Search results for "VISION"
showing 10 items of 5066 documents
Insulin-like growth factors in chick embryo retina during development.
1996
Evidence exists supporting an important role for insulin-like growth factors (IGFs) during fetal growth. In the present report we performed studies to define whether developing chick retina contains IGFs and whether IGFs play a role in the growth of this tissue. We have shown that both IGF-I and IGF-II are present in chick embryo retina throughout development (7th-18th day). The highest values, when expressed as ng/g of tissue, were found in the youngest retinas studied (7th-9th day) and at 16th-18th day of development. During whole development the content of IGF-II was about two to three times higher than that ascertained for IGF-I. The tissue also contains cell-surface binding for IGFs. H…
Development of a Protocol for CCD Calibration: Application to a Multispectral Imaging System
2005
In this paper we describe in detail a method for calibrating a CCD-based camera. The calibration aims to remove both temporal and systematic noises introduced by the sensor, electronics, and optics after which we can correct the non-linearity of its response. For the non-linearity correction we use a simple and powerful approach consisting on a complementary approach between a polynomial fitting and an LUT based algorithm. The proposed methodology is accurate in the sense that it takes into account individual characteristics of each pixel. In each pixel, systematic noises are measured through acquiring offset images, thermal images, and FlatField images. A rigorous protocol for acquiring th…
Ethanol inhibits astroglial cell proliferation by disruption of phospholipase D-mediated signaling.
2002
The activation of phospholipase D (PLD) is a common response to mitogenic stimuli in various cell types. As PLD-mediated signaling is known to be disrupted in the presence of ethanol, we tested whether PLD is involved in the ethanol-induced inhibition of cell proliferation in rat cortical primary astrocytes. Readdition of fetal calf serum (FCS) to serum-deprived astroglial cultures caused a rapid, threefold increase of PLD activity and a strong mitogenic response; both effects were dependent on tyrosine kinases but not on protein kinase C. Ethanol (0.1-2%) suppressed the FCS-induced, PLD-mediated formation of phosphatidic acid (PA) as well as astroglial cell proliferation in a concentration…
Editorial: CBCT special issue
2014
In the dental community, it is a common belief that CBCT was invented for oral and maxillofacial imaging. Of course, we know that this is a myth since the technique of a volumetric CT is indeed much older and dates back to the late 1970s.1,2 Considering that CT was introduced in 1973, its volumetric counterpart was developed very soon thereafter driven by the need for high spatial and temporal resolution that a conventional CT at that time was not able to achieve. However, successful marketing of the technique indeed was much later, and certainly a consequence of the publication of “A new volumetric CT machine for dental imaging based on the cone-beam technique: preliminary results” by Mozz…
Midregion parathyroid hormone-related protein inhibits growth and invasion in vitro and tumorigenesis in vivo of human breast cancer cells.
2001
Parathyroid hormone-related protein (PTHrP) is critical for normal mammary development and is overexpressed by breast cancers. PTHrP is a peptide hormone that undergoes extensive post-translational processing, and PTHrP(38–94)-amide is one of the mature secretory forms of the peptide. In this study, we explored the effect of PTHrP(38–94)-amide in a panel of six breast cancer cell lines “in vitro” and in MDA-MB231 cells “in vivo” specifically examining cell viability, proliferation, invasiveness, and growth in nude mice. PTHrP(38–94)-amide markedly inhibited proliferation and also caused striking toxicity and accelerated cell death in breast cancer cells. In addition, direct injection of PTH…
Cell Line and Growth Site as Relevant Parameters Governing Tumor Tissue Oxygenation
1986
Experimental rodent tumors commonly used in radiobiology exhibit a large inter-individual variability in the oxygenation status [1,2] and in the hypoxic cell fraction [3,4]. Paramount factors contributing to this variability may be tumor growth stage or tumor size [5], the cell line used, the growth site, the use of anaesthesia and certain tumor-host interactions (e.g. tumor-induced anemia). Concerning the basic pathogenetic mechanisms through which the above mentioned parameters can modulate tumor tissue oxygenation, variations of nutritive blood flow, inherent characteristics of the cell line (e.g. respiration rate or tumor growth rate), and finally changes in the O2 transport capacity of…
Ergebnisse nach Implantation einer Worst Iris Claw Lens zur Korrektur der hohen Myopie
2001
Fragestellung. Ziel dieser prospektiven klinischen Studie war die Erfassung der Refraktion, des korrigierten Visus und des Vorderkammerreizzustandes nach Implantation einer Worst Iris Claw Lens zur Korrektur der hohen Myopie. Patienten und Methode. Von Dezember 1996 bis Februar 1999 wurde bei insgesamt 44 phaken Augen von 28 Patienten eine Worst Iris Claw Lens implantiert. Es folgte eine Nachbeobachtungszeit von 6 Wochen bzw. 6 Monaten. Ergebnisse. Das mittlere praoperative spharische Aquivalent betrug −17,35±3,57 dpt. Sechs Monate postoperativ lag die Refraktion bei 79% der Augen im Intervall von ±1,0 dpt von der Zielrefraktion entfernt. Der mittlere korrigierte Visus stieg von praoperativ…
Changes in higher-order aberrations after implantation of a foldable iris-claw lens in myopic phakic eyes
2006
Purpose To evaluate the change in higher-order aberrations (HOAs) after implantation of a foldable iris-claw phakic intraocular lens (pIOL) in myopic eyes. Setting Department of Ophthalmology, Johannes Gutenberg-University, Mainz, Germany. Methods This prospective nonrandomized comparative self-controlled trial included 41 eyes that had implantation of a foldable iris-claw pIOL between July 2003 and November 2004. All patient data for HOAs (Zernike coefficient) were measured and calculated using the same pupil size preoperatively and postoperatively, and the root-mean-square (RMS) wavefront error was calculated. Examinations were performed preoperatively as well as 1 week and 3, 6, and 12 m…
Serous Macular Detachment Associated with Dome-Shaped Macula and Tilted Disc
2011
Introduction: An entirely new type of staphyloma has been recently described as dome-shaped macula (DSM). It is characterized by an abnormal convex macular contour within the concavity of a posterior staphyloma. We found DSM associated with serous macular detachment (SMD) and tilted disc in two consecutive cases. Case Reports: Case 1: A 37-year-old female presented to our department because of sudden onset blurred vision in her right eye (OD). The best-corrected visual acuity (BCVA) was 0.5 in both eyes. Funduscopy evidenced bilateral tilted disc associated with posterior staphyloma. Optical coherence tomography (OCT) demonstrated a DSM with SMD in her OD. After 15 months of follow-up, BCVA…
Multi-spectral skin imaging by a consumer photo-camera
2010
The possibilities to perform multi-band spectral imaging by means of a consumer color camera without external filters have been studied. Images at up to 6 spectral bands may be extracted from a single color image after appropriate signal processing. The proposed technique was tested in pilot measurements of in-vivo skin hemoglobin maps and laser-excited autofluorescence images.