General pathology
Download
1 / 26

General Pathology - PowerPoint PPT Presentation


  • 189 Views
  • Uploaded on

General Pathology. Basic Principles of Cellular and Organ Pathology Autogenous Pigments. Jaroslava Dušková Inst. Pathol. ,1st Med. Faculty, Charles Univ. Prague. Pigments. Definition: colored substances in the organism or environment. Pigments. Classification: endogenous

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about ' General Pathology' - dimaia


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
General pathology
General Pathology

Basic Principles of Cellular and Organ Pathology

Autogenous Pigments

Jaroslava Dušková

Inst. Pathol. ,1st Med. Faculty, Charles Univ. Prague


Pigments
Pigments

Definition:

colored substances

in the organism

or environment


Pigments1
Pigments

Classification:

  • endogenous

    • autogenous

    • hemoproteins derived

  • exogenous


  • Autogenous pigments
    Autogenous Pigments

    -color substances formed in the organism as metabolism products

    • melanin

    • ceroid

    • lipofuscin


    Melanin
    Melanin

    • oculocutaneous

      (origin from tyrosine in melanocytes)

    • neuromelanin - subst. nigra

      (origin from dopamin)


    Melanin types
    Melanin - types

    • eumelanin – insoluble , brown-black

    • phaeomelanin – soluble, yellow-red (high sulphur content)


    Melanin production
    Melanin - production

    Melanocytes

    • derived from the neural crest

    • present in the basal layer of epidermis, dermis, hair folicles, mucose membranes, uveal tract of the eye, meninges, inner ear

    • secretory in the contact with the epithelial cells - cytocrinia


    Melanin functions 1
    Melanin Functions – 1.

    • cytoprotective

      • light absorption & conversion of the photon energy into heat

      • uvea – absorption of the light retina protection of light overexposure

      • retina - visual acuity preventing light reflexion from the fundus


    Melanin functions 2
    Melanin Functions -2.

    • Ion exchanging capacity

      Melanosomes can also act as detoxyfiing and excretory components accumulating great number of drugs and toxic component e.g. heavy metals.

      Scavengers of the free radicals.

      Rarely cytotoxic – photosensibilisation


    Melanin features
    Melanin - Features

    • brown

    • destained with H2O2

    • reducing AgNO3


    Disorders of melanin pigmentation

    Lack

    generalized

    total albinism

    parcial albinism

    local

    vitiligo

    leucoderma

    Disorders of Melanin Pigmentation


    Albinism
    Albinism

    • autosomal recessive heredity

      • tyrosinase deficiency

      • tyrosinase positive – melanosomes defect

    • oculo-cutaneous albinoidism – dominant inheritance


    Disorders of melanin pigmentation1

    Lack

    generalized

    total albinism

    parcial albinism

    local

    vitiligo

    leucoderma

    Disorders of Melanin Pigmentation


    Vitiligo
    Vitiligo

    • familial aggregation

    • polygenic nature

    • association with other autoimmune diseases (DM, thyroiditis, gastritis)

    • ab against tyrosinase in the serum

    • autoreact . T- cellular cytotoxicity


    Disorders of melanin pigmentation2

    Lack

    generalized

    total albinism

    parcial albinism

    local

    vitiligo

    leucoderma

    Disorders of Melanin Pigmentation


    Leucoderma
    Leucoderma

    • postinflammatory circumscribed depigmentation e.g.

      • leucoderma syphyliticum

      • leucoderma psoriaticum


    Disorders of melanin pigmentation3

    Increase

    generalized

    Adison disease

    local

    freckles, nevi

    chloasma /melasma

    melanodermia

    melanoma

    Disorders of Melanin Pigmentation


    Disorders of melanin pigmentation4

    Increase

    generalized

    Adison disease

    local

    freckles, nevi

    chloasma

    melanodermia

    melanoma

    Disorders of Melanin Pigmentation


    Disorders of phenylalanine and tyrosine metabolism
    Disorders of Phenylalanine and Tyrosine Metabolism

    1. Phenylalanine hydroxylase PHENYLKETONURIA

    2. Homogentisic acid oxydase

    ALKAPTONURIA

    3. Tyrosinase ALBINISM


    Disorders of phenylalanine and tyrosine metabolism1
    Disorders of Phenylalanine and Tyrosine Metabolism

    Phenylalanine

    Tyrosine

    1

    3

    Homogentisic

    acid

    DOPA

    2

    cc

    methyl–

    acetoacetic

    acid

    Norepinephrine

    Epinephrine

    MELANIN


    Ceroid
    Ceroid

    • features

      • light brown

      • PAS +

      • acidoresistent

      • Sudan +-

    • origin

      • fagocytosis od lipid substances by macrophages

      • oxidation of non–saturated lipid acids


    Ceroid1
    Ceroid

    • localisation

      • places of erythrocytes destruction

      • necroses of adipous tissue

      • avitamonosis E

      • melanosis coli

      • Dubin - Johnson syndrome


    Lipochrom
    Lipochrom

    • ubiquitous pigment

    • exogenous origin

    • lipid solvent

    • histologically unprovable


    Lipofuscin
    Lipofuscin

    • features

      • dark brown

      • Sudan +-

      • autofluorescence


    Lipofuscin1
    Lipofuscin

    • origin

      • autophagocytosis

        "wear and tear" pigment

        from the accumulation

        of autophagolysosomes over time.


    Lipofuscin2
    Lipofuscin

    • localisation

      • CNS, epithels, muscles, liver

        ATROPHIA FUSCA


    ad