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1.
Trop Biomed ; 39(1): 126-134, 2022 Mar 01.
Article in English | MEDLINE | ID: mdl-35507935

ABSTRACT

Coronavirus Disease 2019 (COVID-19) has been spreading like a wildfire everywhere in the globe. It has been challenging the global health care system ever since the end of 2019, with its virulence and pathogenicity. Recent studies have shown the association between ABO blood group, Rhesus blood type and susceptibility to COVID-19 infection. Various studies and few meta-analyses have been done and some might be inconsistent; therefore, this meta-analysis was done to assess the relationship between different ABO and Rhesus blood types on the susceptibility to COVID-19 infections. This meta-analysis assessed the odds ratio of COVID-19 infection of different ABO and Rhesus blood types. Subgroup analyses according to (1) age and gender matched; (2) different blood group antigens; (3) Rhesus positive and negative of each blood group were carried out. Publication bias and Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) were also done to assess the risk of bias in these publications. It was found that blood group A showed significant difference in odds ratio of COVID-19 infection (OR, 1.16; 95% CI, 1.08-1.24). Blood group AB showed significant difference in odds ratio when studies with lower QUADAS-2 score were removed. This means that populations with blood group A and AB are more likely to be infected with COVID-19. As there is a higher tendency that blood group A and AB to be infected with COVID- 19, precautious care should be taken by these populations.


Subject(s)
COVID-19 , ABO Blood-Group System , Humans , SARS-CoV-2
2.
Tropical Biomedicine ; : 126-134, 2022.
Article in English | WPRIM (Western Pacific) | ID: wpr-936419

ABSTRACT

@#Coronavirus Disease 2019 (COVID-19) has been spreading like a wildfire everywhere in the globe. It has been challenging the global health care system ever since the end of 2019, with its virulence and pathogenicity. Recent studies have shown the association between ABO blood group, Rhesus blood type and susceptibility to COVID-19 infection. Various studies and few meta-analyses have been done and some might be inconsistent; therefore, this meta-analysis was done to assess the relationship between different ABO and Rhesus blood types on the susceptibility to COVID-19 infections. This meta-analysis assessed the odds ratio of COVID-19 infection of different ABO and Rhesus blood types. Subgroup analyses according to (1) age and gender matched; (2) different blood group antigens; (3) Rhesus positive and negative of each blood group were carried out. Publication bias and Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) were also done to assess the risk of bias in these publications. It was found that blood group A showed significant difference in odds ratio of COVID-19 infection (OR, 1.16; 95% CI, 1.08-1.24). Blood group AB showed significant difference in odds ratio when studies with lower QUADAS-2 score were removed. This means that populations with blood group A and AB are more likely to be infected with COVID-19. As there is a higher tendency that blood group A and AB to be infected with COVID19, precautious care should be taken by these populations.

3.
Opt Express ; 19(13): 12664-72, 2011 Jun 20.
Article in English | MEDLINE | ID: mdl-21716509

ABSTRACT

We proposed and demonstrated a novel practical fiber Bragg grating (FBG) fabrication setup constructed with high performance linear stages, piezoelectric translation (PZT) stages, and a highly stable continuous wave laser. The FBG fabrication system enables writing of long FBGs by a continuous translate-and-write process and allows implementation of arbitrary chirp and apodization. A key innovation is that the local Bragg wavelength is controlled by a simple movement of the phase mask by a PZT in the direction perpendicular to its surface. The focus position of the two writing beams is not changed during the Bragg wavelength change, an intrinsic feature of the design, ensuring simplicity, robustness and stability. Apodization can be achieved by vibrating the phase mask in the direction parallel to its surface by a PZT. Phase steps can also be inserted in FBGs at any desired locations by stepping the same PZT. A long uniform FBG and a linearly chirped FBG are written to demonstrate the performance of the setup.


Subject(s)
Fiber Optic Technology/methods , Interferometry/methods , Refractometry/methods , Equipment Design , Fiber Optic Technology/instrumentation , Interferometry/instrumentation , Models, Theoretical , Refractometry/instrumentation
4.
Clin Ter ; 162(6): 517-9, 2011.
Article in English | MEDLINE | ID: mdl-22262320

ABSTRACT

OBJECTIVES: A cross-sectional study was undertaken to determine and compare the refractive status of premature children without retinopathy of prematurity (ROP) and full term children below the age of three years. MATERIALS AND METHODS: Seventy children were examined. One group comprised of 40 children born premature without ROP and another group consisted of 30 children born full term and normal. Refractive error was determined using the Mohindra technique. RESULTS: Children below the age of three years born premature without ROP were significantly less hyperopic compared to children born full term and normal (t = 3.76, p = 0.0003). Our results show that children born premature without ROP are emmetropic when compared to children born full term. CONCLUSION: It is appears that emmetropization does occur in children born premature and full term. RESULTS: Need to be written in a new paragraph and in italics


Subject(s)
Infant, Premature, Diseases/epidemiology , Refractive Errors/epidemiology , Child, Preschool , Humans , Infant, Newborn , Infant, Premature , Retinopathy of Prematurity/complications
5.
Opt Express ; 18(16): 17373-81, 2010 Aug 02.
Article in English | MEDLINE | ID: mdl-20721124

ABSTRACT

We have observed symmetrical sidebands in reflection from Bragg grating written in a silica suspended-core fiber, which are caused by longitudinal periodic refractive index modulation in the Ge-doped suspended-core fiber with a core diameter of approximately 1.3 microm. Our simulation shows that the effective refractive index of the guided mode varied by 0.023% along the fiber with a period of approximately 650 microm. The periodic index variation can lead to amplitude modulation of fiber Bragg gratings, which can be studied by observing the spectra of a fiber Bragg grating written in the Ge-doped core. In addition, we have also characterized the temperature and strain responses of the fiber Bragg gratings, and showed that both responses in the suspended-core fiber are 20 to 25% lower than that of a fiber Bragg grating written on a conventional fiber.


Subject(s)
Fiber Optic Technology/instrumentation , Optical Fibers , Refractometry/instrumentation , Silicon Dioxide , Transducers , Equipment Design , Light , Temperature
6.
9.
J Clin Child Psychol ; 30(4): 536-51, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11708241

ABSTRACT

Examined a conceptual model in which dual developmental pathways (behavioral and cognitive) are hypothesized to account for the relation among internalizing behavior problems, intelligence, and later scholastic achievement using a cross-sectional sample of 325 children. Classroom behavior and select aspects of cognitive functioning (vigilance, short-term memory) were hypothesized to mediate the relations among internalizing problems, IQ, and long-term scholastic achievement. Hierarchical tests applied to a nested series of models demonstrated that (a) individual differences in measured intelligence among children are associated with variations in classroom performance and cognitive functioning, (b) classroom performance and cognitive functioning make unique contributions to prediction of later achievement over and above the influence of intelligence, (c) anxious/depressive features are correlated but separable constructs, and (d) anxiety/depression and withdrawal contribute to prediction of classroom performance and cognitive functioning over and above the effects of intelligence. Classroom performance and cognitive functioning thus appear to mediate the effects of internalizing behaviors as well as intelligence. Particular attention to the presence and potential impact of social withdrawal on children's functioning, both alone and concomitant with anxiety/depression, appears warranted during the course of clinical evaluations owing to the strong continuity among these variables.


Subject(s)
Cognition , Educational Status , Intelligence , Internal-External Control , Social Adjustment , Adolescent , Child , Child Development , Female , Hawaii , Humans , Male , Models, Psychological , Sampling Studies , Schools
10.
Plant Cell ; 13(8): 1779-90, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11487692

ABSTRACT

Senescence is a sequence of biochemical and physiological events that constitute the final stage of development. The identification of genes that alter senescence has practical value and is helpful in revealing pathways that influence senescence. However, the genetic mechanisms of senescence are largely unknown. The leaf of the oresara9 (ore9) mutant of Arabidopsis exhibits increased longevity during age-dependent natural senescence by delaying the onset of various senescence symptoms. It also displays delayed senescence symptoms during hormone-modulated senescence. Map-based cloning of ORE9 identified a 693-amino acid polypeptide containing an F-box motif and 18 leucine-rich repeats. The F-box motif of ORE9 interacts with ASK1 (Arabidopsis Skp1-like 1), a component of the plant SCF complex. These results suggest that ORE9 functions to limit leaf longevity by removing, through ubiquitin-dependent proteolysis, target proteins that are required to delay the leaf senescence program in Arabidopsis.


Subject(s)
Arabidopsis Proteins , Arabidopsis/physiology , Carrier Proteins/physiology , Plant Leaves/physiology , Abscisic Acid/metabolism , Acetates/metabolism , Amino Acid Sequence , Arabidopsis/genetics , Base Sequence , Carrier Proteins/chemistry , Carrier Proteins/metabolism , Cyclopentanes/metabolism , DNA Primers , Ethylenes/metabolism , Genes, Plant , Molecular Sequence Data , Mutation , Oxylipins , Plant Proteins/metabolism , Sequence Homology, Amino Acid
11.
Brain Res Bull ; 54(5): 537-42, 2001 Mar 15.
Article in English | MEDLINE | ID: mdl-11397545

ABSTRACT

The aim of the present study is to characterize the roles of spinal cholera toxin (CTX)- and pertussis toxin (PTX)-sensitive G proteins in the regulation of various nociceptive responses. The effects of intrathecal (i.t.) pretreatments with CTX and PTX on the formalin (subcutaneous)-, capsaicin (i.t.)-, and substance P (SP; i.t.)-induced nociceptive behaviours were examined in mice. Pretreatment with CTX (i.t.; 24 h before) significantly and dose-dependently (0.05-0.5 microg) suppressed both the first and second phases of the formalin-induced nociceptive behaviour. On the other hand, pretreatment with PTX (i.t., 6 days before) at the same doses (0.05-N0.5 microg) did not affect the formalin-induced response. Capsaicin (i.t., 0.5 microg)- and SP (i.t., 0.7 microg)-induced nociceptive behaviours were attenuated by the pretreatment with CTX. In addition, SP-induced nociceptive response was also attenuated by the pretreatment with PTX. However, the capsaicin-induced nociceptive response was not influenced by PTX pretreatment. These findings suggest that, at the spinal cord level, CTX-sensitive G-proteins are involved in the formalin-, capsaicin-, and SP-induced nociceptive behavioural responses, whereas PTX-sensitive G proteins are involved in SP-induced nociceptive response.


Subject(s)
Cholera Toxin/pharmacology , GTP-Binding Proteins/drug effects , Neurons/drug effects , Nociceptors/drug effects , Pain/metabolism , Pertussis Toxin , Spinal Cord/drug effects , Virulence Factors, Bordetella/pharmacology , Animals , Behavior, Animal/drug effects , Behavior, Animal/physiology , Capsaicin/pharmacology , Dose-Response Relationship, Drug , Drug Interactions/physiology , Formaldehyde/pharmacology , GTP-Binding Proteins/metabolism , Injections, Spinal , Male , Mice , Mice, Inbred ICR , Neurons/metabolism , Nociceptors/metabolism , Pain/chemically induced , Pain/physiopathology , Pain Measurement/drug effects , Pain Threshold/drug effects , Pain Threshold/physiology , Spinal Cord/metabolism , Substance P/pharmacology , Synaptic Transmission/drug effects , Synaptic Transmission/physiology
12.
J Clin Child Psychol ; 30(1): 48-58, 2001 Mar.
Article in English | MEDLINE | ID: mdl-11294077

ABSTRACT

Highlights the desirability of using a theoretical framework for guiding the design and evaluation of therapeutic interventions for children with attention deficit hyperactivity disorder (ADHD). A general conceptual model is introduced and used to evaluate ADHD treatment outcome research. Treatments designed to target the substrate level (pharmacological interventions) result in broad, robust improvement in both core and peripheral areas of functioning. Those targeting hypothesized core features of the disorder (i.e., attention, impulsivity-hyperactivity) produce corresponding improvement in core and peripheral outcome measures with the exception of studies employing cognitive-behavior therapy. Those targeting peripheral features of the disorder effect change only in corresponding peripheral areas of functioning. Implications for clinical practice are discussed, and an alternative conceptual model of ADHD is introduced and compared with existing models.


Subject(s)
Attention Deficit Disorder with Hyperactivity/psychology , Attention Deficit Disorder with Hyperactivity/therapy , Central Nervous System Stimulants/therapeutic use , Models, Psychological , Psychotherapy/methods , Attention , Behavior Therapy , Child , Cognitive Behavioral Therapy , Humans , Impulsive Behavior , Socialization
13.
Neuropeptides ; 35(5-6): 197-203, 2001.
Article in English | MEDLINE | ID: mdl-12030802

ABSTRACT

The present study was designed to examine the possible involvement of supraspinal CTX- and PTX-sensitive G-proteins in an opioid-induced antinociception in the formalin test. Morphine (1 microg) and beta-endorphin (1 microg) given i.c.v. displayed near-maximal inhibitory effects against the formalin response in the first (0-5 min) and the second (20-40 min) phases. CTX (0.1-0.5 microg) pretreated i.c.v. produced antinociceptive effects in both phases of the formalin responses. Its effect was more pronounced in the first phase. However, PTX (0.05-0.5 microg) injected i.c.v produced the antinociceptive effect only in the first, but not the second, phase. Both CTX (0.5 microg) and PTX (0.5 microg), at the dose which had no intrinsic effect, significantly reversed the beta-endorphin-induced antinociceptive effect observed during the second, but not the first, phase. However, the antinociceptive effect by morphine failed to be affected by the same dose of treatment with CTX or PTX. Our results indicate that, at the supraspinal level, CTX- and PTX-sensitive G-proteins appear to be involved in the modulation of antinociception induced by supraspinally administered beta-endorphin, but not morphine, in the formalin pain model.


Subject(s)
Brain/drug effects , Cholera Toxin/pharmacology , Morphine/pharmacology , Pain Measurement , Virulence Factors, Bordetella/pharmacology , beta-Endorphin/pharmacology , Analgesics, Opioid/pharmacology , Animals , Brain/metabolism , Formaldehyde/administration & dosage , GTP-Binding Proteins/metabolism , Male , Mice
14.
J Clin Child Psychol ; 29(4): 555-68, 2000 Dec.
Article in English | MEDLINE | ID: mdl-11126633

ABSTRACT

Reviews the usefulness of clinic-based and laboratory-based instruments and paradigms for diagnosing attention deficit hyperactivity disorder (ADHD) and monitoring treatment effects. Extant literature examining the performance of normal children and those with ADHD on an extensive range of neurocognitive tests, tasks, and experimental paradigms indicates that particular types of instruments may be more reliable than others with respect to detecting between-group differences. We review task parameters that may distinguish the more reliable from less reliable instruments. The value of clinic-based and laboratory-based instruments for monitoring treatment response in children with ADHD is questionable when evaluated in the context of ecologically relevant variables such as classroom behavior and academic functioning. We present a general conceptual model to highlight conceptual issues relevant to designing clinic-based and laboratory-based instruments for the purposes of diagnosing and monitoring treatment effects in children with ADHD. Application of the model to currently conceptualized core variables indicates that attention and impulsivity-hyperactivity may represent correlative rather than core features of the disorder. We discuss implications of these findings for designing the next generation of clinic-based and laboratory-based instruments.


Subject(s)
Attention Deficit Disorder with Hyperactivity/diagnosis , Child Behavior/classification , Child , Child Psychiatry/methods , Humans , Memory , Neuropsychological Tests , Observer Variation , Peer Group , Psychometrics , Task Performance and Analysis
15.
Neuropeptides ; 34(3-4): 158-66, 2000.
Article in English | MEDLINE | ID: mdl-11021975

ABSTRACT

Our previous studies have demonstrated that supraspinal glutamate receptors are differentially involved in the antinociception induced by morphine and beta-endorphin given intracerebroventricularly (i.c.v.) in the tail-flick and hot-plate tests. The formalin pain test was used in the present study. Injection of mice with formalin solution (2%, 10 microl) into the hindpaw intraplantarly produced the first (0-5 min) and second (20-40 min) phases of formalin responses. The formalin responses in the both phases were attenuated dose-dependently by morphine (0.125-1 microg) or beta-endorphin (0.125-1 microg) administered i.c.v. 5 min before. The antinociceptive effect of morphine was slightly more potent in the second phase whereas the effect of beta-endorphin was more pronounced in the first phase. MK-801 (0.1-1 microg), a non-competitive NMDA receptor antagonist, and CNQX (0.05-0.5 microg), a non-NMDA antagonist, given i.c.v., produced antinociceptive effect in the both phases, but only in a partial manner. Both MK-801 (0.05 microg) and CNQX (0.01 microg), at the dose which had no intrinsic effect, reversed the antinociceptive effect of beta-endorphin (1 microg) observed during the second, but not the first, phase partially but significantly. However, the antinociceptive effect of morphine (1 microg) was not affected by the same dose of MK-801 or CNQX given i.c.v. Our results indicate that, at the supraspinal level, both NMDA and non-NMDA receptors are involved in the production of antinociception induced by supraspinally administered beta-endorphin, but not morphine, in the formalin pain model.


Subject(s)
Analgesics/pharmacology , Morphine/pharmacology , Pain/physiopathology , Receptors, N-Methyl-D-Aspartate/physiology , beta-Endorphin/pharmacology , 6-Cyano-7-nitroquinoxaline-2,3-dione/administration & dosage , 6-Cyano-7-nitroquinoxaline-2,3-dione/pharmacology , Analgesics/administration & dosage , Animals , Brain/physiology , Cerebral Ventricles/drug effects , Cerebral Ventricles/physiology , Disease Models, Animal , Dizocilpine Maleate/administration & dosage , Dizocilpine Maleate/pharmacology , Excitatory Amino Acid Antagonists/administration & dosage , Excitatory Amino Acid Antagonists/pharmacology , Formaldehyde , Injections, Intraventricular , Male , Mice , Mice, Inbred ICR , Morphine/administration & dosage , Pain/chemically induced , Pain/drug therapy , Receptors, Glutamate/drug effects , Receptors, Glutamate/physiology , Receptors, N-Methyl-D-Aspartate/drug effects , Spinal Cord/physiology , beta-Endorphin/administration & dosage
16.
Brain Res ; 867(1-2): 246-9, 2000 Jun 09.
Article in English | MEDLINE | ID: mdl-10837821

ABSTRACT

The present study was designed to characterize the possible roles of spinally located cholera toxin (CTX)- and pertussis toxin (PTX)-sensitive G-proteins in excitatory amino acids induced pain response. Intrathecal (i.t.) injection of glutamate (20 microg), N-methyl-D-aspartic acid (NMDA; 60 ng), alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA; 13 ng), and kainic acid (12 ng) showed pain response. Pretreatment with CTX (0.05 and 0.5 microg, i.t.) attenuated pain response induced by glutamate, NMDA, AMPA and kainic acid administered i.t. in a dose-dependent manner. On the other hand, i.t. pretreatment with PTX further increased the pain response induced by glutamate, NMDA, AMPA and kainic acid administered i.t., especially at the dose of 0.5 microg. Our results suggest that, at the spinal cord level, CTX- and PTX-sensitive G-proteins appear to play opposite roles in modulating the pain response induced by spinally administered. Furthermore, CTX- and PTX-sensitive G-proteins appear to modulate pain response induced by stimuli of both NMDA and non-NMDA glutamate receptors.


Subject(s)
Adjuvants, Immunologic/pharmacology , Cholera Toxin/pharmacology , Pain/drug therapy , Pertussis Toxin , Virulence Factors, Bordetella/pharmacology , Animals , Excitatory Amino Acid Agonists/pharmacology , Injections, Spinal , Kainic Acid/pharmacology , Male , Mice , Mice, Inbred ICR , N-Methylaspartate/pharmacology , Pain/chemically induced , Spinal Cord/drug effects , Spinal Cord/physiology , alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid/pharmacology
17.
J Virol ; 74(11): 5233-41, 2000 Jun.
Article in English | MEDLINE | ID: mdl-10799599

ABSTRACT

It has been suggested that nonstructural protein 5A (NS5A) of hepatitis C virus (HCV) plays a role in the incapacitation of interferon by inactivation of RNA-dependent protein kinase PKR. In order to further investigate the role of NS5A, we tried to identify cellular proteins interacting with NS5A by using the yeast two-hybrid system. The karyopherin beta3 gene was isolated from a human liver cell library as a protein interacting with NS5A. The protein-protein interaction between NS5A and karyopherin beta3 was confirmed by in vitro binding assay and an in vivo coimmunoprecipitation method. The effect of NS5A on the karyopherin beta3 activity was investigated using a yeast cell line containing mutations in both PSE1 and KAP123, genes that are homologous to the human karyopherin beta3 gene. Human karyopherin beta3 complemented the loss of the PSE1 and KAP123 functions, supporting growth of the double mutant cells. However, expression of NS5A hampered the growth of the double mutant cells supplemented with human karyopherin beta3. On the other hand, expression of NS5A by itself had no effect on the growth of the double mutant expressing wild-type yeast PSE1. This indicates that NS5A may inhibit karyopherin beta3 function via protein-protein interaction. The role of NS5A in HCV replication is discussed.


Subject(s)
Membrane Transport Proteins , Nuclear Proteins/metabolism , Saccharomyces cerevisiae Proteins , Viral Nonstructural Proteins/physiology , Animals , Binding Sites , COS Cells , Genetic Complementation Test , Hepacivirus , Humans , Nuclear Proteins/genetics , Receptors, Cytoplasmic and Nuclear/genetics , Saccharomyces cerevisiae , Two-Hybrid System Techniques , Viral Nonstructural Proteins/genetics , Viral Nonstructural Proteins/metabolism , beta Karyopherins
18.
Arch Virol ; 144(2): 329-43, 1999.
Article in English | MEDLINE | ID: mdl-10470257

ABSTRACT

We determined the subcellular localization of hepatitis C viral (HCV) proteins as a first step towards the understanding of the functions of these proteins in the mammalian cell (CHO-K1). We used fluorescence emitted from green fluorescent protein (GFP)-fused to the viral proteins to determine the subcellular localization of the viral proteins. We found that most of the viral proteins were excluded from the nucleus. Core exhibited a globular pattern near the nucleus. NS2 was concentrated in the perinuclear space. NS4A accumulated in the ER and the Golgi regions. NS3 was detected in the nucleus as well as the cytoplasm, when it was expressed by itself. However, NS3 became restricted to the cytoplasm, when it was produced together with NS4A. NS4B showed a spot-like pattern throughout the cytoplasm. NS5A and NS5B were distributed throughout the cytoplasm in a mesh-like pattern. These results can provide a basis for further investigations into the functions of the HCV proteins.


Subject(s)
Hepacivirus/metabolism , Viral Proteins/analysis , Animals , CHO Cells , COS Cells , Cell Nucleus/metabolism , Cricetinae , Cytoplasm/metabolism , Gene Expression , Green Fluorescent Proteins , Hepacivirus/genetics , Luminescent Proteins/analysis , Luminescent Proteins/genetics , Microscopy, Fluorescence , Recombinant Fusion Proteins/analysis , Recombinant Fusion Proteins/genetics , Viral Nonstructural Proteins/analysis , Viral Nonstructural Proteins/genetics , Viral Proteins/genetics
19.
Plant Mol Biol ; 40(3): 419-29, 1999 Jun.
Article in English | MEDLINE | ID: mdl-10437826

ABSTRACT

APETALA1 (AP1) of Arabidopsis thaliana is a transcription factor controlling flower development. AP2 is a member of the MADS (MCM1, AGAMOUS, DEFICIENS, SRF) superfamily, which plays important roles in differentiation in plants and animals. MADS domains, which function most importantly in DNA binding, are found in all major eukaryotic kingdoms. In plants, MADS domain-containing proteins also possess a region of moderate sequence similarity named the K domain, which is involved in protein-protein interaction. Little is known about the function of a third, highly variable, domain designated the C domain, as it resides at the C terminus of the MADS proteins of plants. Here we report that the C-terminal domain of Arabidopsis thaliana AP1 and its homologues perform a transcriptional activation function. The C-terminal region of AP1 is composed of at least two separable transcriptional activation domains that function synergistically.


Subject(s)
Arabidopsis/genetics , Homeodomain Proteins/genetics , Plant Proteins/genetics , Transcription Factors/genetics , Amino Acid Sequence , Animals , Arabidopsis/metabolism , Arabidopsis Proteins , DNA-Binding Proteins/chemistry , DNA-Binding Proteins/genetics , DNA-Binding Proteins/metabolism , Genes, Homeobox , Genes, Plant , Homeodomain Proteins/chemistry , Homeodomain Proteins/metabolism , MADS Domain Proteins , Molecular Sequence Data , Plant Proteins/chemistry , Plant Proteins/metabolism , Plants/genetics , Sequence Homology, Amino Acid , Transcription Factors/chemistry , Transcription Factors/metabolism , Transcriptional Activation
20.
Optom Vis Sci ; 76(2): 121-6, 1999 Feb.
Article in English | MEDLINE | ID: mdl-10082059

ABSTRACT

The clinical significance of fundus magnification produced during direct ophthalmoscopy of the corrected eye has not been fully established. Based on paraxial ray tracing, fundus magnification (M) can be defined by a simple equation, M = (K'/4) x (Fs/K), where K' is the dioptric axial power of the eye, Fs is the correcting thin lens power and K is the ocular ametropia. Refractive myopes produce greater fundus magnification than axial myopes, whereas refractive hyperopes produce lower fundus magnification than axial hyperopes. If we assume 15 x fundus magnification as our standard magnification for an emmetropic reduced eye, then wearing glasses or putting the focusing lens at or close to the anterior focus of the eye is able to achieve the standard magnification for axial myope and axial hyperope, whereas wearing contact lenses is able to achieve the standard magnification for refractive myope and refractive hyperope. Vertex distance has greater influence on fundus magnification produced during direct ophthalmoscopy than other funduscopic techniques. In conclusion, the newly defined formula has clinical applications during direct ophthalmoscopy.


Subject(s)
Fundus Oculi , Ophthalmoscopy , Refractive Errors/pathology , Refractive Errors/therapy , Retina/pathology , Eyeglasses , Humans , Refraction, Ocular
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