12. Hyalinosis: definition, classification, causes, mechanisms of development. Macro- and microscopic changes in the connective tissue. Disease examples.

Hyalinosis is the formation of homogeneous translucent dense masses in connective tissue, resembling hyaline cartilage - hyaline. Hyaline consists of 1. fibrin and other plasma proteins 2. lipids 3. immunoglobulins. Sharply CHIC-positive, yellow-red when stained with picrofuxin. Mechanism of development: destruction of fibrous structures, increase in tissue-vascular permeability  precipitation of plasma proteins on altered fibrous structures  formation of hyaline.

Classification:

1. Vascular hyalinosis a. systemic b. local

2. hyalinosis of the connective tissue proper

1. system

2. local.

Pathological processes, the outcome of which develops hyalinosis:

a) vessels: 1. Hypertension, atherosclerosis (simple hyaline) 2. diabetic microangiopathy (diabetic arteriologialinosis - lipogyalin) 3. rheumatic diseases (complex hyaline) 4. local physiological phenomenon in the spleen of adults and the elderly ("glazed spleen").

b) connective tissue proper: 1. rheumatic diseases 2. locally in the bottom of a chronic ulcer, appendix 3. in scars, fibrous adhesions of cavities, vascular wall in atherosclerosis.

The pathomorphology of vascular hyalinosis (mainly small arteries and arterioles are affected, is systemic in nature, but is most characteristic of the vessels of the kidneys, pancreas, brain, retina):

• Micro: hyaline in the subendothelial space; thinned media.

• Macro-: vitreous vessels in the form of dense tubes with a sharply narrowed lumen; atrophy, deformation, wrinkling of organs (for example, arteriosclerotic nephrocyrrhosis).

Pathomorphology of hyalinosis of the connective tissue proper:

• Micro-: swelling of connective tissue bundles; loss of fibrillarity, fusion into a homogeneous dense cartilaginous mass; cellular elements are compressed, undergo atrophy.

• Macro-: the tissue is dense, whitish, translucent (for example, hyalinosis of the heart valves in rheumatism).

Hyalinosis outcomes (more often unfavorable): 1. resorption (in keloids, in mammary glands under the condition of hyperfunction) 2. obliteration 3. rupture of hyalinized vessels with increased blood pressure, hemorrhages

Functional significance: widespread hyalinosis of arterioles  functional organ failure (CRF in arteriosclerotic nephrocyrrhosis); local hyalinosis of the heart valves  heart defect.

13. Amyloidosis: definition, classification, mechanisms of development, structure of amyloid. Methods for detecting amyloid in tissues.

1. Amyloidosis (amyloid dystrophy) is a stromal vascular dysproteinosis accompanied by a profound violation of protein metabolism, the appearance of abnormal fibrillar protein and the formation of a complex substance in the interstitial tissue and vascular walls - amyloid.

2. Theories of the pathogenesis of amyloidosis:

a) immunological (amyloid as a result of the interaction of AH and AT)

b) the theory of local cellular synthesis (amyloid is produced by cells of mesenchymal origin)

c) mutation theory (amyloid is produced by mutant cells)