Rashin jituwa
| Rashin jituwa | |
|---|---|
 | |
Description (en)  | |
| Iri |
learning disability (en) reading disability (en) |
| Field of study (en) |
neuropsychology (en) pediatrics (en) |
| Sanadi | ciwon kwayoyin halitta |
| Symptoms and signs (en) |
reading disorder and écrites disorder (en) |
| Physical examination (en) |
functional magnetic resonance imaging (en) |
| Genetic association (en) |
PCSK6 (en) |
| Identifier (en) | |
| ICD-10-CM | R48.0 |
| OMIM | 300509, 600202, 604254, 606616, 606896 da 608995 |
| DiseasesDB | 4016 |
| MedlinePlus | 001406 |
| eMedicine | 001406 |
| MeSH | D004410 |
| Disease Ontology ID | DOID:4428 |
Juyin halittar rigakafi wani nau'in bambancin kwayoyin halitta ne a cikin ƙwayoyin cuta, wanda ya samo asali ne daga tarin sauye- sauye a cikin kwayoyin halittar ƙwayoyin cuta waɗanda ke tsara sunadaran saman ƙwayoyin cuta waɗanda ke karɓar ƙwayoyin cuta . Wannan yana haifar da sabon nau'in ƙwayoyin cuta wanda ƙwayoyin rigakafi waɗanda suka hana kamuwa da cuta ta nau'ikan da suka gabata ba su hana shi yadda ya kamata ba. Wannan yana sauƙaƙa wa ƙwayar cutar da aka canza ta yaɗuwa a cikin jama'ar da ke da ɗan garkuwar jiki. Juyin halittar rigakafi yana faruwa a cikin ƙwayoyin cutar influenza A da influenza B
(Rikici na iya tasowa da kalmomi guda biyu masu kama da juna, canjin antigenic da kuma canjin kwayoyin halitta . Canjin antigenic tsari ne mai alaƙa da juna; yana nufin canje-canje masu ban mamaki a cikin sunadaran saman kwayar cutar lokacin da kayan kwayoyin halitta daga ƙwayoyin cuta biyu ko fiye suka haɗu. Canjin kwayoyin halitta ya bambanta sosai kuma ya fi dacewa; yana nufin tarin hankali a cikin kowane jerin DNA na canje-canjen maye gurbi bazuwar wanda ba ya tsoma baki ga aikin DNA kuma don haka waɗanda ba a gani ta hanyar zaɓin halitta ba.)
Tsarin garkuwar jiki yana gane ƙwayoyin cuta lokacin da antigens a saman barbashi na ƙwayar cuta suka haɗu da masu karɓar garkuwar jiki waɗanda suka keɓance ga waɗannan antigens. Waɗannan masu karɓar na iya zama ƙwayoyin rigakafi a cikin jini ko makamancin haka sunadaran furotin a saman ƙwayoyin garkuwar jiki. Wannan ganewar ta yi daidai, kamar maɓalli da ke gane kulle. Bayan kamuwa da cuta ko bayan allurar rigakafi, jiki yana samar da ƙarin waɗannan masu karɓar garkuwar jiki na ƙwayar cuta, waɗanda ke hana sake kamuwa da wannan nau'in ƙwayar cuta; wannan ana kiransa garkuwar jiki da aka samu . Duk da haka, kwayoyin halittar ƙwayoyin cuta suna canzawa koyaushe, suna samar da sabbin nau'ikan waɗannan antigens. Idan ɗaya daga cikin waɗannan sabbin nau'ikan antigen ya bambanta da tsohon antigen, ba zai sake ɗaurewa da ƙwayoyin rigakafi ko masu karɓar ƙwayoyin rigakafi ba, wanda ke ba da damar ƙwayar cuta mai canzawa ta kamu da mutanen da suka riga sun kamu da cutar saboda kamuwa da cuta ko allurar riga-kafi a baya.
A shekarun 1940, Maurice Hilleman ya gano sauye-sauyen antigenic, wanda shine hanyar da ƙwayoyin cuta na mura ke canzawa. [1] [2] [3] Nau'i na biyu na canji shine canjin antigenic, wanda Hilleman ya gano, [1] [2] inda kwayar cutar ke samun sabon sigar ɗaya daga cikin kwayoyin halittar furotin na samanta daga ƙwayar cutar mura mai nisa. Yawan sauye-sauyen antigenic ya dogara ne akan halaye biyu: tsawon lokacin annobar, da ƙarfin garkuwar jiki. Yaɗuwar annoba mai tsawo yana ba da damar matsin lamba na zaɓi ya ci gaba na tsawon lokaci kuma ƙarfin martanin garkuwar jiki mai ƙarfi yana ƙara matsin lamba na zaɓi don haɓaka sabbin ƙwayoyin cuta. [4]
A cikin ƙwayoyin cuta na mura
[gyara sashe | gyara masomin]A cikin kwayar cutar mura, antigens guda biyu masu mahimmanci sune sunadaran saman, hemagglutinin da neuraminidase . [5] Hemagglutinin yana da alhakin ɗaurewa da shiga cikin ƙwayoyin epithelial masu masaukin baki yayin da neuraminidase ke da hannu a cikin tsarin sabbin ƙwayoyin cuta da ke fitowa daga ƙwayoyin masu masaukin baki. [6] Wuraren da aka gane akan sunadaran hemagglutinin da neuraminidase ta hanyar tsarin garkuwar jiki na mai masaukin baki suna ƙarƙashin matsin lamba akai-akai. Rashin daidaituwar ƙwayoyin cuta yana ba da damar guje wa waɗannan tsarin garkuwar jiki ta hanyar ƙananan maye gurbi a cikin kwayoyin halittar hemagglutinin da neuraminidase waɗanda ke sa furotin ba za a iya gane shi zuwa ga garkuwar jiki da ke akwai ba. [7] Rashin daidaituwar ƙwayoyin cuta shine wannan ci gaba na canjin kwayoyin halitta da antigenic tsakanin nau'ikan mura. [8]
A cikin al'ummar ɗan adam, mutanen da aka yi wa allurar rigakafi (masu rigakafi) suna yin matsin lamba na zaɓi don maye gurbin maki ɗaya a cikin kwayar halittar hemagglutinin wanda ke ƙara sha'awar ɗaure mai karɓa, yayin da mutane marasa hankali ke yin matsin lamba na zaɓi don maye gurbin maki ɗaya wanda ke rage sha'awar ɗaure mai karɓa. [7] Waɗannan matsin lamba na zaɓi mai ƙarfi suna sauƙaƙa saurin juyin halitta a cikin kwayar halittar hemagglutinin. Musamman, an gano takamaiman codons 18 a cikin yankin HA1 na kwayar halittar hemagglutinin suna fuskantar zaɓi mai kyau don canza amino acid ɗinsu mai lamba. [9] Don magance ƙalubalen karkatar da antigenic, ana buƙatar alluran rigakafi waɗanda ke ba da kariya mai yawa daga nau'ikan heterovariant akan yanayi, annoba da mura ta annoba. [10]
Kamar yadda yake a cikin dukkan ƙwayoyin cuta na RNA, maye gurbi a cikin mura yana faruwa akai-akai saboda RNA polymerase na ƙwayar cuta ba shi da hanyar gyarawa, wanda ke haifar da ƙimar kuskure tsakanin maye gurbin 1 da 8 a kowace wuri a kowace shekara yayin kwafi na kwayar cutar. [1] Sauye-sauye a cikin sunadaran saman suna ba da damar ƙwayar cuta ta guje wa wasu garkuwar jiki, kuma lambobi da wuraren waɗannan maye gurbi waɗanda ke ba da mafi girman adadin kubuta daga garkuwar jiki ya kasance muhimmin batu na nazari tsawon sama da shekaru goma. [2] [3] [4]
Duba kuma
[gyara sashe | gyara masomin]- Canjin hana ƙwayoyin cuta (antigenic reflux)
- Asalin zunubin antigenic
Manazarta
[gyara sashe | gyara masomin]- 1 2 Oransky, Ivan (2005-05-14). "Maurice R Hilleman". The Lancet (in Turanci). 365 (9472): 1682. doi:10.1016/S0140-6736(05)66536-1. ISSN 0140-6736. PMID 15912596. S2CID 46630955.
- 1 2 Kurth, Reinhard (April 2005). "Maurice R. Hilleman (1919–2005)". Nature (in Turanci). 434 (7037): 1083. doi:10.1038/4341083a. ISSN 1476-4687. PMID 15858560.
- ↑ D. J. D. Earn; J. Dushoff; S. A. Levin (2002). "Ecology and Evolution of the Flu". Trends in Ecology and Evolution. 17 (7): 334–340. doi:10.1016/S0169-5347(02)02502-8.
- ↑ Boni, T; S. Cobey; P. Beerli; M. Pascual (2006). "Epidemic dynamics and antigenic evolution in a single season of influenza A". Proceedings of the Royal Society B. 273 (1592): 1307–1316. doi:10.1098/rspb.2006.3466. PMC 1560306. PMID 16777717.
- ↑ Bouvier NM, Palese P (Sep 2008). "The biology of influenza viruses". Vaccine. 26 (Suppl 4): D49–53. doi:10.1016/j.vaccine.2008.07.039. PMC 3074182. PMID 19230160.
- ↑ Nelson, M. I.; Holmes, E. C. (March 2007). "The evolution of pandemic influenza". Nature Reviews Genetics. 8 (3): 196–205. doi:10.1038/nrg2053. PMID 17262054. S2CID 221107.
- 1 2 Hensley, S. E.; Das, S. R.; Bailey, A. L.; Schmidt, L. M.; Hickman, H. D.; Jayaraman, A.; Viswanathan, K.; Raman, R.; Sasisekharan, R.; Bennink, J. R.; Yewdell, J. W. (30 October 2009). "Hemagglutinin receptor binding avidity drives influenza A virus antigenic drift". Science. 326 (5953): 734–736. Bibcode:2009Sci...326..734H. doi:10.1126/science.1178258. PMC 2784927. PMID 19900932. Cite error: Invalid
<ref>tag; name "Hensley 2009 734–736" defined multiple times with different content. - ↑ Taubenberger, Jeffery K.; Kash, John C. (17 June 2010). "Influenza virus evolution, host adaptation and pandemic formation". Cell Host & Microbe. 7 (6): 440–451. doi:10.1016/j.chom.2010.05.009. PMC 2892379. PMID 20542248.
- ↑ Bush, R. M.; K. Subbarao; N. J. Cox; W. M. Fitch (3 December 1999). "Predicting the evolution of human influenza A". Science. 286 (5446): 1921–1925. doi:10.1126/science.286.5446.1921. PMID 10583948. S2CID 2836600.
- ↑ Carrat F, Flahault A (September 2007). "Influenza vaccine: the challenge of antigenic drift". Vaccine. 25 (39–40): 6852–62. doi:10.1016/j.vaccine.2007.07.027. PMID 17719149.