The electrochemical response of thyroxine (T4) at a carbon paste electrode (CPE) in the presence of cetyltrimethylammonium bromide (CTAB) was investigated. It gave a well-defined oxidation peak at 0.80 V and a sensitive reduction peak at 0.40 V. Compared with the indiscernible signal in the absence of CTAB, the reduction current of T4 at CPE was greatly enhanced in the presence of CTAB, due to ...

background: levothyroxine is commonly used in the treatment of patients with hypothyroidism. levothyroxine is often administered in the morning, on an empty stomach, to increase its absorption. however, many patients have trouble for taking levothyroxine in the morning. the aim of this study was to evaluate the effect of changing administration time of levothyroxine from before breakfast to bef...

Thyroxine(T4)-binding to serum proteins in primates; catarrhini, prosimiae, and platyrrhini were studied by polyacrylamide gel electrophoresis T4 binding analysis. From the electrophoretic analysis, it was shown that thyroxine-binding proteins similar to human thyroxine-binding globulin (TBG) and thyroxine-binding prealbumin (TBPA) were present in catarrhini and prosimiae species, but not in pl...

Previous research into T4 bacteriophage infection of E. coli biofilms observed that during the fourth day of biofilm development, a transient substantial increase in T4 phage progeny production occurs. This increase was hypothesized to be due to over-expression of the outer membrane protein C (OmpC). OmpC is used by T4 bacteriophage for binding to the host cell, therefore its over-expression in...

Bacteriophage T4 rnh encodes an RNase H that removes ribopentamer primers from nascent DNA chains during synthesis by the T4 multienzyme replication system in vitro (H. C. Hollingsworth and N. G. Nossal, J. Biol. Chem. 266:1888-1897, 1991). This paper demonstrates that either T4 RNase HI or Escherichia coli DNA polymerase I (Pol I) is essential for phage replication. Wild-type T4 phage producti...

The main objective of this study was to characterize nuclear T3 and T4 binding in the developing rat brain. More specifically, we sought to determine (a) whether T3 and T4 bind to the same nuclear receptor, (b) whether there are multiple forms of nuclear T3 or T4 receptors, and (c) whether the above parameters are similar in nuclei of cerebral hemispheres and cerebellum of developing rat brain....

Thyroid hormones exert a profound effect on development, growth, and metabolism of skeleton. In the present study, we evaluated the effects of thyroxine (T4) and growth hormone (GH) on the terminal differentiation of rib growth plate chondrocytes in three-dimensional pellet culture. T4 (30ng/ml) stimulated the expressions of type II and X collagens, alkaline phosphatase (ALP) activity. On the o...

The Amerlex Free Thyroxin (T4) Radioimmunoassay Kit (Amersham International Ltd.) is a new direct equilibrium radioimmunoassay for free T4 based on an antiserum with very high affinity for T4, and a unique 125I-labeled T4 analog as tracer. It is a very simple single-tube radioimmunoassay, making use of Amerlex particles to separate antibody-bound from free species. Interassay precision (CV) is ...

The current treatment for patients with hypothyroidism is levothyroxine (L-T4) along with normalization of serum thyroid-stimulating hormone (TSH). However, normalization of serum TSH with L-T4 monotherapy results in relatively low serum 3,5,3'-triiodothyronine (T3) and high serum thyroxine/T3 (T4/T3) ratio. In the hypothalamus-pituitary dyad as well as the rest of the brain, the majority of T3...

Certain temperature-sensitive mutants of gene 42 of bacteriophage T4 increase the reversion rates of some rII mutants in the same genome by about 4 to 10 times. This effect was usually found at 34 C, an intermediate permissive temperature, but not at 28 C.