相対的求心性瞳孔障害 relative afferent pupillary defect

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出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2015/07/06 03:38:45」(JST)

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RAPD (pronounced "rapid") stands for 'Random Amplified Polymorphic DNA'. It is a type of PCR reaction, but the segments of DNA that are amplified are random. The scientist performing RAPD creates several arbitrary, short primers (8–12 nucleotides), then proceeds with the PCR using a large template of genomic DNA, hoping that fragments will amplify. By resolving the resulting patterns, a semi-unique profile can be gleaned from a RAPD reaction.

No knowledge of the DNA sequence for the targeted genome is required, as the primers will bind somewhere in the sequence, but it is not certain exactly where. This makes the method popular for comparing the DNA of biological systems that have not had the attention of the scientific community, or in a system in which relatively few DNA sequences are compared (it is not suitable for forming a DNA databank). Because it relies on a large, intact DNA template sequence, it has some limitations in the use of degraded DNA samples. Its resolving power is much lower than targeted, species specific DNA comparison methods, such as short tandem repeats. In recent years, RAPD has been used to characterize, and trace, the phylogeny of diverse plant and animal species.

Introduction

RAPD markers are decamer (10 nucleotide length) DNA fragments from PCR amplification of random segments of genomic DNA with single primer of arbitrary nucleotide sequence and which are able to differentiate between genetically distinct individuals, although not necessarily in a reproducible way. It is used to analyse the genetic diversity of an individual by using random primers. Due to problems in experiment reproducibility, many scientific journals do not accept experiments merely based on RAPDs anymore. RAPD requires only one primer for amplification.

How it works

Unlike traditional PCR analysis, RAPD does not require any specific knowledge of the DNA sequence of the target organism: the identical 10-mer primers will or will not amplify a segment of DNA, depending on positions that are complementary to the primers' sequence. For example, no fragment is produced if primers annealed too far apart or 3' ends of the primers are not facing each other. Therefore, if a mutation has occurred in the template DNA at the site that was previously complementary to the primer, a PCR product will not be produced, resulting in a different pattern of amplified DNA segments on the gel.

Example

RAPD is an inexpensive yet powerful typing method for many bacterial species. The image visible at the link [1] is a silver-stained polyacrylamide gel showing three distinct RAPD profiles generated by primer OPE15 for Haemophilus ducreyi isolates from Tanzania, Senegal, Thailand, Europe, and North America.

Selecting the right sequence for the primer is very important because different sequences will produce different band patterns and possibly allow for a more specific recognition of individual strains.

Limitations of RAPD

Nearly all RAPD markers are dominant, i.e. it is not possible to distinguish whether a DNA segment is amplified from a locus that is heterozygous (1 copy) or homozygous (2 copies). Codominant RAPD markers, observed as different-sized DNA segments amplified from the same locus, are detected only rarely.
PCR is an enzymatic reaction, therefore the quality and concentration of template DNA, concentrations of PCR components, and the PCR cycling conditions may greatly influence the outcome. Thus, the RAPD technique is notoriously laboratory dependent and needs carefully developed laboratory protocols to be reproducible.
Mismatches between the primer and the template may result in the total absence of PCR product as well as in a merely decreased amount of the product. Thus, the RAPD results can be difficult to interpret.

Developing locus-specific, co-dominant markers from RAPDs

The polymorphic RAPD marker band is isolated from the gel.
It is amplified in the PCR reaction.
The PCR product is cloned and sequenced.
New longer and specific primers are designed for the DNA sequence, which is called the Sequenced Characterized Amplified Region Marker (SCAR).

External links

Rarphic DNA (RAPD). http://www.ncbi.nlm.nih.gov/projects/genome/probe/doc/TechRAPD.shtml
RAPD Technique at the US National Library of Medicine Medical Subject Headings (MeSH)

UpToDate Contents

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English Journal

Impact of dietary cadmium sulphide nanoparticles on Danio rerio zebrafish at very low contamination pressure.

Ladhar C1, Geffroy B, Cambier S, Treguer-Delapierre M, Durand E, Brèthes D, Bourdineaud JP.Author information 1University of Bordeaux, CNRS, UMR 5805, Arcachon Marine Station , Place du Dr Peyneau, 33120 Arcachon , France.AbstractTo address the impact of cadmium sulphide nanoparticles (CdSNPs) of two different sizes (8 and 50 nm), Danio rerio zebrafish were dietary exposed to very low doses: 100 or 40 ng CdSNPs/day/g body weight for 36 or 60 days, respectively. The results obtained using RAPD-PCR genotoxicity test showed genomic alteration since the number of hybridisation sites of the RAPD probes was significantly modified after CdSNPs exposure. In addition, selected stress response genes were either repressed or upregulated in tissues of CdSNPs-exposed fish. Mitochondrial dysfunction was also caused by the presence of CdSNPs in food. Cadmium accumulation in fish tissues (brain and muscles) could only be observed after 60 days of exposure. CdSNPs toxicity was dependent on their size and concentration.
Nanotoxicology.Nanotoxicology.2014 Sep;8(6):676-85. doi: 10.3109/17435390.2013.822116. Epub 2013 Jul 25.
To address the impact of cadmium sulphide nanoparticles (CdSNPs) of two different sizes (8 and 50 nm), Danio rerio zebrafish were dietary exposed to very low doses: 100 or 40 ng CdSNPs/day/g body weight for 36 or 60 days, respectively. The results obtained using RAPD-PCR genotoxicity test showed gen
PMID 23883150

Characterization of lactic acid bacteria isolated from infant faeces as potential probiotic starter cultures for fermented sausages.

Rubio R1, Jofré A, Martín B, Aymerich T, Garriga M.Author information 1IRTA-Food Safety Programme, Finca Camps i Armet, E-17121 Monells, Girona, Spain.AbstractA total of 109 lactic acid bacteria isolated from infant faeces were identified by partial 16S rRNA, cpn60 and/or pheS sequencing. Lactobacillus was the most prevalent genus, representing 48% of the isolates followed by Enterococcus (38%). Lactobacillus gasseri (21%) and Enterococcus faecalis (38%) were the main species detected. A further selection of potential probiotic starter cultures for fermented sausages focused on Lactobacillus as the most technologically relevant genus in this type of product. Lactobacilli strains were evaluated for their ability to grow in vitro in the processing conditions of fermented sausages and for their functional and safety properties, including antagonistic activity against foodborne pathogens, survival from gastrointestinal tract conditions (acidity, bile and pancreatin), tyramine production, antibiotic susceptibility and aggregation capacity. The best strains according to the results obtained were Lactobacillus casei/paracasei CTC1677, L. casei/paracasei CTC1678, Lactobacillus rhamnosus CTC1679, L. gasseri CTC1700, L. gasseri CTC1704, Lactobacillus fermentum CTC1693. Those strains were further assayed as starter cultures in model sausages. L. casei/paracasei CTC1677, L. casei/paracasei CTC1678 and L. rhamnosus CTC1679 were able to lead the fermentation and dominate (levels ca. 10(8) CFU/g) the endogenous lactic acid bacteria, confirming their suitability as probiotic starter cultures.
Food microbiology.Food Microbiol.2014 Apr;38:303-11. doi: 10.1016/j.fm.2013.07.015. Epub 2013 Aug 14.
A total of 109 lactic acid bacteria isolated from infant faeces were identified by partial 16S rRNA, cpn60 and/or pheS sequencing. Lactobacillus was the most prevalent genus, representing 48% of the isolates followed by Enterococcus (38%). Lactobacillus gasseri (21%) and Enterococcus faecalis (38%)
PMID 24290655

Cultivable microorganisms associated with honeys of different geographical and botanical origin.

Sinacori M1, Francesca N, Alfonzo A, Cruciata M, Sannino C, Settanni L, Moschetti G.Author information 1Department of Agricultural and Forestry Science, University of Palermo, Viale delle Scienze 4, 90128 Palermo, Italy.AbstractIn this study, the composition of the cultivable microbial populations of 38 nectar honey and honeydew honey samples of different botanical and geographical origin were assessed. After growth in specific media, various colonies with different appearance were isolated and purified before phenotypic (morphological, physiological and biochemical traits) and genotypic [randomly amplified polymorphic DNA (RAPD), repetitive DNA elements-PCR (rep-PCR) and restriction fragment length polymorphism (RFLP)] differentiation. The identification was carried out by 16S rRNA gene sequencing for bacteria and, in addition to RFLP, by sequencing the D1/D2 region of the 26S rRNA gene for yeasts and the 5.8S-ITS rRNA region for filamentous fungi. The results showed the presence of 13 species of bacteria, 5 of yeasts and 17 of filamentous fungi; the species most frequently isolated were Bacillus amyloliquefaciens, Zygosaccharomyces mellis and Aspergillus niger for the three microbial groups, respectively. The highest microbial diversity was found in multifloral honeys. No correlation among the microbial species and the botanical/geographical origin was found, but some strains were highly adapted to these matrices since they were found in several samples of different origin.
Food microbiology.Food Microbiol.2014 Apr;38:284-94. doi: 10.1016/j.fm.2013.07.013. Epub 2013 Aug 11.
In this study, the composition of the cultivable microbial populations of 38 nectar honey and honeydew honey samples of different botanical and geographical origin were assessed. After growth in specific media, various colonies with different appearance were isolated and purified before phenotypic (
PMID 24290653

Japanese Journal

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Phoung Pham Thi Minh,Isshiki Shiro,Miyajima Ikuo
Journal of the Faculty of Agriculture, Kyushu University 59(2), 235-241, 2014-08-29
… Results of floral observation and RAPD analysis indicate that there are four distinct groups of Hippeastrum being grown in Vietnam. … In the RAPD analysis result, 25 primers produced a total of 230 distinct bands, of which 167 were polymorphic (about 72.6%). … Our phylogeny indicated four separate groups, with dissimilarity values ranging from 0.2 to 0.3 according to the phylogeny based on RAPD results. …
NAID 120005472168

Phylogenetic Relationship of Hydrangea macrophylla (Thunb.) Ser. and H. serrata (Thunb.) Ser. Evaluated Using RAPD Markers and Plastid DNA Sequences

Uemachi Tatsuya,Mizuhara Yuri,Deguchi Kayoko [他]
Journal of the Japanese Society for Horticultural Science 83(2), 163-171, 2014-04
NAID 40020045641

虚血性視神経症の臨床的背景

春木崇宏,市邉義章,清水公也
あたらしい眼科 31(3), 449-452, 2014-03
NAID 40020035776

Related Pictures

Link para a aula de PCR da disciplina RAPD PCR RAPD Les marqueurs RAPD RAPD Reaction #2: RAPD

★リンクテーブル★

リンク元	「網膜中心動脈閉塞症」「交互点滅対光反射試験」「相対的求心性瞳孔障害」「relative afferent pupillary defect」
関連記事	「RA」「RAP」

「網膜中心動脈閉塞症」

　　[★]

英: central retinal artery occlusion
関: 網膜動脈閉塞症、網膜動脈分枝閉塞症

概念

網膜中心動脈の閉塞
眼科的には超緊急疾患

病因

参考1

頚動脈硬化
心原性塞栓症
小動脈疾患：糖尿病、高血圧
その他の血管疾患：頚動脈解離、線維筋異形成、頚動脈あるいは網膜動脈の放射線による損傷、もやもや病、ファブリー病
血液疾患：鎌状赤血球症、凝固亢進状態、白血病・リンパ腫
炎症疾患：血管炎を伴う自己免疫疾患(側頭動脈炎、Susac syndrome、その他(SLE、PAN、WG)

SOP.134

(1)血栓塞栓子、(2)乳頭内での粥状硬化、あるいは動脈炎による血管攣縮による動脈の閉塞、(3)緑内障や外力による高眼圧

症状

無痛性の高度視力障害
発症は急激

身体所見

RAPD陽性

検査

眼底検査：網膜は混濁、白濁。cherry-red spot(黄斑部は正常の赤色の色調を残し、それ以外の網膜は乳白色の混濁を認める)。

予後

1時間以内に血行が改善しないと網膜機能の回復は期待できない。
視力予後は不良

治療

眼球圧迫マッサージ
亜硝酸アミル
血栓溶解療法
(高眼圧の場合)前房穿刺
高圧酸素療法

参考

1. [charged] Central and branch retinal artery occlusion - uptodate [1]

「交互点滅対光反射試験」

　　[★]

英: swinging flashlight test
同: 交互対光反射試験
関: 相対的瞳孔求心路障害 relative afferent pupillary defect RAPD。マーカスガン瞳孔 Marcus Gunn pupil

検査方法：左右の眼に交互に光を当てる。
異常の判断：患側に光を入れても患側の瞳孔が収縮しない。

正常：光＞　・　　○

　　　　　　○　　・　＜光

異常：　　　　　(右眼)
　　　光＞　・　　○

　　　　　　○　　◎　＜光

　　　光＞　・　　○

異常が出るメカニズム：患側の直接反応は、健側の間接反応の方が弱い。そのため、健側から患側に光を当てると、患側の瞳孔が拡張する。
視神経障害(外傷性視神経障害、視神経炎、末期緑内障など)、広範な網膜障害(重度の網膜剥離)
異常がある場合、相対的求心路瞳孔反応異常あり(RAPD relative afferent papillary defect)という。

「相対的求心性瞳孔障害」

　　[★]

英: relative afferent pupillary defect, RAPD
同: 相対的瞳孔求心路障害
関: 対光反応、縮瞳異常、瞳孔不同(出力系の異常)。交互点滅対光反射試験

[show details]

相対的求心性瞳孔障害 : 32 件
相対的瞳孔求心路障害 : 25 件

相対的求心性瞳孔障害 RAPD : 20 件
相対的瞳孔求心路障害 RAPD : 14 件

入力系の異常、例えば視神経の異常を示唆する。
一方の眼に光を照射したときと、他方の眼に光を照射したときの縮瞳量に左右差がある場合にはRAPDがあるといい、誘発縮瞳量の小さい側の入力系に異常があることが考えられる。

「relative afferent pupillary defect」

　　[★] 相対的求心性瞳孔障害, RAPD

「RA」

　　[★]

「RAP」

　　[★]

匿名

検索

案内

案内

RAPD