Encyclopedia
Scholarly Community
Encyclopedia
Entry
Video
Image
Journal
Book
News
About
Entry
Entry
Video
Image
Log in/Sign up
Submit
Entry
Video
Image
Subject:
All Disciplines
Arts & Humanities
Biology & Life Sciences
Business & Economics
Chemistry & Materials Science
Computer Science & Mathematics
Engineering
Environmental & Earth Sciences
Medicine & Pharmacology
Physical Sciences
Public Health & Healthcare
Social Sciences
Sort:
Hottest
Latest
Alphabetical (A-Z)
Alphabetical (Z-A)
Type:
All
Topic Review
Biography
Topic Review
Tuberculosis IRIS
Antiretroviral therapy (ART), while essential in combatting tuberculosis (TB) and HIV coinfection, is often complicated by TB-associated immune reconstitution inflammatory syndrome (TB-IRIS). Depending on the TB diagnosis and treatment status at ART initiation, this immune-mediated worsening of TB pathology can take the form of paradoxical TB-IRIS, unmasking TB-IRIS. Each form of TB-IRIS has unique implications for diagnosis and treatment. This entry is a discussion of TB-IRIS with an expanded focus on CNS TB-IRIS given its severe outcomes and anatomic and immunologic peculiarities.
821
06 Nov 2020
Topic Review
Tuberculosis Disease
Tuberculosis disease is caused by the bacterium Mycobacterium tuberculosis. It is estimated that 10 million people have developed tuberculosis disease globally, leading to 1.4 million deaths in 2019. Treatment of tuberculosis has been especially challenging due to the rise of multidrug-resistant (MDR-TB) and extensive drug-resistant (XDR-TB) tuberculosis. In addition to drug-resistant genotypes, the standard treatment of tuberculosis by first-line agents is also challenging due to toxicity and costs.
373
27 Dec 2021
Topic Review
Tuberculosis and Autoimmunity
It is long-established that pathogenesis of many autoimmune diseases is mainly promoted by inadequate immune responses to bacterial agents, among them Mycobacterium tuberculosis. Tuberculosis is a multifaceted process having many different outcomes and complications. Autoimmunity is one of the processes characteristic of tuberculosis; the presence of autoantibodies was documented by a large amount of evidence. The role of autoantibodies in pathogenesis of tuberculosis is not quite clear and widely disputed. They are regarded as: (1) a result of imbalanced immune response being reactive in nature, (2) a critical part of TB pathogenicity, (3) a beginning of autoimmune disease, (4) a protective mechanism helping to eliminate microbes and infected cells, and (5) playing dual role, pathogenic and protective. There is no single autoimmunity-mechanism development in tuberculosis; different pathways may be suggested. It may be excessive cell death and insufficient clearance of dead cells, impaired autophagy, enhanced activation of macrophages and dendritic cells, environmental influences such as vitamin D insufficiency, and genetic polymorphism, both of Mycobacterium tuberculosis and host.
407
19 Sep 2022
Topic Review
Tuberculin
Tuberculin, also known as purified protein derivative, is a combination of proteins that are used in the diagnosis of tuberculosis. This use is referred to as the tuberculin skin test and is recommended only for those at high risk. Reliable administration of the skin test requires large amounts of training, supervision, and practice. Injection is done into the skin. After 48 to 72 hours, if there is more than a five to ten millimeter area of swelling, the test is considered positive. Common side effects include redness, itchiness, and pain at the site of injection. Allergic reactions may occasionally occur. The test may be falsely positive in those who have been previously vaccinated with BCG or have been infected by other types of mycobacteria. The test may be falsely negative within ten weeks of infection, in those less than six months old, and in those who have been infected for many years. Use is safe in pregnancy. Tuberculin was discovered in 1890 by Robert Koch. Koch, best known for his work on the etiology of tuberculosis (TB), laid down various rigorous guidelines that aided the establishment between a pathogen and the specific disease that followed that were later named Koch's postulates. Although he initially believed it would cure tuberculosis, this was later disproved. Tuberculin is made from an extract of Mycobacterium tuberculosis. It is on the World Health Organization's List of Essential Medicines.
792
29 Sep 2022
Topic Review
Tubal Endometriosis
Tubal endometriosis (EM) refers to the detection of ectopic endometrial implants on tubes. It may cause a significant defect of the tubes, translating into dysmenorrhea, pelvic pain, and infertility.
446
08 Mar 2022
Topic Review
TSPAN8
Tetraspanin 8 (TSPAN8) is a member of the tetraspanin superfamily that forms TSPAN8-mediated protein complexes by interacting with themselves and other various cellular signaling molecules. These protein complexes help build tetraspanin-enriched microdomains (TEMs) that efficiently mediate intracellular signal transduction. In physiological conditions, TSPAN8 plays a vital role in the regulation of biological functions, including leukocyte trafficking, angiogenesis and wound repair. Recently, reports have increasingly shown the functional role and clinical relevance of TSPAN8 overexpression in the progression and metastasis of several cancers.
630
15 Jun 2021
Topic Review
Tryptophan Metabolism in Cardiovascular Diseases
Cardiovascular disease (CVD) is one of the major causes of mortality worldwide. Inflammation is the underlying common mechanism involved in CVD. It has been recently related to amino acid metabolism, which acts as a critical regulator of innate and adaptive immune responses. Among different metabolites that have emerged as important regulators of immune and inflammatory responses, tryptophan (Trp) metabolites have been shown to play a pivotal role in CVD.
1.1K
13 Oct 2021
Topic Review
Tryptophan Metabolism
Tryptophan metabolism, via the kynurenine (Kyn) pathway, and microbial transformation of tryptophan to indolic compounds are fundamental for host health; both of which are altered in colon carcinogenesis.
1.2K
07 May 2021
Topic Review
Tryptophan Metabolic Pathways in Migraine-Related Mechanisms
Migraine is a complex neurovascular disorder, which causes intense socioeconomic problems worldwide. The pathophysiology of disease is enigmatic; accordingly, therapy is not sufficient. Migraine research focused on tryptophan, which is metabolized via two main pathways, the serotonin and kynurenine pathways. Both produce neuroactive molecules that influence pain processing and stress response by disturbing neural and brain hypersensitivity and interacting with molecules that control vascular and inflammatory actions. Serotonin has a role in trigeminal pain processing, and melatonin, another product of this pathway, also has a role in these processes. One of the end products of the kynurenine pathway is kynurenic acid (KYNA), which can decrease the overexpression of migraine-related neuropeptides in experimental conditions. However, the ability of KYNA to cross the blood-brain barrier is minimal, necessitating the development of synthetic analogs with potentially better pharmacokinetic properties to exploit its therapeutic potential.
1.1K
05 Dec 2022
Topic Review
Tryptophan Dysmetabolism and Quinolinic Acid in Neurodegenerative Diseases
Evidence suggests that neuroinflammation is involved in both depression and neurodegenerative diseases. The kynurenine pathway, generating metabolites which may play a role in pathogenesis, is one of several competing pathways of tryptophan metabolism. A disturbed tryptophan metabolism with increased activity of the kynurenine pathway and production of quinolinic acid may result in deficiencies in tryptophan and derived neurotransmitters. Quinolinic acid is an N-methyl-D-aspartate receptor agonist, and raised levels in CSF, together with increased levels of inflammatory cytokines, have been reported in mood disorders. Increased quinolinic acid has also been observed in neurodegenerative diseases, including Parkinson’s disease, Alzheimer’s disease, amyotrophic lateral sclerosis, and HIV-related cognitive decline.
828
29 Jul 2022
Page
of
1349
Featured Entry Collections
>>
Featured Books
>>
Encyclopedia of Social Sciences
Chief Editor:
Michael McAleer
Encyclopedia of COVID-19
Chief Editor:
Stephen Bustin
Encyclopedia of Fungi
Chief Editor:
Luis V. Lopez-Llorca
Encyclopedia of Digital Society, Industry 5.0 and Smart City
Chief Editor:
Sandro Serpa
Entry
Video
Image
Journal
Book
News
About
Log in/Sign up
New Entry
New Video
New Images
About
Terms and Conditions
Privacy Policy
Advisory Board
Contact
Partner
Video Production Service
Feedback
Top
Feedback
×
Help Center
Browse our user manual, common Q&A, author guidelines, etc.
Rate your experience
Let us know your experience and what we could improve.
Report an error
Is something wrong? Please let us know!
Other feedback
Other feedback you would like to report.
×
Did you find what you were looking for?
Love
Like
Neutral
Dislike
Hate
0
/500
Email
Do you agree to share your valuable feedback publicly on
Encyclopedia
’s homepage?
Yes, I agree. Encyclopedia can post it.
No, I do not agree. I would not like to post my testimonial.
Webpage
Upload a screenshot
(Max file size 2MB)
Submit
Back
Close
×