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  DERMATOPHYTE  Infection caused by fungi is known as mycosis  Types: Superficial Subcutaneous Systemic SUPERFICIAL : Affect surface  Types : Superficial infection  Example -Tinea nigra,Piedra Cutaneous :Dermatophyte  DERMATOPHYTE : Superficial mycoses that affect only superficial keratinised tissue (hair,skin,nail) Break down and utilise keratin Infection caused it DERMATOPHYTOSES,tinea or ringworm GENUS ORDER  TRICHOPHYTON-Hair,skin,nail MICROSPORUM-hair,skin EPIDERMOPHYTON-skin,nail CLINICAL TYPES: Named based on site of involvement  Scalp-tinea capitis Groin-tinea cruris No hair involvement -tinea corporis Foot-tinea pedis or athlete's foot Beard -tinea barbae or barber's itch Chronic type with hair involvement is called FAVUS  FAVUS is followed by alopecia and scaring Its of two types ectothrix,endothrix Atherospore sheath over the hair shaft-ectothrix Atherospore within hair shaft -endothrix LAB DIAGNOSIS : SPECIMEN : Hair scraping,skin scraping ,nail DIRECT MICROSCOPY  1

  HUMAN IMMUNODEFICIENCY VIRUS  HUMAN -It can live only in human IMMUNODEFICIENCY -Damages the immune system of people it infects  VIRUS -Retrovirus (RNA) MORPHOLOGY: Spherical enveloped virus diameter :90-120 nm composed of 2 copies of positive single stranded RNA enclosed by conical capsid composed of viral protein p24 RNA genome consist of 9 gene  3 genes :gag,pol,env contain information needed to make the structural protein for new virus particle CAPSID : There are 3 enzyme required for HIV replication  REVERSE TRANSCRIPTASE INTEGRASE PROTEASE MATRIX: Composed of viral protein p17 surrounds the capsid  ensuring integrity of virion particle surrounded by phospholipid spikes 2 units -gp41 and gp120  PATHOGENESIS: 1)HIV attachment to host CD4 cell 2)Reverse transcriptase makes DNA from the virus RNA 3)Integration into host cells nucleus 4)Reproduction of viral components 5)Assembly of new HIV viruses 6)Virus release by budding (enzyme -protease) 7)Viral replication ,fusion,integrase 8

  ELISA  Its simple ,nearly as sensitive as radioimmunoassay It has wide range of application Used for detection of specific antigen/antibody PRINCIPLE: Enzyme is used to detect antigen antibody reaction  Colour change is the indication for detection Its carried in polyvinyl plates ,polystyrene plate. TYPES 1) SANDWICH ELISA: In a microtitre plate ,wells are coated with specific antibody eg- e.coli -antigen test,specific antibody is placed. Specimen to be tested is added If the specimen contains suspected antigen (antigen-antibody reaction) to detect this reaction ,anti-serum conjugated with an enzyme is added it binds to antigen that's already attached to antibody Positive results : Enzyme+antiserum  act on substrate produce colour that's read by elisa reader. 2) INDIRECT ELISA: Microtitre plate wall coated with specific antigen that help in detection of antibody If positive antigen -antibody reaction occur  Substrate: antibody to antigen conjugated , enzyme is added Substrat

  IMMUNOLOGY -PART 1  DEFINITION OF IMMUNITY Resistance exhibited by the host against any foreign antigen including microorganism TYPES OF IMMUNITY: A) INNATE IMMUNITY B) COMBINED C) MISCELLANEOUS A) INNATE IMMUNITY It is the resistance possessed by birth,by virtue of genetic and constitutional make up . It does not depend on prior contact with foreign antigen. TYPES: SPECIES IMMUNITY Resistance to a pathogen Shown by all members of particular species Eg- Bacillus Anthracis infect human,chicken does not get affected. RACIAL IMMUNITY Within 1 species,different resistance to infection INDIVIDUAL IMMUNITY In same race and species there will definitely be difference in resistance to infection For example: imagine  you and our friend of same age group ,the resistance to infection might be at least slightly higher or even lower than your friend it depends on the individual . FACTORS INFLUENCING INNATE IMMUNITY; AGE: Foetus and old person they both high susceptibility to various infection as

  CULTURE MEDIUM AND CULTURE MEDIA  CULTURE MEDIUM: DEFINITION: A chemically prepared solid /liquid substance used to support the growth of microorganism Uses :  To provide nutrition To provide space To provide growth To increase population To handle stress To differentiate species  COMPONENTS: 1) NITROGEN SOURCE- Amino,protein extract,peptone 2) Growth factor- Blood serum,meat,yeast extract 3)Energy- Sugar,alcohol,carbohydrate 4)Buffer - Maintain ph ,phosphate,acetate  5) Salt- Enhance growth,phosphate ,sulfate,magnesium SELECTIVE AGENTS: CHEMICAL ANTIBIOTICS INDICATOR DYE GELLING AGENT :  Act as solidifying agent  agar ,gelatin- agents CULTURE MEDIA  Culture media is required to grow organism from infected material to identify the causative agent It contains: water,vitamin,mineral,growth factor,blood,serum,agar,peptone   TYPES : SIMPLE COMPLEX SPECIAL: ENRICHED,ENRICHMENT,SELECTIVE,DIFFERENTIAL,INDICATOR,TRANSPORT,SUGAR  SYNTHETIC ANAEROBIC : DEHYDRATE  SIMPLE: Nutrient broth - pepto

  STAPHYLOCOCCUS 🦠 Staphylococci are gram positive cocci arranged in grape like cluster The pathogenic medically important species: 1)Staphylococcus aureus  2) Staphylococcus epidermidis 3) Staphylococcus saprophyticans Morphology : Non motile Non sporing 1 micro meter in diameter Culture :  They grow on ordinary culture media at 37 degree Celsius temperature They are aerobe and facultative anaerobe 1) Nutrient agar :  After 24 hours incubation,colonies : circular,smooth,convex 2) Blood agar: Colonies similar to nutrient agar 3)Macconkey agar: Colonies : small and pink 4)MANNITOL SALT AGAR:  This is both selective and an indicator medium  Colonies : yellow colored  Toxin 1) Staphylococci produce 4 antigenically distinct type of exotoxin Alpha lysin: Lytic to rabbit erythrocyte ,less active against sheep or human red cell It is cytotoxic ,leucocidal and dermonecrotic Beta lysin: Lytic to sheep cell but not to human or rabbit erythrocyte Hot -cold phenomenon : lysis is initiated at 37 d

  CULTIVATION OF VIRUS  Virus are smallest obligate intracellular infective agent containing only one gene type of nuclei acid ( DNA/RNA) as their genome. Virus multiply only in living cells They cannot be grown on inanimate culture medium. METHOD OF VIRUS CULTIVATION : 1)Animal inoculation 2) Embryonated egg inoculation 3) Tissue culture  1) ANIMAL INOCULATION: Three main reason why animal inoculation is used for  Primary isolation of certain viruses  To study pathogenesis of viral diseases  To study viral oncogenesis Isolation of arbovirus,coxsackie virus is done on INFANT MICE. Route of inoculation :intracerebral,subcutaneous,intranasal. After inoculation: animals are observed for sign of disease or death. Later on they are sacrificed and tissues are tested for the presence of virus. Other animal such as guinea pig,rabbit and ferrets are also used in some situation. 2 EMBRYONATED EGG INOCULATION  Inoculation of embryonated hens egg ( 7-12 days old) are inoculated by one of the sever

                          HYPERSENSITIVITY   hello, doctor vanakam, I hope you all are doing good, as intimated through the last post on anaerobic culture method  https://www.stencildent.com/2020/08/anaerobic-culture-methods-microbiology.html  if u haven't checked it out do read using this link without any further ado lets get started. CONTENTS: 1)Definition 2)Classification 3)type 1 hypersensitivity reaction a)1st exposure b)2nd exposure c)mediators of reaction d)late-phase reaction 4)type 4 hypersensitivity 5)treatment  1)DEFINITION: It refers to a condition in which immune response results in excessive reaction leading to tissue damage, disease, or even death in a sensitised host. 2) CLASSIFICATION: Coomb and gel classification in 1963 into type 1 to 4  Type 1,    type 2, type 3       : They depend on the interaction of antigen with humoral antibodies They are the immediate-type reaction  type 4 : They are mediated by t lymphocyte Delayed-type of hypersensitive reaction 3)TYPE 1

          ANAEROBIC CULTURE METHOD  Hello, doctor vanakam,  The topic of discussion for today is anaerobic culture methods as informed in the previous post on the healing of tissues  https://www.stencildent.com/2020/07/healing-of-tissue-repairprocess.html  if you haven't checked the previous post do check it out using this link without any further ado lets get started.  CONTENT :  1) INTRODUCTION  2)CLASSIFICATION OF ANAEROBE  3)METHODS TO ACHIEVE ANAEROBIOSIS 1) INTRODUCTION : Anaerobic bacteria have grown only in the absence of oxygen These conditions are called as anaerobiosis Anaerobic media are used for cultivation of anaerobic bacteria Types of anaerobes: Obligate, eg: Clostridium tetani, Aero-tolerant, eg: clostridium histolyticum Facultative  2) CLASSIFICATION OF ANEROBE:                                                             ANAEROBIC BACTERIA  BACILLI                                                                                                  COCCI GRAM POSITI