HIV SeropositivityHIV SeroprevalenceHIV InfectionsSubstance Abuse, IntravenousSexual BehaviorRisk FactorsS PhaseDisease ProgressionSeroepidemiologic StudiesG1 PhaseCell CycleCell Cycle ProteinsCyclin-Dependent Kinase 4Cyclin-Dependent KinasesCyclin D1Cyclin ECyclin DAntibodies, ViralCyclin-Dependent Kinase 2Cyclin-Dependent Kinase Inhibitor p27Retinoblastoma ProteinDNA ReplicationCyclinsAntibodies, BacterialChlamydophila pneumoniaeProtein-Serine-Threonine KinasesImmunoglobulin GG0 PhaseChlamydophila InfectionsCyclin AEnzyme-Linked Immunosorbent AssayG2 PhaseSerologic TestsCDC2-CDC28 KinasesHIV SeronegativityTime FactorsPrevalenceCell DivisionHydroxyureaBromodeoxyuridineMitosisE2F1 Transcription FactorCell Line, TumorHelicobacter pyloriHelicobacter InfectionsCell ProliferationPhosphorylationE2F Transcription FactorsCell LineSignal TransductionAcquired Immunodeficiency SyndromeToxocariasisNuclear ProteinsDNA-Binding ProteinsHIV-1Antibodies, ProtozoanRNA, Small InterferingDNA DamageCytomegalovirus InfectionsHeLa CellsBlotting, WesternTranscription FactorsProto-Oncogene ProteinsTumor Suppressor ProteinsChromatinMutationCross-Sectional StudiesCells, CulturedCase-Control StudiesToxoplasmosisFlow CytometryHepatitis CHerpesvirus 2, HumanToxocaraRNA, MessengerAIDS SerodiagnosisMolecular Sequence DataBlood DonorsCohort StudiesProtein BindingPapillomavirus InfectionsApoptosisProspective StudiesNeosporaCD4 Lymphocyte CountAge FactorsTumor Cells, CulturedCyclin-Dependent Kinase Inhibitor p21DNACytomegalovirusRural PopulationProtein KinasesHerpes GenitalisSyphilisImmunoglobulin AHuman papillomavirus 16BrazilToxoplasmaTransfectionHomosexuality