Primary Sjögren's syndrome with multiple calcifications in parotid 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...

The salivary glands, of which there are three pairs known as the parotid, submandibular, and sublingual glands, play a crucial role in maintaining oral health and initiating the digestive process. Positioned near the ears, beneath the masseter muscle, the parotid glands secrete saliva into the oral cavity through the parotid duct of Stensen. Meanwhile, the submandibular glands, located on the floor of the mouth, secrete saliva through channels named submandibular ducts. The sublingual glands,...

A sebaceous gland is a type of oil gland found almost all over the skin ( except palms and soles) and helps lubricate and waterproof the skin and hair. Most sebaceous glands are associated with hair follicles. They generate and excrete sebum, a mixture of lipids, onto the skin surface, thereby naturally lubricating the dry and dead layer of keratinized cells of the stratum corneum, keeping it pliable.
These glands that produce the oils on the skin and hair are holocrine glands. The mature...

Secondary organs, including lymph nodes, the spleen, and mucosa-associated lymphoid tissue (MALT), work harmoniously to protect us from disease and infection.
The spleen is a vital organ in the lymphatic system, nestled in the upper left side of the abdomen. It is composed of two primary regions: the red pulp and the white pulp, each having distinct functions. The red pulp performs a significant role in blood filtration. It efficiently purges the blood of old or damaged red blood cells and...

Calcitonin, a vital polypeptide hormone, regulates calcium levels within body fluids. It is released by the parafollicular cells, also known as C cells, situated in the follicular epithelium of the thyroid gland. Calcitonin responds to fluctuations in blood calcium levels and the influence of gastrointestinal hormones like gastrin and cholecystokinin.
The exact mechanisms by which calcitonin operates in calcium homeostasis remain elusive, but its significance is evident in several vital...

The thyroid gland is a small, butterfly-shaped gland located in the neck and covers the anterior surface of the trachea. The gland has two lateral lobes connected by a thin tissue mass called the isthmus. Internally, each lobe comprises many small spherical structures known as thyroid follicles, surrounded by a network of blood vessels.
The follicles have a central cavity lined by simple cuboidal to squamous epithelial cells called follicular cells. These cells produce the glycoprotein...