healing - Healing by regeneration, Healing by repair, Specific examples of healing

Any method by which an illness or injury is cured; specifically, the use of a technique which is not recognized within orthodox medicine and involves no form of physical therapy or manipulation. Techniques such as the ‘laying on of hands’ are seen as involving the transmission of energy from, or channelling through, a healer and into the sick person. Sometimes prayer, visualization, meditation, or other methods are used by the patient, healer, or both to help focus beneficial thoughts and energy onto the illness. Although touch may be used to transmit healing energies, some healers claim to be able to treat their patients from a distance. Controlled studies have shown the beneficial effects of positive thoughts and healing energies directed at bacteria, plants, cancer cells, and even animals such as mice. There are many anecdotal reports of untreatable illnesses being cured, including those which form part of the sacred literature of most major religions.

Healing is the process whereby the cells in the body regenerate and repair to reduce the size of a damaged or necrotic area.

The replacement can happen in two ways:

by regeneration: the necrotic cells are replaced by the same tissue as was originally there.

Healing by regeneration

In order for an injury to be healed by regeneration, the cell type that was destroyed must be able to replicate. Most cells have this ability, although it is believed that cardiac muscle cells and neurons are two important exceptions.

Cells also need a collagen framework along which to grow.

Example of regeneration

Acute tubular necrosis (ATN) in the kidney is a case in which cells heal completely by regeneration. ATN occurs when the epithelial cells that line the kidney are destroyed by either a lack of oxygen (such as in hypovolemic shock, when blood supply to the kidneys is dramatically reduced), or by toxins (such as some antibiotics, heavy metals or carbon tetrachloride).

Although many of these epithelial cells are dead, there is typically patchy necrosis, meaning that there are patches of epithelial cells still alive.

The existing epithelial cells can replicate, and, using the basement membrane as a guide, eventually bring the kidney back to normal.

Healing by repair

Healing must happen by repair in the case of injury to cells that are unable to regenerate (e.g.

Soon after injury, a wound healing cascade is unleashed.

In the inflammatory phase, macrophages and other phagocytic cells kill bacteria, debride damaged tissue and release chemical factors such as growth hormones that encourage fibroblasts epithelial cells and endothelial cells which make new capillaries to migrate to the area and divide.

In the proliferative phase, immature granulation tissue containing plump active fibroblasts and forms.

As granulation tissue matures, the fibroblasts produce less collagen and become more spindly in appearance.

During the maturation phase of wound healing, unnecessary vessels formed in granulation tissue are removed by apoptosis, and type III collagen is largely replaced by type I.

Specific examples of healing

Wound healing - this is important cosmetically and functionally, as scar formation, especially at a joint, can impair movement. Bone healing - the healing of a fracture takes a long time, has many potential problems, and a great deal can be done surgically to overcome these problems. Nerve healing - Even though neurons cannot replicate, a nerve is often just a collection of axons, and the cell itself doesn't die.