پاورپوینت ایدز و لنتی ویروس ها ( به زبان انگلیسی )

Introduction
Human immunodeficiency virus (HIV)    derived from primate lentiviruses etiologic agents of AIDS
The illness was first described in 1981 and was isolated by the end of 1983
once infected, individuals remain infected for life
Within a decade, if left untreated, the vast majority of HIV-infected individuals develop fatal opportunistic infections as a result of HIV-induced deficiencies in the immune system.
AIDS    the most important public health problems worldwide at the start of the 21st century.
Virion: Spherical & cylindric core 
Genome: Single-stranded RNA, linear, positive-sense, diploid 
Proteins: Envelope glycoprotein undergoes antigenic variation; reverse transcriptase enzyme contained inside virions; protease required for production of infectious virus 
Envelope: Particles bud from plasma membrane 
Replication: Reverse transcriptase makes DNA copy from genomic RNA; provirus DNA is template for viral RNA. Genetic variability is common. 
Outstanding characteristics:   
nononcogenic
may be cytocidal
Infect cells of the immune system  
Cause slowly progressive, chronic diseases
4 genes required for a replicating retrovirus     gag, pro, pol, and env
Up to 6 additional genes regulate viral expression and are important in disease pathogenesis in vivo.