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* PURPOSE: To compare the demographic and clinical distribution of primary and secondary congenital glaucoma from a registry at King Khaled Eye Specialist Hospital. * DESIGN: Registry-based cohort study. * METHODS: Review of registry data that included new patients with congenital glaucoma seen between 2001 and 2003 (29 months); analysis of the demographic data and clinical features of primary and secondary congenital glaucoma at presentation. * RESULTS: A total of 325 eyes of 180 patients were included. Most patients had primary congenital glaucoma (80%). The mean (± SD) age at presentation for primary congenital glaucoma was 3.8 ± 10.7 months and for secondary congenital glaucoma was 4.3 ± 7.9 months. Most primary congenital glaucoma and secondary congenital glaucoma patients had bilateral disease (82.6%; 74.3%). Primary congenital glaucoma was equally distributed by sex but secondary congenital glaucoma was 1.5-fold more common in male patients. A positive family history was elicited in 30%, and almost 60% had a history of consanguinity in both groups. The mean intraocular pressure and corneal diameter were comparable in both groups but the axial length was significantly longer in primary congenital glaucoma and cup-to-disc (C/D) ratio greater in secondary congenital glaucoma. In the primary congenital glaucoma group, corneal haze showed a significant relationship with most clinical parameters. In primary congenital glaucoma, a positive correlation was noted between age at presentation and increasing corneal diameter and axial length but a negative relationship was noted with C/D ratio and corneal haze, whereas for secondary congenital glaucoma only axial length was positively correlated. * CONCLUSION: The congenital glaucoma registry provides unique baseline data on primary congenital glaucoma and secondary congenital glaucoma in Saudi Arabia that will enable us to better understand the disease in the Kingdom and region. [ABSTRACT FROM AUTHOR]

Background: The ability to properly model intravascular steps in metastasis is essential in identifying key physical, cellular, and molecular determinants that can be targeted therapeutically to prevent metastatic disease. Research on the vascular microenvironment has been hindered by challenges in studying this compartment in metastasis under conditions that reproduce in vivo physiology while allowing facile experimental manipulation. Methodology/Principal Findings: We present a microfluidic vasculature system to model interactions between circulating breast cancer cells with microvascular endothelium at potential sites of metastasis. The microfluidic vasculature produces spatially-restricted stimulation from the basal side of the endothelium that models both organ-specific localization and polarization of chemokines and many other signaling molecules under variable flow conditions. We used this microfluidic system to produce site-specific stimulation of microvascular endothelium with CXCL12, a chemokine strongly implicated in metastasis. Conclusions/Significance: When added from the basal side, CXCL12 acts through receptor CXCR4 on endothelium to promote adhesion of circulating breast cancer cells, independent of CXCL12 receptors CXCR4 or CXCR7 on tumor cells. These studies suggest that targeting CXCL12-CXCR4 signaling in endothelium may limit metastases in breast and other cancers and highlight the unique capabilities of our microfluidic device to advance studies of the intravascular microenvironment in metastasis. [ABSTRACT FROM AUTHOR]

Endothelial cells (ECs) lining the inner lumen of blood vessels are continuously subjected to hemodynamic shear stress, which is known to modify EC morphology and biological activity. This paper describes a self-contained microcirculatory EC culture system that efficiently studies such effects of shear stress on EC alignment and elongation in vitro. The culture system is composed of elastomeric microfluidic cell shearing chambers interfaced with computer-controlled movement of piezoelectric pins on a refreshable Braille display. The flow rate is varied by design of channels that allow for movement of different volumes of fluid per variable-speed pump stroke. The integrated microfluidic valving and pumping system allowed primary EC seeding and differential shearing in multiple compartments to be performed on a single chip. The microfluidic flows caused ECs to align and elongate significantly in the direction of flow according to their exposed levels of shear stress. This microfluidic system overcomes the small flow rates and the inefficiencies of previously described microfluidic and macroscopic systems respectively to conveniently perform parallel studies of EC response to shear stress. [ABSTRACT FROM AUTHOR]

The results presented here identify a new RNA trafficking phenotype in taiep oligodendrocytes that increases the frequency of reversals and restricts the extent of transport of RNA containing the A2RE transport signal from MBP mRNA. The taiep rat is a myelin mutant characterized by excessive accumulation of microtubules in oligodendrocytes and myelin deficiency in the central nervous system. The taiep RNA trafficking is developmentally correlated with the microtubule accumulation in oligodendrocytes and can be partially suppressed by reducing microtubule density with nocodazole or inhibiting dynein activity by coinjecting anti-dynein antibodies. These results suggest that RNA trafficking in taiep oligodendrocytes is inhibited by enhanced dynein activity that neutralizes or lessens the normal overriding power of the plus-end directed motor kinesin. Altered orientation of microtubules in oligodendrocyte fine processes and a physical barrier created by densely packed microtubules may also contribute to the inhibition of RNA trafficking in taiep oligodendrocytes. [Copyright &y& Elsevier]

R3598 --> Inadequate oxygen delivery to tissue, or hypoxia, is caused by extensive abnormalities in the structure and function of the vascular network. Hypoxia also has a significant role in vascular diseases such as stroke, pregnancy disorders, and cancer. Despite its prevalence, there is no established method for alleviating hypoxia and its deleterious effects to vascular function. Existing experimental models are incapable of enabling cellular and intercellular microcirculatory measurements while also controlling the local oxygen environment, impeding our ability to mechanistically study these effects. Hemoglobin‐based oxygen carriers (HBOCs) are a promising class of red blood cell substitute which have been well characterized for transfusion medicine applications, yet little has been done to study the effects of HBOC administration on vascular function at the cellular level. In this work, we put forth a novel integration of microfluidic vascular models with HBOCs to investigate the effects of oxygen transport in microcirculation in vitro. We hypothesize that alleviating hypoxia with HBOCs restores normal blood vessel structure and function. We fabricated fully‐lumenized microvessels in vitro which mimic post‐capillary venules. We assessed vessel stability by immunofluorescence staining, and permeability under environmentally‐controlled normoxic and hypoxic conditions. We then synthesized polymerized hemoglobin (PolyHb), an HBOC with favorable molecular weight and oxygen‐carrying properties to alleviate hypoxia while minimizing extravasation and subsequent toxicity. We validated that PolyHb may be synthesized under varying conditions to selectively control the HBOC size and oxygen affinity, demonstrating that these properties can be modified to enable favorable oxygen transport and may be varied based on the desired application. As compared to previous generation HBOCs, PolyHb can attain molecular weights which will enable intravascular circulation to minimize toxicity, making PolyHb an ideal candidate for microfluidic investigation into the physiological effects of rescuing hypoxia. In future work, we will perfuse PolyHb through the engineered microvessels at constant flow and physiological shear stress levels to assess the ability of PolyHb to relieve induced hypoxia under imposed circumferential and longitudinally oriented hypoxia gradients. [ABSTRACT FROM AUTHOR]

The taiep mutant rat was first described in a colony of Sprague-Dawley rats at the University of Puebla in 1989, with an autosomal recessive inherited pattern. taiep is an acronym for the progressive neurologic deficits that the rat develops, i.e., t = trembling (3–4 weeks), a = ataxia (at 4 months), i = immobility (5–6 months), e = epilepsy (5–6 months), and p = paresis (7 months onwards). Thus, mutant rats are first identified by a tremor at 3–4 weeks of age that is followed by a progressive neurological worsening (Holmgren et al. 1989; Lunn et al. 1997). The cause of the neurological symptoms is an early failure of normal myelination of the central nervous system (CNS) followed by progressive demyelination of certain CNS tracts (Lunn et al. 1997). We have been exploring the underlying pathophysiology of the mutant and have determined that the myelin defect results from the progressive accumulation of microtubules in oligodendrocytes, the myelin-producing cells of the CNS (Song et al. 1999). Microtubules are the major component of the cytoskeleton of this and many other cells of the body, and microtubule-based transport of protein and mRNA is essential for normal cell function. There is no direct human counterpart of the taiep rat. Nonetheless, providing an understanding of the control of microtubule dynamics in the oligodendrocyte will be highly relevant to our knowledge of the cell biology of the myelinating cell of the CNS. This information is of great relevance to the function of the cell in human myelin disorders and in experimental remyelination. As the taiep rat apparently has a primary disorder in the oligodendrocyte cytoskeleton, it is an ideal model in which to study this process. This information may also be a key to the complete understanding of the mechanism of microtubule assembly/disassembly in many cell types. [ABSTRACT FROM AUTHOR]

With the advent of corneal refractive surgery using excimer laser technology, treatment for corneal and refractive disorders have advanced tremendously and become very precise and predictable. The use of these techniques in the treatment of corneal and refractive disorders in children, especially during the amblyogenic ages, would be invaluable. Numerous reports on refractive surgery in children have demonstrated that it can be performed safely and efficaciously in the pediatric population. However, controversy still exists whether it should be done in this population. We explore the available published data to address this controversy [ABSTRACT FROM AUTHOR]

Microfluidic systems have emerged as a new class of perfusable in vitro culture models that have helped advance and refine our understanding of microvascular function. Cutting-edge microfluidic models have successfully integrated principles from quantitative analysis of vascular function, in vitro flow chambers, microfabrication techniques, and 3D tissue scaffolds. Here, we review the evolution of microfluidic systems, namely their progression from 2D planar microchannel arrays to 3D microtissue analogs, and highlight their recent contributions in elucidating the role of biomolecular transport and fluid mechanical stimuli in controlling angiogenesis. Further advancement of microfluidic systems in recapitulating tissue-level phenomena in vitro, controlling important physiochemical and biological parameters, and integrating cellular and molecular analysis will help further enhance their application within the microcirculation research community. [ABSTRACT FROM AUTHOR]

Background: Molecular mechanisms underlying inflammation-associated breast tumor growth are poorly studied. S100A7, a pro-inflammatory molecule has been shown to enhance breast cancer growth and metastasis. However, the S100A7-mediated molecular mechanisms in enhancing tumor growth and metastasis are unclear. Methods: Human breast cancer tissue and plasma samples were used to analyze the expression of S100A7, cPLA2, and PGE2. S100A7-overexpressing or downregulated human metastatic breast cancer cells were used to evaluate the S100A7-mediated downstream signaling mechanisms. Bi-transgenic mS100a7a15 overexpression, TNBC C3 (1)/Tag transgenic, and humanized patient-derived xenograft mouse models and cPLA2 inhibitor (AACOCF3) were used to investigate the role of S100A7/cPLA2/PGE2 signaling in tumor growth and metastasis. Additionally, CODEX, a highly advanced multiplexed imaging was employed to delineate the effects of S100A7/cPLA2 inhibition on the recruitment of various immune cells. Results: In this study, we found that S100A7 and cPLA2 are highly expressed and correlate with decreased overall survival in breast cancer patients. Further mechanistic studies revealed that S100A7/RAGE signaling promotes the expression of cPLA2 to mediate its oncogenic effects. Pharmacological inhibition of cPLA2 suppressed S100A7-mediated tumor growth and metastasis in multiple pre-clinical models including transgenic and humanized patient-derived xenograft (PDX) mouse models. The attenuation of cPLA2 signaling reduced S100A7-mediated recruitment of immune-suppressive myeloid cells in the tumor microenvironment (TME). Interestingly, we discovered that the S100A7/cPLA2 axis enhances the immunosuppressive microenvironment by increasing prostaglandin E2 (PGE2). Furthermore, CO-Detection by indEXing (CODEX) imaging-based analyses revealed that cPLA2 inhibition increased the infiltration of activated and proliferating CD4+ and CD8+ T cells in the TME. In addition, CD163+ tumor associated-macrophages were positively associated with S100A7 and cPLA2 expression in malignant breast cancer patients. Conclusions: Our study provides new mechanistic insights on the cross-talk between S100A7/cPLA2 in enhancing breast tumor growth and metastasis by generating an immunosuppressive TME that inhibits the infiltration of cytotoxic T cells. Furthermore, our studies indicate that S100A7/cPLA2 could be used as novel prognostic marker and cPLA2 inhibitors as promising drugs against S100A7-overexpressing aggressive breast cancer. [ABSTRACT FROM AUTHOR]

Abstract: GL13NH2 is a bacteria-agglutinating peptide derived from the sequence of the salivary protein parotid secretory protein (PSP, BPIFA2, SPLUNC2, C20orf70). The peptide agglutinates both Gram negative and Gram positive bacteria, and shows anti-lipopolysaccharide activity in vitro and in vivo. However, GL13NH2 does not exhibit bactericidal activity. To generate a more cationic peptide with potential bactericidal activity, three amino acid residues were replaced with lysine residues to generate the peptide GL13K. In this report, the antibacterial and anti-inflammatory activities of GL13K were characterized. GL13K had lost the ability to agglutinate bacteria but gained bactericidal activity. Substitution of individual amino acids in GL13K with alanine did not restore bacterial agglutination. GL13K was bactericidal against Pseudomonas aeruginosa, Streptococcus gordonii and Escherichia coli but not Porphyromonas gingivalis. Unlike the agglutinating activity of GL13NH2, the bactericidal activity of GL13K against P. aeruginosa was retained in the presence of saliva. Both GL13NH2 and GL13K exhibited anti-lipopolysaccharide activity. In GL13K, this activity appeared to depend on a serine hydroxyl group. GL13K protected mice from lipopolysaccharide-induced sepsis and the peptide exhibited a low level of hemolysis, suggesting that it may be suitable for in vivo application. [Copyright &y& Elsevier]

The article discusses the study on the frequency, origin, and complications of acute and chronic pancreatitis in pregnancy and examines the risk factors of related outcomes. It presents a chart review of information on all pregnant patients with pancreatitis such as during presentation, management and outcome. It was found that cases of pancreatitis in pregnancy are rare, but often acute and linked to gallstone, and that pancreatitis of nonbiliary origin can be associated to worse conditions.

Evaporation is a critical problem when handling submicroliter volumes of fluids. This paper characterizes this problem as it applies to microfluidic cell culture in poly- (dimethylsioxane) (PDMS) devices and provides a practical solution. Evaporation-mediated osmolality shifts through PDMS membranes with varying thicknesses (10, 1, 0.2, or 0.1 mm) were measured over 96 h. Even in humidified cell culture incubators, evaporation through PDMS and associated shifts in the osmolality of culture media was significant and prevented mouse embryo and human endothelial cell growth and development. A simple diffusion model, where the measured diffusion coefficient for PDMS matches reported values of ~10-9 m²/s, accounts for these evaporation and osmolality shifts. To overcome this problem, a PDMS-parylene-PDMS hybrid membrane was developed that greatly suppresses evaporation and osmolality shifts, yet possesses thinness and the flexibility necessary to interface with deformation-based microfluidic actuation systems, maintains the clarity for optical microscopy, and enables the successful development of single-cell mouse embryos into blastocysts under static conditions and culture of human endothelial cells under dynamic recirculation of submicroliter volumes of media. These insights and methods demonstrated specifically for embryo and endothelial cell studies will be generally useful for understanding and overcoming evaporation-associated effects in microfluidic cell cultures. [ABSTRACT FROM AUTHOR]

Purpose: To report applications of optical coherence tomography (OCT) in the management of laser in situ keratomileusis (LASIK) related problems. Setting: Doheny Eye Institute and Department of Ophthalmology, Keck School of Medicine of the University of Southern California, Los Angeles, California, USA. Methods: Five patients referred for LASIK-related problems were enrolled in a prospective observational study. Clinical examination, ultrasound (US) pachymetry, Placido ring slit-scanning corneal topography (Orbscan II, Bausch & Lomb), and high-speed corneal OCT were performed. Results: In cases of regression and keratectasia, OCT provided thickness measurements of the cornea, flap, and posterior stromal bed. Locations of tissue loss and flap interface planes were identified in a case with a recut enhancement complication. The information was used to determine whether further laser ablation was safe, confirm keratectasia, and manage complications. Optical coherence tomography measurements of central corneal thickness agreed well with US pachymetry measurements (difference 6.4 μm ± 11.7 [SD]) (P = .026), while Orbscan significantly underestimated corneal thickness (−67.5 ± 72.5 μm) (P = .17). Conclusions: High-speed OCT provided noncontact imaging and measurement of LASIK anatomy. It was useful in monitoring LASIK results and evaluating complications. [Copyright &y& Elsevier]

Abstract: Two families of dogs (Australian cattle dogs and Shetland sheepdogs) with an inherited “spongiform leukoencephalomyelopathy” were identified, with widespread vacuolation of white matter of the brain and spinal cord. Affected dogs of both breeds developed tremors at 2–9 weeks of age followed by progressive neurological worsening with ataxia, paresis, paralysis, spasticity, and cranial nerve dysfunction. The modes of inheritance of both families were most likely maternal. The cerebrospinal fluid (CSF) analysis showed elevated ratio of 3-OH butyrate to acetoacetic acid. Mitochondrial DNA sequencing showed a G to A transition at 14,474 nt (G14474A, GenBank accession no. NC_002008) that results in an amino acid change of valine-98 to methionine (V98M) of mitochondrial encoded cytochrome b. Western blot analysis showed increased levels of core I and core II but decreased level of cytochrome c 1 of the complex III and cytochrome c oxidase of the complex IV of the respiratory chain. [Copyright &y& Elsevier]

Previous in vitro studies have reported on the use of direct current electric fields (DC-EFs) to regulate vascular endothelial permeability, which is important for tissue regeneration and wound healing. However, these studies have primarily used static 2D culture models that lack the fluid mechanical forces associated with blood flow experienced by endothelial cells (ECs) in vivo. Hence, the effect of DC-EF on ECs under physiologically relevant fluid forces is yet to be systematically evaluated. Using a 3D microfluidic model of a bifurcating vessel, we report the role of DC-EF on regulating endothelial permeability when co-applied with physiologically relevant fluid forces that arise at the vessel bifurcation. The application of a 70 V m−1 DC-EF simultaneously with 1 μL min−1 low perfusion rate (generating 3.8 dyn cm−2 stagnation pressure at the bifurcation point and 0.3 dyn cm−2 laminar shear stress in the branched vessel) increased the endothelial permeability 7-fold compared to the static control condition (i.e., without flow and DC-EF). When the perfusion rate was increased to 10 μL min−1 (generating 38 dyn cm−2 stagnation pressure at the bifurcation point and 3 dyn cm−2 laminar shear stress in the branched vessel) while maintaining the same electrical stimulation, a 4-fold increase in endothelial permeability compared to the static control was observed. The lower increase in endothelial permeability for the higher fluid forces but the same DC-EF suggests a competing role between fluid forces and the applied DC-EF. Moreover, the observed increase in endothelial permeability due to combined DC-EF and flow was transient and dependent on the Akt signalling pathway. Collectively, these findings provide significant new insights into how the endothelium serves as an electro-mechanical interface for regulating vessel permeability. [ABSTRACT FROM AUTHOR]

To understand how the microvasculature grows and remodels, researchers require reproducible systems that emulate the function of living tissue. Innovative contributions toward fulfilling this important need have been made by engineered microvessels assembled in vitro with microfabrication techniques. Microfabricated vessels, commonly referred to as “vessels-on-a-chip,” are from a class of cell culture technologies that uniquely integrate microscale flow phenomena, tissue-level biomolecular transport, cell–cell interactions, and proper three-dimensional (3-D) extracellular matrix environments under well-defined culture conditions. Here, we discuss the enabling attributes of microfabricated vessels that make these models more physiological compared with established cell culture techniques and the potential of these models for advancing microvascular research. This review highlights the key features of microvascular transport and physiology, critically discusses the strengths and limitations of different microfabrication strategies for studying the microvasculature, and provides a perspective on current challenges and future opportunities for vessel-on-a-chip models. [ABSTRACT FROM AUTHOR]

Immense progress in microscale engineering technologies has significantly expanded the capabilities of in vitro cell culture systems for reconstituting physiological microenvironments that are mediated by biomolecular gradients, fluid transport, and mechanical forces. Here, we examine the innovative approaches based on microfabricated vessels for studying lymphatic biology. To help understand the necessary design requirements for microfluidic models, we first summarize lymphatic vessel structure and function. Next, we provide an overview of the molecular and biomechanical mediators of lymphatic vessel function. Then we discuss the past achievements and new opportunities for microfluidic culture models to a broad range of applications pertaining to lymphatic vessel physiology. We emphasize the unique attributes of microfluidic systems that enable the recapitulation of multiple physicochemical cues in vitro for studying lymphatic pathophysiology. Current challenges and future outlooks of microscale technology for studying lymphatics are also discussed. Collectively, we make the assertion that further progress in the development of microscale models will continue to enrich our mechanistic understanding of lymphatic biology and physiology to help realize the promise of the lymphatic vasculature as a therapeutic target for a broad spectrum of diseases. [ABSTRACT FROM AUTHOR]

Background: Genomic studies have revealed that multiple genes are mutated at varying frequency in endometrial cancer (EC); however, the relevance of many of these mutations is poorly understood. An EC-specific recurrent mutation in the MAX transcription factor p.His28Arg was recently discovered. We sought to assess the functional consequences of this hotspot mutation and determine its association with cancer-relevant phenotypes.Methods: MAX was sequenced in 509 endometrioid ECs, and associations between mutation status and clinicopathologic features were assessed. EC cell lines stably expressing MAXH28R were established and used for functional experiments. DNA binding was examined using electrophoretic mobility shift assays and chromatin immunoprecipitation. Transcriptional profiling was performed with microarrays. Murine flank (six to 11 mice per group) and intraperitoneal tumor models were used for in vivo studies. Vascularity of xenografts was assessed by MECA-32 immunohistochemistry. The paracrine pro-angiogenic nature of MAXH28R-expressing EC cells was tested using microfluidic HUVEC sprouting assays and VEGFA enzyme-linked immunosorbent assays. All statistical tests were two-sided.Results: Twenty-two of 509 tumors harbored mutations in MAX, including 12 tumors with the p.His28Arg mutation. Patients with a MAX mutation had statistically significantly reduced recurrence-free survival (hazard ratio = 4.00, 95% confidence interval = 1.15 to 13.91, P = .03). MAXH28R increased affinity for canonical E-box sequences, and MAXH28R-expressing EC cells dramatically altered transcriptional profiles. MAXH28R-derived xenografts statistically significantly increased vascular area compared with MAXWT and empty vector tumors (P = .003 and P = .008, respectively). MAXH28R-expressing EC cells secreted nearly double the levels of VEGFA compared with MAXWT cells (P = .03, .005, and .005 at 24, 48, and 72 hours, respectively), and conditioned media from MAXH28R cells increased sprouting when applied to HUVECs.Conclusion: These data highlight the importance of MAX mutations in EC and point to increased vascularity as one mechanism contributing to clinical aggressiveness of EC. [ABSTRACT FROM AUTHOR]

Endothelial barrier function is known to be regulated by a number of molecular mechanisms; however, the role of biomechanical signals associated with blood flow is comparatively less explored. Biomimetic microfluidic models comprised of vessel analogues that are lined with endothelial cells (ECs) have been developed to help answer several fundamental questions in endothelial mechanobiology. However, previously described microfluidic models have been primarily restricted to single straight or two parallel vessel analogues, which do not model the bifurcating vessel networks typically present in physiology. Therefore, the effects of hemodynamic stresses that arise due to bifurcating vessel geometries on ECs are not well understood. Here, we introduce and characterize a microfluidic model that mimics both the flow conditions and the endothelial/extracellular matrix (ECM) architecture of bifurcating blood vessels to systematically monitor changes in endothelial permeability mediated by the local flow dynamics at specific locations along the bifurcating vessel structure. We show that bifurcated fluid flow (BFF) that arises only at the base of a vessel bifurcation and is characterized by stagnation pressure of ∼38 dyn cm−2 and approximately zero shear stress induces significant decrease in EC permeability compared to the static control condition in a nitric oxide (NO)-dependent manner. Similarly, intravascular laminar shear stress (LSS) (3 dyn cm−2) oriented tangential to ECs located downstream of the vessel bifurcation also causes a significant decrease in permeability compared to the static control condition via the NO pathway. In contrast, co-application of transvascular flow (TVF) (∼1 μm s−1) with BFF and LSS rescues vessel permeability to the level of the static control condition, which suggests that TVF has a competing role against the stabilization effects of BFF and LSS. These findings introduce BFF at the base of vessel bifurcations as an important regulator of vessel permeability and suggest a mechanism by which local flow dynamics control vascular function in vivo. [ABSTRACT FROM AUTHOR]

The extracellular matrix (ECM) is critical for mammary ductal development and differentiation, but how mammary fibroblasts regulate ECM remodeling remains to be elucidated. Herein, we used a mouse genetic model to activate platelet derived growth factor receptor-alpha (PDGFRα) specifically in the stroma. Hyperactivation of PDGFRa in the mammary stroma severely hindered pubertal mammary ductal morphogenesis, but did not interrupt the lobuloalveolar differentiation program. Increased stromal PDGFRα signaling induced mammary fat pad fibrosis with a corresponding increase in interstitial hyaluronic acid (HA) and collagen deposition. Mammary fibroblasts with PDGFRa hyperactivation also decreased hydraulic permeability of a collagen substrate in an in vitromicrofluidic device assay, whichwasmitigated by inhibition of either PDGFRα or HA. Fibrosis seen in this model significantly increased the overall stiffness of the mammary gland as measured by atomic force microscopy. Further, mammary tumor cells injected orthotopically in the fat pads of mice with stromal activation of PDGFRα grew larger tumors compared to controls. Taken together, our data establish that aberrant stromal PDGFRα signaling disrupts ECM homeostasis during mammary gland development, resulting in increased mammary stiffness and increased potential for tumor growth. [ABSTRACT FROM AUTHOR]

Inhibition of the vascular endothelial growth factor (VEGF) pathway has failed to improve overall survival of patients with glioblastoma (GBM). We previously showed that angiopoietin-2 (Ang-2) overexpression compromised the benefit from anti-VEGF therapy in a preclinical GBM model. Here we investigated whether dual Ang-2/VEGF inhibition could overcome resistance to anti-VEGF treatment. We treated mice bearing orthotopic syngeneic (Gl261) GBMs or human (MGG8) GBMxenografts with antibodies inhibiting VEGF (B20), or Ang-2/VEGF (CrossMab, A2V).We examined the effects of treatment on the tumor vasculature, immune cell populations, tumor growth, and survival in both the Gl261 and MGG8 tumor models. We found that in the Gl261 model, which displays a highly abnormal tumor vasculature, A2V decreased vessel density, delayed tumor growth, and prolonged survival compared with B20. In the MGG8 model, which displays a low degree of vessel abnormality, A2V induced no significant changes in the tumor vasculature but still prolonged survival. In both the Gl261 and MGG8 models A2V reprogrammed protumor M2 macrophages toward the antitumor M1 phenotype. Our findings indicate that A2V may prolong survival in mice with GBM by reprogramming the tumor immune microenvironment and delaying tumor growth. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate a haptic-based simulator, MicroVisTouch™, as an assessment tool for capsulorhexis performance in cataract surgery. The study is a prospective, unmasked, nonrandomized dual academic institution study conducted at the Wilmer Eye Institute at Johns Hopkins Medical Center (Baltimore, MD, USA) and King Khaled Eye Specialist Hospital (Riyadh, Saudi Arabia). Methods: This prospective study evaluated capsulorhexis simulator performance in 78 ophthalmology residents in the US and Saudi Arabia in the first round of testing and 40 residents in a second round for follow-up. Results: Four variables (circularity, accuracy, fluency, and overall) were tested by the simulator and graded on a 0-100 scale. Circularity (42%), accuracy (55%), and fluency (3%) were compiled to give an overall score. Capsulorhexis performance was retested in the original cohort 6 months after baseline assessment. Average scores in all measured metrics demonstrated statistically significant improvement (except for circularity, which trended toward improvement) after baseline assessment. A reduction in standard deviation and improvement in process capability indices over the 6-month period was also observed. Conclusion: An interval objective improvement in capsulorhexis skill on a haptic-enabled cataract surgery simulator was associated with intervening operating room experience. Further work investigating the role of formalized simulator training programs requiring independent simulator use must be studied to determine its usefulness as an evaluation tool. [ABSTRACT FROM AUTHOR]

R4151 --> 570.1 --> The extracellular matrix (ECM) enveloping cells in living tissue is comprised of signaling and structural support molecules. The ECM is vital to maintenance of normal tissue as it controls cell signaling and is a semiporous barrier to interstitial fluid flow. Two important types of ECM molecules are fibrillar collagen (e.g. type I) and glycosaminoglycans (GAGs). In certain solid tumors, hyaluronic acid (HA) and chondroitin sulfate (CS) are two types of GAG molecules that are known to be unusually abundant. These GAGs are negatively charged with the propensity to imbibe aqueous fluid and promote tissue swelling. While many studies have described the effect each molecule has on shaping ECM properties, studies describing how the CS and HA interact with each other are much less common. This study uses an integrated approach to characterize the effects of HA and CS on fluid transport (hydraulic permeability), stiffness (indentation modulus), collagen polymerization kinetics (turbidity), and matrix microarchitecture (pore size and fiber radius). Utilizing a microfluidic approach to study hydraulic permeability observed that the addition of GAGs decreased convective fluid transport. Indenting the hydrogels with a macroscale indenter demonstrated no changes in stiffness when adding CS, while HA, and CS/HA increased hydrogel stiffness. Analysis of confocal reflectance microscopy images showed increases in both pore size and fiber radius with the addition of both GAG molecules. Finally, turbidity measurements concluded that adding GAGs to a collagen gel accelerated its polymerization, with the change in fiber radius being the primary determinant in enhanced fibril formation. This study provides additional evidence that GAGs play an important role in defining physical properties of the ECM and demonstrates further ways into controllably modifying collagen based hydrogels via the addition of native ECM molecules. [ABSTRACT FROM AUTHOR]

In this brief communication, we present the steps used to establish a web-based congenital glaucoma registry at our institution. The contents of a case report form (CRF) were developed by a group of glaucoma subspecialists. Information Technology (IT) specialists used Lime Survey softwareTM to create an electronic CRF. A MY Structured Query Language (MySQL) server was used as a database with a virtual machine operating system. Two ophthalmologists and 2 IT specialists worked for 7 hours, and a biostatistician and a data registrar worked for 24 hours each to establish the electronic CRF. Using the CRF which was transferred to the Lime survey tool, and the MYSQL server application, data could be directly stored in spreadsheet programs that included Microsoft Excel, SPSS, and R-Language and queried in real-time. In a pilot test, clinical data from 80 patients with congenital glaucoma were entered into the registry and successful descriptive analysis and data entry validation was performed. A web-based disease registry was established in a short period of time in a cost-efficient manner using available resources and a team-based approach. [ABSTRACT FROM AUTHOR]

Background: Genetic variation may contribute to differential gene expression in the brain of individuals with psychiatric disorders. To test this hypothesis, we identified genes that were differentially expressed in individuals with bipolar disorder, along with nearby single nucleotide polymorphisms (SNPs) that were associated with expression of the same genes. We then tested these SNPs for association with bipolar disorder in large case-control samples. Methods: We used the Stanley Genomics Database to extract gene expression and SNP microarray data from individuals with bipolar disorder (n = 40) and unaffected controls (n = 43). We identified 367 genes that were differentially expressed in the prefrontal cortex of cases vs. controls (fold change > 1.3 and FDR q-value < .05) and 45 nearby SNPs that were associated with expression of those same genes (FDR q-value < .05). We tested these SNPs for association with bipolar disorder in a meta-analysis of genome-wide association studies (GWAS) including 4,936 cases and 6,654 healthy controls. Results: We identified 45 SNPs that were associated with expression of differentially expressed genes, including HBS1L (15 SNPs), HLA-DPB1 (15 SNPs), AMFR (8 SNPs), PCLO (2 SNPs) and WDR41 (2 SNPs). Of these, one SNP (rs13438494), in an intron of the piccolo (PCLO) gene, was significantly associated with bipolar disorder (FDR adjusted p < .05) in the meta-analysis of GWAS. Conclusions: These results support the previous findings implicating PCLO in mood disorders and demonstrate the utility of combining gene expression and genetic variation data to improve our understanding of the genetic contribution to bipolar disorder. [ABSTRACT FROM AUTHOR]

Purpose: To study the architecture of clear corneal incisions for phacoemulsification cataract surgery using optical coherence tomography (OCT). Setting: Doheny Eye Institute and Department of Ophthalmology, Keck School of Medicine of the University of Southern California, Los Angeles, California, USA. Methods: This prospective study comprised 20 eyes of 20 patients 1 month after cataract surgery performed by 1 of 2 experienced surgeons. Temporal clear corneal single-plane incisions were made with 3.0 mm metal keratomes. Each eye was scanned before and 1 month after surgery with a prototype high-speed anterior segment OCT system (Carl Zeiss Meditec, Inc.). The OCT scans were repeated 3 times during the same visit. The length of the corneal incision, thickness of the cornea, and position of the incision (distance from external wound edge to scleral spur) were measured using a computer caliper. The angle of the incision relative to the corneal surface was then calculated. Results: The mean corneal incision length was 1.81 mm ± 0.27 (SD), the mean corneal thickness at the incision was 747 ± 67μm, and the mean distance between the incision and the scleral spur was 1.46 ± 0.24 mm. The mean angle of the incision was 26.8 ± 5.5 degrees. The measurements were repeatable to within ±0.072 mm (pooled standard deviation) for the incision length, ±11 μm for the corneal thickness, and ±0.042 mm for the position of the incision. Conclusions: Optical coherence tomography allowed excellent evaluation of corneal incisions in cataract surgery postoperatively. Measurements of wound dimensions using OCT were highly repeatable. [Copyright &y& Elsevier]

Abstract: Cell culture systems are often static and are therefore nonphysiological. In vivo, many cells are exposed to dynamic surroundings that stimulate cellular responses in a process known as mechanotransduction. To recreate this environment, stretchable cell culture substrate systems have been developed, however, these systems are limited by being macroscopic and low throughput. We have developed a device consisting of 24 miniature cell stretching chambers with flexible bottom membranes that are deformed using the computer-controlled, piezoelectrically actuated pins of a Braille display. We have also developed efficient image capture and analysis protocols to quantify morphological responses of the cells to applied strain. Human dermal microvascular endothelial cells (HDMECs) were found to show increasing degrees of alignment and elongation perpendicular to the radial strain in response to cyclic stretch at increasing frequencies of 0.2, 1, and 5Hz, after 2, 4, and 12h. Mouse myogenic C2C12 cells were also found to align in response to the stretch, while A549 human lung adenocarcinoma epithelial cells did not respond to stretch. [Copyright &y& Elsevier]

Purpose: To investigate intrastromal corneal ring segment depth with a high-speed corneal optical coherence tomography (OCT) system. Setting: Doheny Eye Institute, University of Southern California, Los Angeles, California, USA. Methods: A prospective observational case series comprised 4 eyes of 4 patients receiving Intacs intrastromal corneal ring segments (Addition Technology, Inc.) for keratoconus. Optical coherence tomography (OCT) was performed between 7 days and 43 days after implantation. Results: The slitlamp impression of intrastromal corneal ring segment implantation depth did not correlate well with OCT measurements (r 2 = 0.68). The fractional implantation depth was correlated with several surgical variables using a stepwise multivariate regression model, and 2 statistically significant correlations were found. The position of the distal portions of the ring segments was shallower than that of the portion closer to the insertion site (P = .003). Segments placed in the inferior cornea (P = .008) experienced more distal shallowing. Shallower depth was associated with greater fractional anterior stromal compression (P = .04). Conclusions: Shallower placement of intrastromal corneal ring segments may result in more complications, such as epithelial–stromal breakdown and extrusion, because of the greater anterior stromal tensile strain. The distal and inferior portions of intrastromal corneal ring segments tended to be placed at a shallower depth. Optical coherence tomography provided precise measurement of ring segment depth and may help identify implants that pose a greater risk for depth-related complications. [Copyright &y& Elsevier]

Interactions between cells and their environment influence key physiologic processes such as their propensity to migrate. However, directed migration controlled by extrinsically applied electrical signals is poorly understood. Using a novel microfluidic platform, we found that metastatic breast cancer cells sense and respond to the net direction of weak (∼100 µV cm−1), asymmetric, non-contact induced Electric Fields (iEFs). iEFs inhibited EGFR (Epidermal Growth Factor Receptor) activation, prevented formation of actin-rich filopodia, and hindered the motility of EGF-treated breast cancer cells. The directional effects of iEFs were nullified by inhibition of Akt phosphorylation. Moreover, iEFs in combination with Akt inhibitor reduced EGF-promoted motility below the level of untreated controls. These results represent a step towards isolating the coupling mechanism between cell motility and iEFs, provide valuable insights into how iEFs target multiple diverging cancer cell signaling mechanisms, and demonstrate that electrical signals are a fundamental regulator of cancer cell migration. Ayush Arpit Garg et al. demonstrate that metastatic breast cancer cells respond to weak, non-contact induced Electric Fields, reducing their motility in an Akt-dependent manner. This study provides insight into how non-contact induced Electric Fields regulate cancer cell signaling to hinder their migration. [ABSTRACT FROM AUTHOR]

Purpose: To determine whether systemic replacement with combined esterified estrogen (EE) and methyltestosterone (MT) (EE + MT) would reduce symptoms and promote clinical improvement in postmenopausal women with dry eye syndrome (DES). Design: Retrospective, noncomparative, interventional case series. Methods: Investigators reviewed the charts of 11 postmenopausal women treated within the last 3 years with EE + MT. Results: The mean patient age was 65.2 years (standard deviation [SD] 11.4, range 48–84 years). The mean treatment duration was 12.2 months (SD 6.2 months, range 4–24 months). Ten (91%) of 11 patients reported improvement in dry eye symptoms while receiving treatment. For these 10, relief occurred after an average of 4.1 months of treatment (SD 3.2, range, 1–9 months). Conclusions: Treatment with EE + MT may be efficacious for DES of various etiologies. A randomized placebo-controlled trial is planned to further evaluate these encouraging findings. [Copyright &y& Elsevier]

Purpose: To summarize the evolution of the treatment of pediatric refractive errors, with an emphasis on recent advancements in the use of refractive surgery to treat children. Design: Literature review. Methods: We searched MEDLINE (1950 through October 2007), the Cochrane library (December through October 2007), and the Cumulative Index for Nursing and Allied Health Literature (December 1982 through October 2007) for English language articles using the following search strategy with MeSH terms and key words: pediatric refractive errors and amblyopia, anisometropia, hyperopia, myopia, laser in situ keratomileusis (LASIK), photorefractive keratectomy (PRK), laser epithelial keratomileusis (LASEK), excimer laser, refractive intraocular lens (IOL). We also searched the bibliographies of all identified articles. Results: No multicenter, long-term, controlled trial has been published on the use of refractive surgery in children. The current literature shows that LASIK, PRK, and LASEK show promising results in children with refractive amblyopia over the intermediate follow-up period. Corneal haze and myopic regression are the main complications, especially in very high myopia (> 12 diopters). In such patients with extremely high myopia, small studies have reported phakic IOLs or clear lens extraction with or without IOL implantation to be a useful alternative. Conclusions: Refractive surgery is appropriate in children with severe anisometropia or bilateral high ametropia that is resistant to conventional therapy. More information is needed before pediatric refractive surgery can be widely adopted by the ophthalmic community. This could be achieved with a large, prospective, multicenter, randomized, controlled clinical trial. [Copyright &y& Elsevier]