS: Injections of VEGF Trap-Eye were well tolerated with no ocular toxicity. One patient had an unrelated serious adverse event: hospitalisation for cellulitis of the left foot 27 days after injection of VEGF Trap-Eye. Median baseline BCVA was 36 ETDRS letters read at 4 m (not ETDRS visual acuity score; Snellen equivalent: 20/50) and median baseline excess central 1 mm foveal thickness (FTH) was 108 microm. At 4 weeks after injection, the median excess FTH was 59 microm and the median improvement in BCVA was nine letters. At 6 weeks after injection, four of the five patients showed improvement in excess FTH (median 74 microm; 31% reduction from baseline, p = 0.0625) and four of the five showed improvement in BCVA (median improvement of three letters). CONCLUSIONS: A single intravitreal injection of 4.0 mg of VEGF Trap-Eye was well tolerated and preliminary evidence of bioactivity was detected. These findings support additional studies investigating multiple injections of VEGF Trap-Eye in patients with DMO.

The incidence of endophthalmitis following transconjunctival sutureless 25- vs 20-gauge vitrectomy.

AIM: To determine the incidence of endophthalmitis following 25-gauge and standard 20-gauge vitrectomy. METHODS: In this single-centre retrospective interventional case series, we evaluated the incidence of acute endophthalmitis occurring within the 14-day postoperative period in all patients who underwent pars plana vitrectomy between 1 November 2002 and 31 December 2006. A total of 3477 consecutive patients were identified. Of them, 3046 patients underwent 20-gauge vitrectomy and 431 underwent 25-gauge vitrectomy. RESULTS: The event rates of postoperative endophthalmitis were 0.03% (1 of 3046) after 20-gauge vitrectomy and 0.23% (1 of 431) after 25-gauge vitrectomy (P=0.23). In the endophthalmitis case that occurred after 25-gauge vitrectomy, a combined phacoemulsification cataract surgery was performed with the 25-gauge vitrectomy. Analyses of event rates of postoperative endophthalmitis after combining phacoemulsification cataract surgery and vitrectomy were 0% (0 of 170) for 20-gauge vitrectomy and 2.17% (1 of 46) for 25-gauge surgery vitrectomy (P=0.21). CONCLUSION: The incidence of postoperative endophthalmitis following 25-gauge vitrectomy and 20-gauge surgery is low. Although there is a trend suggesting an increased risk of endophthalmitis with the 25-gauge system, this difference was not statistically significant given the low number of measured outcomes.

Common ophthalmic emergencies.

Ophthalmic emergencies are immediate threats to the visual system that can lead to permanent loss of visual function if left untreated. These emergencies should be detected by physicians and immediately treated and referred to an ophthalmologist if necessary. This article reviews the most common ophthalmic emergency room presentations, the history and physical examination for an ophthalmic emergency, and the diagnosis and management of each condition.

mTOR as a potential therapeutic target for treatment of keloids and excessive scars.

Keloid is a dermal fibroproliferative disorder characterized by excessive deposition of extracellular matrix (ECM) components such as collagen, glycoproteins and fibronectin. The mammalian target of rapamycin (mTOR) is a serine/theronine kinase which plays an important role in the regulation of metabolic processes and translation rates. Published reports have shown mTOR as regulator of collagen expression and its inhibition induces a decrease in ECM deposition. Our aim was to investigate the role of mTOR in keloid pathogenesis and investigate the effect of rapamycin on proliferating cell nuclear antigen (PCNA), cyclin D1, collagen, fibronectin and alpha-smooth muscle actin (alpha-SMA) expression in normal fibroblasts (NF) and keloid fibroblasts (KF). Tissue extracts obtained from keloid scar demonstrated elevated expression of mTOR, p70KDa S6 kinase (p70S6K) and their activated forms, suggesting an activated state in keloid scars. Serum stimulation highlighted the heightened responsiveness of KF to mitogens and the importance of mTOR and p70S6K during early phase of wound healing. Application of rapamycin to monoculture NF and KF, dose- and time-dependently downregulates the expression of cytoplasmic PCNA, cyclin D1, fibronectin, collagen and alpha-SMA, demonstrating the anti-proliferative effect and therapeutic potential of rapamycin in the treatment of keloid scars. The inhibitory effect of rapamycin was found to be reversible following recovery in the expression of proteins following the removal of rapamycin from the culture media. These results demonstrate the important role of mTOR in the regulation of cell cycle and the expression of ECM proteins: fibronectin, collagen and alpha-SMA.

Ranibizumab for the treatment of neovascular AMD.

Age-related macular degeneration (AMD) is the leading cause of adult blindness among individuals aged 50 and older in the Western world, with the neovascular form of AMD responsible for the most severe and rapid visual loss. Although monotherapy with currently available treatments can slow the rate of loss of vision in eyes with neovascular AMD, they do not significantly improve vision. Vascular endothelial growth factor-A (VEGF-A) plays a critical role in the pathogenesis of neovascular AMD, and ranibizumab is a promising new treatment that targets all VEGF-A isoforms and their biologically active degradation products. Clinical trials have reported that ranibizumab treatment resulted in greater proportions of patients achieving a < 15 letter loss of visual acuity and improved vision at 12 and 24 months than control groups. The incidence of serious ocular and systemic adverse events was low in all ranibizumab trials to date. Currently, ranibizumab is the only treatment for neovascular AMD to demonstrate significant improvement in vision for many patients and represents a major advance in treating neovascular AMD.

Epithelial-mesenchymal interactions in keloid pathogenesis modulate vascular endothelial growth factor expression and secretion.

Vascular endothelial growth factor (VEGF) plays an important role in angiogenesis during the wound healing process. As epithelial-mesenchymal interactions have been shown to regulate a plethora of genes in wound healing, we hypothesized that these interactions might have a role in modulating VEGF expression and angiogenesis. A two chamber co-culture model was used, wherein normal and keloid keratinocytes and fibroblasts were physically separated by membrane inserts while allowing cytokine diffusion. Cell lysates obtained from keratinocytes co-cultured with fibroblasts demonstrated increased expression of VEGF. An enzyme-linked immunosorbent assay (ELISA) showed significant increase in VEGF expression in co-culture conditioned media compared with controls. Additionally, the conditioned medium from keloid keratinocyte and fibroblast co-cultures increased proliferation and formation of complex three-dimensional capillary-like structures in human umbilical vein endothelial cells, emphasising the importance of epithelial-mesenchymal interactions in the angiogenic process. Immunostaining of keloid tissue localized VEGF in the basal layer of the epidermis and also demonstrated higher blood vessel density than normal skin. Keloid tissue extract also demonstrated increased expression of VEGF compared with normal skin. It is likely that epidermal VEGF exerts significant paracrine control over the dynamics and expression profile of underlying dermal fibroblasts. Addition of the inhibitors WP631, mitoxantrone, and Rapamycin to keloid keratinocyte and fibroblast co-cultures, downregulated secreted VEGF expression in a dose-dependent manner, suggesting therapeutic potential for these compounds in the treatment of keloid scars.