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Skeleton and Calcium Homeostasis01:21

Skeleton and Calcium Homeostasis

Calcium is not only the most abundant mineral in bone but also the most abundant mineral in the human body. Calcium ions are needed for bone mineralization, tooth health, heart rate regulation and strength of contraction, blood coagulation, the contraction of smooth and skeletal muscle cells, and the regulation of nerve impulse conduction. The average calcium level in the blood is about 10 mg/dL. When the body cannot maintain this level, a person will experience hypo or hypercalcemia.
The Parathyroid Glands00:59

The Parathyroid Glands

The two pairs of parathyroid glands embedded within the posterior surface of the thyroid gland are restricted by a dense capsule around them. These glands comprise two distinct cell populations—parathyroid oxyphil and parathyroid principal cells- pivotal in calcium homeostasis.
Oxyphil cells, whose functions remain elusive, emerge during late puberty, adding a layer of complexity to the parathyroid gland's intricacies. In contrast, principal parathyroid cells undertake a vital role by producing...
Graves Disease II: Pathophysiology01:24

Graves Disease II: Pathophysiology

Graves’ disease is an autoimmune disorder characterized by the production of thyroid-stimulating immunoglobulins (TSI) that activate TSH receptors, leading to excessive synthesis and release of thyroid hormones (T3 and T4) and resulting in hyperthyroidism.Among all causes of hyperthyroidism, Graves’ disease is the most common and can happen at any age, though it is more frequent in women. It produces a hypermetabolic state with features such as weight loss, tachycardia, tremor, and heat...
Huntington Disease l: Introduction01:21

Huntington Disease l: Introduction

Huntington disease or HD is a progressive, fatal neurodegenerative disorder inherited in an autosomal dominant pattern.PathophysiologyIt is caused by expansion of the CAG trinucleotide repeat in the HTT gene on chromosome 4 (4p16.3), producing an abnormal huntingtin protein with an expanded polyglutamine tract. This misfolded protein disrupts cellular function, leading to neuronal death. Normal alleles have ≤26 repeats, 27–35 are intermediate (risk of expansion), 36–39 show reduced penetrance,...
Dementia l: Introduction01:22

Dementia l: Introduction

Dementia is an acquired, progressive syndrome characterized by a decline in multiple cognitive domains severe enough to impair daily functioning and reduce independence. Although memory loss is a central feature, the diagnosis requires additional deficits involving language, executive function, visuospatial skills, judgment, calculation, or abstract reasoning. These cognitive impairments reflect underlying neurodegenerative or vascular processes that gradually disrupt neuronal networks...
Chronic Pancreatitis I: Introduction01:25

Chronic Pancreatitis I: Introduction

Chronic pancreatitis is a long-standing, relapsing inflammation of the pancreas, characterized by irreversible damage to the gland. It results in progressive destruction of the pancreatic parenchyma, fibrosis, and eventual loss of both exocrine and endocrine function. The disease may evolve gradually after multiple episodes of acute pancreatitis or develop independently.EtiologyChronic pancreatitis can arise from a variety of causes:Alcohol use is the leading cause, accounting for 70–80% of...