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MORPHOLOGICAL REACTIONS TO ACUTE AND PERSISTENT STRESS HEALING REPAIR REGENERATION NEOPLASIA

MORPHOLOGICAL REACTIONS TO ACUTE AND PERSISTENT STRESS HEALING REPAIR REGENERATION NEOPLASIA. C ellular reaction var ies depending on the type duration and severity of injury. Adaptation a trophy h ypertrophy h yperplasia m etaplasia d ysplasia. HYPERTROPHY HYPERPLASIA.

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MORPHOLOGICAL REACTIONS TO ACUTE AND PERSISTENT STRESS HEALING REPAIR REGENERATION NEOPLASIA

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  1. MORPHOLOGICAL REACTIONS • TO • ACUTE AND PERSISTENT • STRESS • HEALING • REPAIRREGENERATION • NEOPLASIA

  2. Cellular reaction varies depending on the type duration and severity of injury

  3. Adaptation atrophy hypertrophy hyperplasia metaplasia dysplasia

  4. HYPERTROPHY HYPERPLASIA

  5. HYPERPLASIA and HYPERTROPHY are two distinct processes but frequently both occur together

  6. HYPERPLASIA takes place by contrast HYPERTROPHY involves _______________________________________

  7. HYPERTROPHY The increased size of the cells is due not to cellular swelling but to the synthesis of more structural components.

  8. HYPERTROPHY -physiologic -pathologic __________________________________ caused by increased functional demand or by specific hormonal stimulation

  9. - increased workload -hormonal stimulation

  10. HYPERPLASIA andHYPERTROPHY often occur concomitantly during the responses of tissues and organs to increased stress and cell loss even cardiac and skeletal muscles are capable of limited proliferation as well as repopulation from precursors

  11. MECHANISMS OF HYPERTROPHY • (cardiac muscle hypertrophy) • many signal transduction pathways • induction of a number of genes • stimulation of synthesis of cellular proteins

  12. GENES INDUCED DURING HYPERTROPHY

  13. - switch of contractile proteins from adult to fetal or neonatal forms - some genes that are expressed only during early development are re-expressed in hypertrophic cells

  14. TRIGGERS FOR HYPERTROPHY • IN THE HEART • -mechanical triggers • -trophic trigger

  15. HYPERTROPHY eventually reaches a limit

  16. The limiting factors for continued hypertrophy and the causes of the cardiac dysfunction are poorly understood

  17. HYPERPLASIA increase in the number of cells in an organ or tissue, usually resulting in increased volume of the organ or tissue

  18. PHYSIOLOGIC HYPERPLASIA hormonal hyperplasia compensatory hyperplasia wound healing s

  19. MECHANISMS OF HYPERPLASIA

  20. In hormonal hyperplasia, In compensatory hyperplasia

  21. PATHOLOGIC HYPERPLASIA

  22. Although these forms of hyperplasia are abnormal, the process remains controlled, because the hyperplasia regresses if the hormonal stimulation is eliminated That distinguishes benign pathologic hyperplasiasfrom cancer, in which the growth control mechanisms become defective.

  23. PATHOLOGIC HYPERPLASIA constitutes „a fertile soil in which cancerous proliferation may eventually arise.”

  24. METAPLASIA a reversible change in which one adult cell type (epithelial or mesenchymal) is replaced by another adult cell

  25. epithelial metaplasia columnar to squamous

  26. the influences that predispose to metaplasia if persistent, may induce malignant transformation ofmetaplasticepithelium

  27. epithelial metaplasia squamous to columnar type Barrett esophagus

  28. connective tissue metaplasia

  29. MECHANISMS OF METAPLASIA

  30. precursor cells differentiate along a new pathway

  31. Certain cytostatic drugs cause a disruption of DNA methylation patterns and can transform mesenchymal cells from one type to another

  32. NEOPLASIA

  33. what does it mean: • tumour • neoplasm • cancer • carcinoma

  34. TUMOR originally - swelling caused by inflammation tumor = neoplasm (leukemia is not a tumor )

  35. ONCOLOGY CANCER

  36. "A neoplasm • is an abnormal mass of tissue*, • the growth of which exceeds • and is uncoordinated • with that of the normal tissues • and • persists in the same excessive manner • after cessation of the stimuli • which evoked the change."

  37. All* neoplasms have two basic components: • (*almostall) • - proliferating neoplastic cells = parenchyma • - supportive stroma • made up of connective tissue • and blood vessels • neoplasms are critically dependent • on their stroma

  38. desmoplasia scirrhous

  39. NOMENCLATUREOF TUMORS is based on the parenchymal component _______________________________ tumors are designated by attaching the suffix -oma to the cell of origin

  40. Benign Malignant fibroma chondroma osteoma lipoma fibrosarcoma chondrosarcoma osteosarcoma liposarcoma Epithelial Non-epithelial adenocarcinoma squamous cells carcinoma adenoma papilloma

  41. BENIGN TUMORS e.g.

  42. MALIGNANT TUMORS sarcomas malignant tumors arising in mesenchymal tissue

  43. carcinomas malignantneoplasms of epithelial cell origin

  44. Not infrequently a neoplasm is composed of undifferentiated cells of unknown tissue origin and must be designated merely as „a poorly differentiated” or „undifferentiated malignant tumor”

  45. TERATOMAS

  46. polyp macroscopically visible projection above a mucosal surface

  47. look at the following slides, recognise the tissue of origin and name the neoplasms

  48. DIFFERENTIATION the extent to which neoplastic cells resemble comparable normal cells, both morphologically and functionally

  49. well-differentiated tumors poorly differentiated or undifferentiated tumors

  50. benign tumors are well differentiated

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