Micro E2 Notes - How we obtain a virus: 1  ­Cell...

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Unformatted text preview: How we obtain a virus: 1  ­Cell must have receptor for virus nd 2  ­Once in cell virus must be uncoated rd 3  ­Viral DNA enters nucleus th 4  ­Golgi makes new protein coat ­Capsid (Nucleic Acid genome lodges for protection) th 5  ­Pick up envelop from host cell membrane (Nuclear membrane) th 6  ­Virus can burst (Lyse) out of the cell or leave without any issue Interferon=blocks viral protein synthesis MHC ­1=Endogenous, displays proteins to T cells so that T cells will kill the infected cell MHC ­2=Exogenous, found on antigen presenting cells (macrophages, dendrite cells and B cells) End result to a viral infected cell=destroyed by T cytotoxic cell (known as cell mediated immunity) st Virus Info: Viruses are either DNA or RNA (NOT both) Protein building blocks form tight shell known as a capsid DNA viruses ­messenger RNA codes for viral proteins RNA viruses ­carry RNA polymerase, which directs transcription and replication (Replicates RNA in the cytoplasm) Viruses need live cells to grow NBQ ­Aids attacks MHC ­II PFU ­Plaque forming unit FFU ­Focus forming unit Side Note: Epidemic ­Occurrence of cases of illness in a community or region which is in excess of the number of cases normally expected for that disease in that area at that time. Retrovirus: Reverse Transcriptase ­RNA dependent DNA polymerase Provirus ­When DNA is inserted into the cells Influenza virus: 3 types ­A, B and C A and B cause epidemic issues Complications of Influenza ­Guillain Barre’ Syndrome & Reye’s Syndrome (Autoimmune reaction) Vaccine contains dead strands of A and B (elicits immune response ­Antibody production) Flu Mist ­Attenuated virus (live) elicits both cellular and humoral immunity Rhinovirus: RNA virus AKA ­Common head cold 110 serotypes (different forms) ­many different forms prevents us from building up immunity to all Grows best at 33°C (91.4°F) Person to person transmission (Inhalation) Link between Rhinovirus and hospitalization when children have wheezing or asthma Symptoms: Sore throat and mucopurulent nasal discharge (runny mucous) Mucopurulent ­Can cause other bacteria to get into sinuses, predisposing you to secondary bacterial infections Coronavirus: RNA virus Causes 1/3 of all colds, also cause lower respiratory tract infections Severe Acute Respiratory Syndrome (SARS) caused by Coronavirus Adenovirus: DNA virus 42 known human serotypes (which cause many different issues) Could possibly be linked to obesity (especially in animals) Flu like symptoms but not the flu, usually indicates Adenovirus Types of infection ­Lytic and Oncogenic Associated with Pertusis in kids, musculoskeletal disorders, Gastroenteritis, Hepatic disorders Respiratory Syncytial Virus (RSV): RNA virus Causes primary pneumonia among infants (.5% ­2% require hospitalization) (can lead to death, 1% mortality) Vaccine ­Gamma globulin is available (pool of antibodies), prophylactic treatment with antibodies from adult Fifth Disease/Erythema Infectiosum: Causes rash in children, also can cause Aplastic anemia in children that have blood disease (chronic anemia) Grows in stem cells Rash ­“slapped ­cheek” or “lacy” rash Human parvovirus B19 causes fifth disease Varicella (chickenpox)/VZV (Varicella Zoster Virus): Member of the Herpesviridae family Varicella virus ­double stranded DNA virus Transmitted by respiratory droplets and skin contact Can get into lungs Vaccine is live (attenuated) vaccine Herpes Zoster is the recurrent infection (AKA shingles) Herpes Zoster/Shingles: Recurrent infection of Varicella (chickenpox) Complications ­Postherpatic Neuralgia (PHN), Opthalmic Zoster, Skin eruptions and CNS involvement Virus hides out in the Dorsal Root Ganglion Polio/Poliomyelitis: Smallest of the RNA viruses Primarily a G.I. tract infection Paralysis is a rare outcome and associated with Bulbar polio (effects medulla) Type I ­Brunhilde Strain Type II ­Lansing Type III ­Leon Strain Polio vaccine is Trivalent ­contains all three strands Most polio virus infections are asymptomatic Salk ­came out with injectible vaccine (inactivated form) (it is the vaccine that is used today) Sabin ­came out with attenuated virus Hepatitis A: Infectious Hepatitis Occurs through ingestion of fecal matter (fecal ­oral) Occurred at a local McDonald’s recently Men having sex with men (MSM) Also get through shellfish People get post exposure profilactus vaccine Resolves with time Can cause liver damage ­(would have to eat baby food for 6 months, no alcohol for 1 year) Hepatitis B: DNA virus ­could cause cancer Serum hepatitis Contact with infectious blood, semen and other bodily fluids Sharing of needles (needle sticks) Among unimmunized persons, occurs in more than 90% of infants ­those infants will become chronic carriers Hepatitis C: Get through contact with blood of an infected person Causes liver damage 70% of chronically infected persons develop chronic liver disease Hepatitis D: Relies on HBV to replicate (“piggy backs” on HBV) Viral Gastroenteritis: Virus in G.I. tract Explosive onset with varying combination of diarrhea, nausea, vomiting, low grade fever, cramps, headache Caused by Reoviridae Reoviruses ­enter oropharynx, we can pass when it is in the upper respiratory system REO ­Respiratory Enteric Orphan (orphan means that it doesn’t cause any famous disease) Rotavirus: Lyses mucosal linings ­makes absorbing water difficult ­leading to diarrhea Most common cause of severe diarrhea among children, resulting in hospitalization Enteroviruses: Noroviruses named after original strain Norwalk virus Extremely infectious, dehydration is the most common complication Environmental and fomite contamination may act as a source of infection Recently the virus shut down cruise ships Coxsackie virus: Symptoms can be similar to strep Many conditions could possibly occur Pleurodynia (lungs), meningitis, myocardiopathy (heart) Diabetes Mellitus can occur ­virus gets into pancreas→ destroys it and causes Type 1 diabetes Hand, Foot and Mouth Disease ­rash on feet, hand, and in pharynx Echovirus: ECHO ­Enteric (Intestinal), Cytopathogenic (Pathogenic), Human (Human location), Orphan (produces no famous disease) Survives in water and sewage Arboviruses: Mosquito born viruses ­includes West Nile virus, Dengue virus and Yellow Fever West Nile virus: Symptoms are asymptomatic Need to protect older adults Many mosquito strains can transmit virus Dengue Fever: Caused by Aedes mosquito (Egyptus mosquito) 4 Types: DEN ­1, DEN ­2, DEN ­3, DEN ­4 May have high fever ­ 105° Yellow Fever: Belongs to the Flavivirus group Also caused by Aedes mosquito Characterized by fever, muscle pain (prominent backache), headache, shivers 15% of individuals enter a toxic phase within 24 hours and die Epstein ­Barr virus (E.B.V) Member of Herpesviridae family Implicated in African ­Burkitts’ lymphoma, anaplastic nasopharyngeal carcinoma, B ­cell lymphomes (in Aids and immunosuppressed) Infects B ­cells, transforms them into immortal, continuously dividing cells Will have raised lymphocyte and monocyte count Atypical lymphocytes=Downey cells Infectious mononucleosis ­“kissing dsease”, contracted via mouth to mouth Symptoms ­sore throat, swollen lymph glands, swollen spleen or liver (similar to Aids symptoms) Burkitts lymphoma ­Associated with Epstein Barr Virus, occurs endemically in African and New Guinea(in children) May follow infection with malaria Nasopharyngeal Carcinoma ­cancer associated with E.B.V, effects epithelium of the nasopharynx Cytomegalovirus: Member of the Herpesviridae family Transmitted to child in womb (crosses placenta): (may require IgG’s ­they cross placenta) Can be in saliva, blood, breast milk Children who are infected ­80 ­90% will have complications such as hearing loss, vision impairment and mental retardation Can cause retinitis in Aids patients Effects leukocytes in immunosuppressed individuals Rabies: Rhabdoviridae family Negri bodies ­characteristic cytoplasmic inclusion bodies Vectors ­skunks, raccoons, bats Disease takes time to replicate Shots include HDCV and HRIG (IgG antibody) Herpes Simplex: DNA virus Lipchutz bodies ­indicate you are infected (HSVI or HSVII) Neonatal herpes ­life threatening disease, 3 forms: cutaneous lesims, generalized infection, encephalitis Virus hides out in C.N.V Trigeminal HSV I ­oral, cold sores (cold sores are indicators of the second emergence of the virus) HSV II ­genital (often emotional issues accommodate) HSVI/HSVII ­one can become the other Episomal form ­latent stage of the disease Warts: Papillomavirus, DNA virus HPV or Cervical cancer is considered to be an STD HPV will cause mild pap test abnormalities 1/3 of the different types lead to the development of cervical cancer Guardisil is the vaccine given to help prevent HPV MMR ­ Measle Mumps and Rubella: Vaccine is attenuated Measles: Spreads through the air by breathing, coughing or sneezing Koplik’s spots ­white spots inside mouth (rash on mucous membrane) 1 ­2/1000 children die of measles Young and old can get hospitalized Mumps: Spread by droplets of saliva or mucous Effects Parotid gland Causes Orchitis ­ inflammation of testis (leads to fertility problems) Prior to vaccine era deafness was a major complication of mumps Rubella ­German Measles (Three day Measles) Spread by respiratory droplets May cause fetal death, spontaneous abortion, or premature delivery Deafness, Eye defects (cataracts, glaucoma, retinopathy), cardiac defects and neurologic abnormalities Complications may be delayed for a couple of years Fungus Here is what I got for the fungus information, it was hard to follow her cause she went through it fast. Overview Fungus starts out as a spore then grows to mold then onto mold Fungus is a eukaryotic cell type with a distinct nucleus, its heterotropic, principally saprophytic Cell wall is made of cellulose and chitin Cell membranes contain ergosterol, which is the target for some antifungal drugs Mycelium (book def.) ­mass of filamentous cells of a fungus Hypha ­ individual filament of fungal cells, can be septate or non ­septate (aseptate), produce spores Septate ­ walls with a nucleus in it Non ­septate (Aseptate) ­ nucleus and no wall Unicellar fungi are reffered to as yeasts Pathogenesis of fungi Aspergillus spp. ­ produces aflatoxin (carcinogen) when it grows on some foods Claviceps purpurea grows on grains (e.g. rye), may result in necrosis and gangrene as a result of ergot alkaloids Sabouraud’s dextrose agar ­ used to grow fungi Saccharomyces (3 different types) ­ good yeast, source of B vitamins Candida albicans ­produce pseudohyphae which are believed to invade mucous membranes Cryptococcus neoformans ­produce large mucopolycaccharide capsule that protects it from phagocytosis Clinical condition: Systemic mycoses ­ it will kill you Diagnosis KOH Prep: Specimens are obtained by skin scraping Wood’s Lamp: Uses a UV light to look for fungal skin infections Superficial Mycoses Effect outermost layer of the skin or hair Pityrosporum orbiculare (Malassezia furfur) Lipophilic yeast Causes pityriases versicolor or tinea versicolor which causes hypopigmentation Lesions do not tan (white spots) Piedraia hortae may appear as white or black growths on the hair Cutaneous Mycoses (Dermatomycoses) Effect deeper layers of the epidermis Three genera of dermatophytes: Epidermophyton, Trichophyton, Microsporium Causes ringworm or tinea (no actual worm) Many different types of tinea Systemic Mycoses 5 genera to know: Histoplasma, Blastomyces, Coccidiodes, Paracoccidioides, Cryptococcus Histoplasma capsulatum Mississippi Valley Fever Histoplasmosis, also known as Darling’s disease Grows in bat and bird droppings Found in and near the Ohio River and Mississippi river Blastomyces dermatitidis Blastomycosis, aka Chicago Disease Found overlapping endemic areas of Histoplasma Coccidioides immitis Coccidioidomycosis, aka San Joaquin Valley Fever Found in rodent droppings Cryptococcus neoformans European blastomycosis Found in Pigeon droppings Grows best at 25°C and 37°C as a yeast Has mucopolysaccharide capsule, which makes it hard for us to make a response to Goes from lungs to brain, may be mistaken for lung cancer Opportunistic Mycoses Candida albicans Results in candidiasis, yeast infections, thrush Aspergillus species (flavus & fumigates) Causes Apergillosis Pneumocystis carinii (jiroveci) severe issue for immunosuppressed individuals common cause of death for AIDS patients ...
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This note was uploaded on 05/03/2011 for the course BIO 1 taught by Professor Paul during the Spring '11 term at Palmer Chiropractic.

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