Brunner's gland hamartoma and hyperplasia

Hyperplasia is an increase in the number of cells in a tissue or organ due to enhanced cell division. It is an adaptive, controlled response to stimuli such as injury, hormones, or stress, involving mitosis to produce genetically identical cells and support tissue repair and regeneration.Tissue CapacityCertain tissues, including the epidermis, intestinal epithelium, bone marrow, and fibroblasts, have a high potential for hyperplasia. Others, such as bone, cartilage, and smooth muscle, show...

Goiter refers to an abnormal enlargement of the thyroid gland that may appear as a diffuse goiter (uniform enlargement) or nodular (single or multiple nodules). Functionally, it is classified as nontoxic (normal/low hormone levels) or toxic (excess hormone production).PathophysiologyDiffuse thyroid enlargement typically results from prolonged stimulation by thyroid-stimulating hormone (TSH) or TSH-like agents, commonly seen in hypothyroidism or iodine deficiency. In contrast, in hyperthyroid...

A hair follicle or HF is a small part of the skin that produces the hair shaft. Paul Gerson Unna was the first to observe a bulge in the human hair follicle's outer root sheath (ORS). The bulge is present between the sebaceous gland and the arrector pili muscle and is the niche for hair follicle stem cells (HFSCs). The bulge is also a niche for melanocyte stem cells, and their loss results in graying of hair. The HFSCs express Sox9 and Lhx2, which help them maintain stemness and prevent...

Hyperthyroidism is a hypermetabolic state caused by elevated levels of thyroid hormones, triiodothyronine (T3) and thyroxine (T4). It results from dysregulation at the thyroid, pituitary, or immune system level and affects multiple organ systems.PathophysiologyThe most common cause of hyperthyroidism is Graves’ disease, an autoimmune disorder in which antibodies, specifically thyroid-stimulating antibodies (TSAb), a subtype of TSH receptor antibodies (TRAb), bind to and activate TSH receptors...

Hyperthyroidism is a type of thyrotoxicosis characterized by the thyroid gland's overproduction of the thyroid hormones triiodothyronine (T3) and thyroxine (T4). This hormone excess increases the basal metabolic rate and enhances sensitivity to catecholamines.DiagnosisDiagnosis is based on clinical features and biochemical testing. It typically shows suppressed thyroid-stimulating hormone (TSH) levels below 0.4 mIU/L, with elevated free T3 and/or T4. Additional tests, including thyroid...

DysplasiaDysplasia refers to abnormal changes in the size, shape, and organization of mature cells, characterized by pleomorphism, nuclear abnormalities, and increased mitotic activity. It commonly affects epithelial tissues, including the cervix, gastrointestinal tract, respiratory mucosa, and endometrium. Although it may occur alongside hyperplasia, dysplasia is not a true adaptive response but a preneoplastic change with potential to progress to cancer.When confined above the basement...