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61-425: Graft-versus-host disease ( GvHD ) is a syndrome , characterized by inflammation in different organs. GvHD is commonly associated with bone marrow transplants and stem cell transplants . White blood cells of the donor's immune system which remain within the donated tissue (the graft) recognize the recipient (the host) as foreign (non-self). The white blood cells present within the transplanted tissue then attack

122-415: A blood transfusion , known as Transfusion-associated graft-versus-host disease or TA-GvHD if the blood products used have not been gamma irradiated or treated with an approved leukocyte reduction system. In contrast to organ/tissue transplant associated GvHD, the incidence of TA-GvHD is increased with HLA matching (first-degree or close relatives). In the clinical setting, graft-versus-host disease

183-704: A phase 2 clinical trial on 241 children with acute Graft-versus-host disease, that was not responsive to steroids. The trial was of a mesenchymal stem cell therapy known as remestemcel-L or MSC-100-IV. Survival rate was 82% (vs 39% of controls) for those who showed some improvement after one month, and in the long term 72% (vs 18% of controls) for those that showed little effect after one month. Graft-versus-host disease has been implicated in eliminating several cases of HIV, including The Berlin Patient and six others in Spain. Syndrome If an underlying genetic cause

244-436: A " psychosis ", and described "the three major psychoses" as schizophrenia, epilepsy, and manic-depressive illness . In the field of medical genetics, the term "syndrome" is traditionally only used when the underlying genetic cause is known. Thus, trisomy 21 is commonly known as Down syndrome. Until 2005, CHARGE syndrome was most frequently referred to as "CHARGE association". When the major causative gene ( CHD7 ) for

305-429: A mouth and a one-way gut. Some modern invertebrates still have such a system: food being ingested through the mouth, partially broken down by enzymes secreted in the gut, and the resulting particles engulfed by the other cells in the gut lining. Indigestible waste is ejected through the mouth. In animals at least as complex as an earthworm , the embryo forms a dent on one side, the blastopore , which deepens to become

366-407: A nasofrontal hinge allowing the beak to open wider than would otherwise be possible. The exterior surface of beaks is composed of a thin, horny sheath of keratin . Nectar feeders such as hummingbirds have specially adapted brushy tongues for sucking up nectar from flowers. In mammals, the buccal cavity is typically roofed by the hard and soft palates , floored by the tongue and surrounded by

427-458: A range of mouthparts suited to their mode of feeding. These include mandibles, maxillae and labium and can be modified into suitable appendages for chewing, cutting, piercing, sponging and sucking. Decapods have six pairs of mouth appendages, one pair of mandibles, two pairs of maxillae and three of maxillipeds . Sea urchins have a set of five sharp calcareous plates, which are used as jaws and are known as Aristotle's lantern . In vertebrates,

488-483: A rash, burning, and redness of the skin on the palms and soles. This can spread over the entire body. Other symptoms can include nausea, vomiting, stomach cramps, diarrhea (watery and sometimes bloody), loss of appetite, jaundice, abdominal pain, and weight loss. Acute GvHD of the GI tract can result in severe intestinal inflammation, sloughing of the mucosal membrane, severe diarrhea, abdominal pain, nausea, and vomiting. This

549-603: A subset of all medical syndromes. Early texts by physicians noted the symptoms of various maladies and introduced diagnoses based upon those symptoms. For example, Avicenna 's The Canon of Medicine (1025) describes diagnosing pleurisy by its symptoms, including chronic fever, cough, shooting pains, and labored breathing. The 17th century doctor Thomas Sydenham likewise approached diagnoses based upon collections of symptoms. Psychiatric syndromes often called psychopathological syndromes ( psychopathology refers both to psychic dysfunctions occurring in mental disorders , and

610-550: A two-opening gut tube with a mouth at one end and an anus at the other. Which end forms first in ontogeny is a criterion used to classify bilaterian animals into protostomes and deuterostomes . In the first multicellular animals , there was probably no mouth or gut and food particles were engulfed by the cells on the exterior surface by a process known as endocytosis . The particles became enclosed in vacuoles into which enzymes were secreted and digestion took place intracellularly . The digestive products were absorbed into

671-469: Is because the malignant thymus is incapable of appropriately educating developing thymocytes to eliminate self-reactive T cells. The result is a disease virtually indistinguishable from GvHD. The pathophysiology of GvHD includes three phases: Activation of APC occurs in the first stage of GvHD. Prior to haematopoietic stem cell transplantation, radiation or chemotherapy results in damage and activation of host tissues, especially intestinal mucosa. This allows

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732-449: Is commonly a rash on the palms of the hands or the soles of the feet, and the rash can spread and is usually itchy and dry. In severe cases, the skin may blister and peel, like a bad sunburn. A fever may also develop. Other symptoms of chronic GVHD can include: In the oral cavity , chronic graft-versus-host disease manifests as lichen planus with a higher risk of malignant transformation to oral squamous cell carcinoma in comparison to

793-442: Is divided into acute and chronic forms, and scored or graded on the basis of the tissue affected and the severity of the reaction. In the classical sense, acute graft-versus-host disease is characterized by selective damage to the liver , skin (rash), mucosa , and the gastrointestinal tract . Newer research indicates that other graft-versus-host disease target organs include the immune system (the hematopoietic system , e.g.,

854-408: Is partially explained by the fact that the indication itself, that is, complete DiGeorge syndrome , increases the risk of autoimmune disease. A GvHD-like disease called thymoma-associated multiorgan autoimmunity (TAMA) can occur in patients with thymoma. In these patients rather than a donor being a source of pathogenic T cells, the patient's own malignant thymus produces self-directed T cells. This

915-459: Is rare in modern medicine. It is almost entirely preventable by controlled irradiation of blood products to inactivate the white blood cells (including lymphocytes) within. Thymus transplantation may be said to be able to cause a special type of GvHD because the recipient's thymocytes would use the donor thymus cells as models when going through the negative selection to recognize self-antigens, and could therefore still mistake own structures in

976-554: Is severe and requires intense immunosuppression involving steroids and additional agents to get under control, the patient may develop severe infections as a result of the immunosuppression and may die of infection. However, a 2016 study found that the prognosis for patients with grade IV GvHD has improved in recent years. The chronic form of graft-versus-host disease (cGvHD) normally begins 90 to 600 days post-transplant. The appearance of moderate to severe cases of cGVHD adversely influences long-term survival. The first symptom of cGvHD

1037-401: Is suspected but not known, a condition may be referred to as a genetic association (often just "association" in context). By definition, an association indicates that the collection of signs and symptoms occurs in combination more frequently than would be likely by chance alone . Syndromes are often named after the physician or group of physicians that discovered them or initially described

1098-454: Is typically diagnosed via intestinal biopsy. Liver GvHD is measured by the bilirubin level in acute patients. Skin GvHD results in a diffuse red maculopapular rash , sometimes in a lacy pattern. Acute GvHD is staged as follows: overall grade (skin-liver-gut) with each organ staged individually from a low of 1 to a high of 4. Patients with grade IV GvHD usually have a poor prognosis. If the GvHD

1159-445: The archenteron , the first phase in the formation of the gut . In deuterostomes, the blastopore becomes the anus while the gut eventually tunnels through to make another opening, which forms the mouth. In the protostomes, it used to be thought that the blastopore formed the mouth ( proto– meaning "first") while the anus formed later as an opening made by the other end of the gut. More recent research, however, shows that in protostomes

1220-582: The bone marrow and the thymus ) itself, and the lungs in the form of immune-mediated pneumonitis . Biomarkers can be used to identify specific causes of GvHD, such as elafin in the skin. Chronic graft-versus-host disease also attacks the above organs, but over its long-term course can also cause damage to the connective tissue and exocrine glands . Mucosal damage to the vagina can result in severe pain and scarring , and appears in both acute and chronic GvHD. This can result in an inability to have sexual intercourse . The acute or fulminant form of

1281-466: The cheeks , salivary glands , and upper and lower teeth . The upper teeth are embedded in the upper jaw and the lower teeth in the lower jaw , which articulates with the temporal bones of the skull . The lips are soft and fleshy folds which shape the entrance into the mouth. The buccal cavity empties through the pharynx into the oesophagus . Crocodilians living in the tropics can gape with their mouths to provide cooling by evaporation from

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1342-707: The oral cavity (or cavum oris in Latin ), is also the first part of the alimentary canal , which leads to the pharynx and the gullet . In tetrapod vertebrates , the mouth is bounded on the outside by the lips and cheeks — thus the oral cavity is also known as the buccal cavity (from Latin bucca , meaning "cheek") — and contains the tongue on the inside. Except for some groups like birds and lissamphibians , vertebrates usually have teeth in their mouths, although some fish species have pharyngeal teeth instead of oral teeth. Most bilaterian phyla , including arthropods , molluscs and chordates , have

1403-407: The airflow from the lungs in different ways and changes the mouth's resonating properties, producing a range of different sounds. In frogs, the sounds can be amplified using sacs in the throat region. The vocal sacs can be inflated and deflated and act as resonators to transfer the sound to the outside world. A bird's song is produced by the flow of air over a vocal organ at the base of the trachea ,

1464-547: The cavity and it can gape widely enough to accommodate large prey items. Food passes first into a pharynx and digestion occurs extracellularly in the gastrovascular cavity . Annelids have simple tube-like guts, and the possession of an anus allows them to separate the digestion of their foodstuffs from the absorption of the nutrients. Many molluscs have a radula , which is used to scrape microscopic particles off surfaces. In invertebrates with hard exoskeletons, various mouthparts may be involved in feeding behaviour. Insects have

1525-510: The classical oral lichen planus. Oral cancer associated with graft-versus-host disease may have more aggressive behavior with poorer prognosis, when compared to oral cancer in non-hematopoietic stem cell transplantation patients. Three criteria, known as the Billingham criteria, must be met in order for GvHD to occur. After bone marrow transplantation, T cells present in the graft , either as contaminants or intentionally introduced into

1586-489: The condition was discovered, the name was changed. The consensus underlying cause of VACTERL association has not been determined, and thus it is not commonly referred to as a "syndrome". In biology, "syndrome" is used in a more general sense to describe characteristic sets of features in various contexts. Examples include behavioral syndromes , as well as pollination syndromes and seed dispersal syndromes . In orbital mechanics and astronomy, Kessler syndrome refers to

1647-566: The cytoplasm and diffused into other cells. This form of digestion is used nowadays by simple organisms such as Amoeba and Paramecium and also by sponges which, despite their large size, have no mouth or gut and capture their food by endocytosis. However, most animals have a mouth and a gut, the lining of which is continuous with the epithelial cells on the surface of the body. A few animals which live parasitically originally had guts but have secondarily lost these structures. The original gut of diploblastic animals probably consisted of

1708-413: The defining of congenital syndromes that may include birth defects (pathoanatomy), dysmetabolism (pathophysiology), and neurodevelopmental disorders . When there are a number of symptoms suggesting a particular disease or condition but does not meet the defined criteria used to make a diagnosis of that disease or condition. This can be a bit subjective because it is ultimately up to the clinician to make

1769-412: The described symptoms. Signs and symptoms Syndrome Disease Medical diagnosis Differential diagnosis Prognosis Acute Chronic Cure Eponymous disease Acronym or abbreviation Remission Oral cavity The mouth is the body orifice through which many animals ingest food and vocalize . The body cavity immediately behind the mouth opening, known as

1830-513: The desirable graft-versus-tumor effect. This type of GvHD is associated with transfusion of un-irradiated blood to immunocompromised recipients. It can also occur in situations in which the blood donor is homozygous and the recipient is heterozygous for an HLA haplotype . It is associated with higher mortality (80–90%) due to involvement of bone marrow lymphoid tissue, however the clinical manifestations are similar to GVHD resulting from bone marrow transplantation. Transfusion-associated GvHD

1891-406: The diagnosis. This could be because it has not advanced to the level or passed a threshold or just similar symptoms cause by other issues. Subclinical is synonymous since one of its definitions is "where some criteria are met but not enough to achieve clinical status"; but subclinical is not always interchangeable since it can also mean "not detectable or producing effects that are not detectable by

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1952-430: The disease (aGvHD) is normally observed within the first 10 to 100 days post-transplant, and is a major challenge to transplants owing to associated morbidity and mortality. About one-third to one-half of allogeneic transplant recipients will develop acute GvHD. It is less common in younger patients and in those with closer human leukocyte antigens (HLA) matches between donor and the patient. The first signs are usually

2013-597: The donors. HLA-identical siblings or HLA-identical unrelated donors often have genetically different proteins (called minor histocompatibility antigens ) that can be presented by major histocompatibility complex (MHC) molecules to the donor's T-cells, which see these antigens as foreign and so mount an immune response. Antigens most responsible for graft loss are HLA-DR (first six months), HLA-B (first two years), and HLA-A (long-term survival). While donor T-cells are undesirable as effector cells of graft-versus-host disease, they are valuable for engraftment by preventing

2074-475: The edges of the slit-like blastopore close up in the middle, leaving openings at both ends that become the mouth and anus. Apart from sponges and placozoans , almost all animals have an internal gut cavity, which is lined with gastrodermal cells. In less advanced invertebrates such as the sea anemone , the mouth also acts as an anus. Circular muscles around the mouth are able to relax or contract in order to open or close it. A fringe of tentacles thrusts food into

2135-428: The effect where the density of objects in low Earth orbit (LEO) is high enough that collisions between objects could cause a cascade in which each collision generates space debris that increases the likelihood of further collisions. In quantum error correction theory syndromes correspond to errors in code words which are determined with syndrome measurements, which only collapse the state on an error state, so that

2196-407: The error can be corrected without affecting the quantum information stored in the code words. There is no set common convention for the naming of newly identified syndromes. In the past, syndromes were often named after the physician or scientist who identified and described the condition in an initial publication. These are referred to as "eponymous syndromes". In some cases, diseases are named after

2257-474: The expansion of CD8 + and CD4 + T-cells and guest B-cells. In the final phase, these effector cells migrate to target organs and mediate tissue damage, resulting in multiorgan failure. Intravenously administered glucocorticoids , such as prednisone , are the standard of care in acute GvHD and chronic GVHD. The use of these glucocorticoids is designed to suppress the T-cell-mediated immune onslaught on

2318-489: The first line of treatment for acute GVHD, only about 50% of patients respond to treatment, otherwise having steroid-refractory GVHD (SR-GVHD). An increasing number of recent treatment options for SR-GVHD have been investigated, such as extracorporeal photopheresis (ECP), mesenchymal stem cell (MSCs), fecal microbial transplantation (FMT), and the medication Ruxolitinib. Cyclosporine and tacrolimus are calcineurin inhibitors . The substances are structurally different but have

2379-473: The first part of the digestive system is the buccal cavity , commonly known as the mouth. The buccal cavity of a fish is separated from the opercular cavity by the gills . Water flows in through the mouth, passes over the gills and exits via the operculum or gill slits . Nearly all fish have jaws and may seize food with them but most feed by opening their jaws, expanding their pharynx and sucking in food items. The food may be held or chewed by teeth located in

2440-654: The full clinical picture. Such eponymous syndrome names are examples of medical eponyms . Recently, there has been a shift towards naming conditions descriptively (by symptoms or underlying cause) rather than eponymously, but the eponymous syndrome names often persist in common usage. The defining of syndromes has sometimes been termed syndromology, but it is usually not a separate discipline from nosology and differential diagnosis generally, which inherently involve pattern recognition (both sentient and automated ) and differentiation among overlapping sets of signs and symptoms. Teratology (dysmorphology) by its nature involves

2501-458: The host tissues; however, in high doses, this immune-suppression raises the risk of infections and cancer relapse. Therefore, it is desirable to taper off the post-transplant high-level steroid doses to lower levels, at which point the appearance of mild GVHD may be welcome, especially in HLA mis-matched patients, as it is typically associated with a graft-versus-tumor effect..While glucocorticoids remain

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2562-412: The host, attack the tissues of the transplant recipient after perceiving host tissues as antigenically foreign. The T cells produce an excess of cytokines , including TNF-α and interferon-gamma (IFNγ). A wide range of host antigens can initiate graft-versus-host disease, among them the human leukocyte antigens (HLA). However, graft-versus-host disease can occur even when HLA-identical siblings are

2623-410: The investigation of graft-versus-host disease treatment and prevention. On 17 May 2012, Osiris Therapeutics announced that Canadian health regulators approved Prochymal , its drug for acute graft-versus-host disease in children who have failed to respond to steroid treatment. Prochymal is the first stem cell drug to be approved for a systemic disease. In January 2016, Mesoblast released results of

2684-433: The jaws, on the roof of the mouth, on the pharynx or on the gill arches . Nearly all amphibians are carnivorous as adults. Many catch their prey by flicking out an elongated tongue with a sticky tip and drawing it back into the mouth, where they hold the prey with their jaws. They then swallow their food whole without much chewing. They typically have many small hinged pedicellate teeth , the bases of which are attached to

2745-755: The jaws, while the crowns break off at intervals and are replaced. Most amphibians have one or two rows of teeth in both jaws but some frogs lack teeth in the lower jaw. In many amphibians, there are also vomerine teeth attached to the bone in the roof of the mouth. The mouths of reptiles are largely similar to those of mammals. The crocodilians are the only reptiles to have teeth anchored in sockets in their jaws. They are able to replace each of their approximately 80 teeth up to 50 times during their lives. Most reptiles are either carnivorous or insectivorous, but turtles are often herbivorous. Lacking teeth that are suitable for efficiently chewing of their food, turtles often have gastroliths in their stomach to further grind

2806-405: The mechanism for producing sounds for communication. To produce sounds, air is forced from the lungs over vocal cords in the larynx. In humans, the pharynx, soft palate, hard palate, alveolar ridge , tongue, teeth and lips are termed articulators and play their part in the production of speech . Varying the position of the tongue in relation to the other articulators or moving the lips restricts

2867-430: The microbial products to enter and stimulate pro-inflammatory cytokines such as IL-1 and TNF-α . These proinflammatory cytokines increase the expression of MHC and adhesion molecules on APCs, thereby increasing the ability of APC to present antigen. The second phase is characterized by the activation of effector cells. Activation of donor T-cells further enhances the expression of MHC and adhesion molecules, chemokines and

2928-465: The mild disorders, consists of five syndromes: emotional, paranoid, hysterical , delirious , and impulsive. The second, intermediate, group includes two syndromes: schizophrenic syndrome and speech-hallucinatory syndrome . The third includes the most severe disorders, and consists of three syndromes: epileptic , oligophrenic and dementia . In Kraepelin's era, epilepsy was viewed as a mental illness; Karl Jaspers also considered "genuine epilepsy"

2989-419: The mouth lining. Some mammals rely on panting for thermoregulation as it increases evaporation of water across the moist surfaces of the lungs, the tongue and mouth. Birds also avoid overheating by gular fluttering, flapping the wings near the gular (throat) skin, similar to panting in mammals. Various animals use their mouths in threat displays. They may gape widely, exhibit their teeth prominently, or flash

3050-481: The non-possessive form, while European references often use the possessive. A 2009 study demonstrated a trend away from the possessive form in Europe in medical literature from 1970 through 2008. Even in syndromes with no known etiology , the presence of the associated symptoms with a statistically improbable correlation normally leads the researchers to hypothesize that there exists an unknown underlying cause for all

3111-448: The patient who initially presents with symptoms, or their home town ( Stockholm syndrome ). There have been isolated cases of patients being eager to have their syndromes named after them, while their physicians are hesitant. When a syndrome is named after a person, there is some difference of opinion as to whether it should take the possessive form or not (e.g. Down syndrome vs. Down's syndrome). North American usage has tended to favor

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3172-517: The plant material. Snakes have a very flexible lower jaw, the two halves of which are not rigidly attached, and numerous other joints in their skull. These modifications allow them to open their mouths wide enough to swallow their prey whole, even if it is wider than they are. Birds do not have teeth, relying instead on other means of gripping and macerating their food. Their beaks have a range of sizes and shapes according to their diet and are composed of elongated mandibles. The upper mandible may have

3233-414: The recipient's body's cells, which leads to GvHD. This should not be confused with a transplant rejection , which occurs when the immune system of the transplant recipient rejects the transplanted tissue; GvHD occurs when the donor's immune system's white blood cells reject the recipient. The underlying principle ( alloimmunity ) is the same, but the details and course may differ. GvHD can also occur after

3294-455: The recipient's residual immune system from rejecting the bone marrow graft ( host-versus-graft ). In addition, as bone marrow transplantation is frequently used to treat cancer , mainly leukemias , donor T-cells have proven to have a valuable graft-versus- tumor effect. A great deal of current research on allogeneic bone marrow transplantation involves attempts to separate the undesirable graft-vs-host disease aspects of T-cell physiology from

3355-514: The rest of the body for being non-self. This is a rather indirect GvHD because it is not directly cells in the graft itself that causes it but cells in the graft that make the recipient's T cells act like donor T cells. It can be seen as a multiple-organ autoimmunity in xenotransplantation experiments of the thymus between different species. Autoimmune disease is a frequent complication after human allogeneic thymus transplantation, found in 42% of subjects over one year post-transplantation. However, this

3416-412: The same mechanism of action. Cyclosporine binds to the cytosolic protein peptidyl-prolyl cis-trans isomerase A (known as cyclophilin), while tacrolimus binds to the cytosolic protein peptidyl-prolyl cis-trans isomerase FKBP12. These complexes inhibit calcineurin, block dephosphorylation of the transcription factor NFAT of activated T-cells and its translocation into the nucleus. Standard prophylaxis involves

3477-419: The startling colours of the mouth lining. This display allows each potential combatant an opportunity to assess the weapons of their opponent and lessens the likelihood of actual combat being necessary. A number of species of bird use a gaping , open beak in their fear and threat displays. Some augment the display by hissing or breathing heavily, while others clap their beaks. Mouths are also used as part of

3538-1676: The study of the origin, diagnosis, development, and treatment of mental disorders). In Russia those psychopathological syndromes are used in modern clinical practice and described in psychiatric literature in the details: asthenic syndrome , obsessive syndrome , emotional syndromes (for example, manic syndrome , depressive syndrome), Cotard's syndrome , catatonic syndrome , hebephrenic syndrome, delusional and hallucinatory syndromes (for example, paranoid syndrome, paranoid-hallucinatory syndrome, Kandinsky - Clérambault's syndrome also known as syndrome of psychic automatism, hallucinosis), paraphrenic syndrome , psychopathic syndromes (includes all personality disorders), clouding of consciousness syndromes (for example, twilight clouding of consciousness, amential syndrome also known as amentia, delirious syndrome , stunned consciousness syndrome, oneiroid syndrome ), hysteric syndrome, neurotic syndrome , Korsakoff's syndrome , hypochondriacal syndrome , paranoiac syndrome, senestopathic syndrome, encephalopathic syndrome . Some examples of psychopathological syndromes used in modern Germany are psychoorganic syndrome , depressive syndrome, paranoid-hallucinatory syndrome, obsessive-compulsive syndrome , autonomic syndrome, hostility syndrome, manic syndrome , apathy syndrome . Münchausen syndrome , Ganser syndrome , neuroleptic-induced deficit syndrome , olfactory reference syndrome are also well-known. The most important psychopathological syndromes were classified into three groups ranked in order of severity by German psychiatrist Emil Kraepelin (1856—1926). The first group, which includes

3599-471: The use of cyclosporine for six months with methotrexate. Cyclosporin levels should be maintained above 200 ng/ml. Other substances that have been studied for GvHD treatment include, for example: sirolimus , pentostatin , etanercept , and alemtuzumab . In August 2017, the US FDA approved ibrutinib to treat chronic GvHD after failure of one or more other systemic treatments. Axatilimab (Niktimvo)

3660-427: The usual clinical tests"; i.e., asymptomatic. In medicine, a broad definition of syndrome is used, which describes a collection of symptoms and findings without necessarily tying them to a single identifiable pathogenesis. Examples of infectious syndromes include encephalitis and hepatitis , which can both have several different infectious causes. The more specific definition employed in medical genetics describes

3721-581: Was approved for medical use in the United States in August 2024. Given the complex systemic condition and immunosuppression of the chronic GVHD patients, non-drug therapies, are a significant advancement, and may be preferred whenever possible. Examples are photobiomodulation for GVHD-related oral mucosal ulcers , and electrostimulation for GVHD-related xerostomia . There are a large number of clinical trials either ongoing or recently completed in

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