University of Texas System

About: University of Texas System is a education organization based out in Austin, Texas, United States. It is known for research contribution in the topics: Cancer & Population. The organization has 13901 authors who have published 10925 publications receiving 319328 citations. The organization is also known as: UT System.

Melatonin in relation to the antioxidative defense and immune systems : possible implications for cell and organ transplantation

Abstract: Melatonin, a molecule synthesized and secreted by the mammalian (including human) pineal gland, has a variety of seemingly unrelated functions in organisms. In photoperiodically-dependent seasonal breeders, the changing melatonin signal imparts seasonal information to the species thereby regulating the annual cycle of reproduction [1]. Melatonin also is involved in a number of 24 h rhythms and is believed to be an important component of the circadian system [2, 3]. More recently, melatonin was found to relate to immune function [4] in organisms and to be an effective antioxidant [5]. As an antioxidant melatonin would appear to provide substantial protection against free radicals which are generated under a variety of experimental corrections, including ischemia/reperfusion injury [6, 7]. These latter two functions of melatonin, i.e., as an immune system modulator and as an antioxidant, both may have applicability to cell and organ transplantation [8–11].

Fusarium. A newly recognized fungal pathogen in immunosuppressed patients.

Abstract: Two cases of disseminated fungal infection due to Fusarium species, that occurred during a 4-month period, are reported. Both patients had a myeloproliferative disorder for which they had received intensive cytotoxic and immunosuppressive therapy, and both died despite treatment with amphotericin B. This report and review of the recent literature suggest that Fusarium is emerging as a newly recognized fungal pathogen in immunosuppressed patients.

Metal complexes of water soluble texaphyrins

Abstract: The present invention involves water soluble hydroxy-substituted texaphyrins retaining lipophilicity, of formula (I) wherein: M is H, a divalent or a trivalent metal cation; R1, R2, R3, R4 and R5 are independently H, OH, C n H(2n+1)O y or OC n H(2n+1)O y where at least one of R1, R2, R3, R4 and R5 has at least one hydroxy substituent; the molecular weight of any one of R1, R2, R3, R4 or R5 is less than or equal to about 1000 daltons; n is a positive integer or zero; y is zero or a positive integer less than or equal to (2n+ 1); and N is an integer between -20 and +2. These expanded porphyrin-like macrocycles are efficient chelators of divalent and trivalent metal ions. Various metal (e.g., transition, main group, and lanthanide) complexes of the hydroxy-substituted texaphyrin derivatives of the present invention have unusual water solubility and stability. They absorb light strongly in a physiologically important region (i.e. 690-880 nm). They have enhanced relaxivity and therefore are useful in magnetic resonance imaging. They form long-lived triplet states in high yield and act as photosensitizers for the generation of singlet oxygen. Thus, they are useful for inactivation or destruction of human immunodeficiency virus (HIV-1), mononuclear or other cells infected with such virus as well as tumor cells. They are water soluble, yet they retain sufficient lipophilicity so as to have greater affinity for lipid rich areas such as atheroma and tumors. They may be used for magnetic resonance imaging followed by photodynamic tumor therapy in the treatment of atheroma and tumors. These properties, coupled with their high chemical stability and appreciable solubility in water, add to their usefulness.