The Red and White Pulp Cords of the Human Spleen

The red pulp cord, a structural feature in the human ear, consists of interlocked littoral cells composed of bands of reticulum. The white stroma is composed of macrophages and fixed reticular cells. These cells are found in the pulp cord and are also interlocked. The reticulum provides support for the pulp cord.

Red pulp macrophages

Red pulp macrophages are cells found in the splenic cord and are associated with red blood cells and plasma cells. These cells are necessary for blood homeostasis. They phagocytose blood-borne particles and are maintained throughout an individual’s life. The red pulp macrophages on the pulp cord are composed of F4/80+ macrophages.

Macrophages in red pulp cords are not ubiquitous, unlike macrophages in the spleen. Red pulp macrophages may be involved in recycling iron and the turnover of red blood cells. This process is known as erythrophagocytosis and is essential in recycling iron and promoting the metabolism of red blood cells.

Red pulp macrophages may be involved in the defense against malaria infections. They have been implicated in the regeneration of infected erythrocytes and the clearance of blood-borne particulates. However, there is still uncertainty about their exact function in the defense against malaria.

In addition to macrophages, red pulp also contains lymphocytes. These cells are important in innate and adaptive immune responses. They migrate to the pulp cord through CXCR4 and CXCR7, which allow them to enter the central area. They can then pick up antigens and present them to passing T cells.

Littoral cells

Littoral cells are a type of cell found in the pulp cord of the human spleen. These cells contain prominent cytoplasmic filaments and lysosomes. They also have dense deposits surrounding the nucleus. They contain phagocytosed RBCs, leukocytes, and hemosiderin.

Littoral cell angiomas have characteristic immunohistochemical markers and display a hybrid endothelial phenotype. Unlike its lymph node and soft tissue counterpart, littoral cell angiomas are uncommon and multicentric. In addition to the pulp cord, they can involve the pancreas and liver. However, the disseminated disease is rare.

Littoral cell angioma is a rare vascular neoplasm of the pulp cord composed of littoral cells. These cells are usually found in the pulp cord and are believed to play an essential role in the immune response. The vast majority of littoral cell angiomas are benign, though rare cases of malignancy have been reported.

LCs are multi-lineage cells and express a variety of antigens. They are also associated with endothelial and mono/macrophage/dendritic cells. Furthermore, they are highly specialized barrier cells and are a significant component of the human spleen.

Littoral cells are the dominant population of cells in the red pulp of the spleen. These cells are found in the red pulp of man and closely related primates. They are characterized by high FHOD1 expression and are highly vascular. Although they do not exhibit any distinctive nodular pattern, they are characterized by a distinct type of vascular channel.

Fixed reticulum cells

Fixed reticulum cells in the pulp cord form a network of blood vessels. These blood vessels have a characteristic appearance, with open ends CD34+ and CD271+. These vessels are surrounded by the sinus network, which is impeded most of the time. In addition, the capillary sheaths are composed of CD34+ cells and are segmented by brown endothelial cells. In addition, granular blue structures are located on the surface of the trabecula, representing the superficial fibroblasts. Finally, a light brown cover marks irregularities and flat apertures associated with the sectioning.

Reticulum cells are round or oval. They also have pigment granules in their cytoplasm but do not stain deeply with carmine, a characteristic that distinguishes them from Malpighian corpuscles. The spleen also contains macrophages with a single compound nucleus and many PHH3-IR cells.

The spleen’s red pulp cord contains reticular cells and macrophages associated with erythrocytes. These cells have F4/80+ or red pulp macrophages, and blood flows through them into the venous sinuses.

The red pulp spleen contains a network of capillaries. These capillary cells have end processes surrounded by red pulp venules. In this network, the veins have multiple CD34+ methods of variable length and diameter. In contrast, the white pulp cord has a higher density of capillary processes with a more significant number of open capillary ends.

In addition to fibroblastic reticular cells, a three-dimensional network of blood vessels is present. These vessels are located on the inner surface of the splenic cord. The cord also contains a vascular network that feeds the red pulp.

Spongy arterial terminals

The central artery of the spleen passes through both the red and white pulps of the spleen. It has three sections: one that empties into the red pulp and the other two into the sinusoids. These cords contain numerous sheathed arteries. Blood delivered to the lines passes through the elongated cells separated by slits.

The sensory nerves of the pulp are derived from the trigeminal nerve. They pass into the radicular pulp in bundles close to venules and arterioles. The sensory nerves are invested in Schwann cells. After being infused with a myelin sheath, they are located in the central region of the pulp. In young pulp, these fibers are sparse; as the pulp ages, their number increases.

These nerve fibers carry neuropeptides. These neuropeptides are substance P, substance Y, and neurokinin A. These neuropeptides act to activate vascular responses to various external stimuli. Multiple stimuli, including tissue injury, trigger the release of these neuropeptides. These neuropeptides cause vascular changes similar to those induced by histamine and bradykinin.

Standard measuring units for timber and pulpwood

In the United States, timber and pulpwood are measured in cords. A cord contains approximately 90 cubic feet of solid wood. However, the volume varies based on the logs’ size, the bark’s presence, and the stacking method. For example, a cord may contain five saw logs piled four feet high by eight feet long, but the actual volume will vary.

In the Southeast, the softwood trade is divided into three major classes: saw timber, chip-n-saw, and plylogs. Each of these products requires a specific diameter and a certain degree of straightness. The latter two are made from smaller trees, while pulpwood comes from more giant trees. The former is usually harvested from younger trees, while the latter is gathered at an older age.

Unlike most timber products, pulpwood is not measured in yards. The volume is estimated by measuring its diameter and height. A portion of the measurement is subtracted if the tree is shaped like an oval. The total volume is then calculated. This is one of the most reliable methods for measuring timber and pulpwood.

Cords are a standard unit for measuring firewood and pulpwood in the U.S. and Canada. A cord consists of one hundred twenty-six cubic feet of wood. It is approximately equivalent to 3.6 m3. In Canada, cords are measured in cubic meters. In the United States, a cord is equal to 128 cubic feet.

One of the most important considerations when buying wood for pulpwood is the volume. Cords are not necessarily uniform, and you need to know the exact measurements before buying. Purchasing logs in chips is another issue. When purchasing timber and pulpwood in chunks, remember to cut them into squares or rectangles. You can also find a log scale appropriate for the size of the logs in your region.