A new clerodane-type diterpenoid, echinoclerodane A (1), was isolated from a Formosan gorgonian coral Echinomuricea sp. The structure of 1 was elucidated by spectroscopic methods. Echinoclerodane A (1) is the first clerodane-type compound obtained from the marine organisms belonging to the phylum Cnidaria. Echinoclerodane A (1) exhibited moderate cytotoxicity toward MOLT-4, HL-60, DLD-1 and LoV...

BACKGROUND Cordycepin requires the relatively toxic co-drug, deoxycoformycin, for full efficacy as an anticancer agent. We sought to improve cordycepin efficacy using other, less toxic co-drugs. MATERIALS AND METHODS We evaluated the ability of hydroxyurea (HU) to enhance the effects of cordycepin against MOLT-4 leukemia cells with the MTT cell viability assay. We determined the relationship ...

Three pregnane-type steroids, including a new metabolite, 3β-methoxy-5,20-pregnadiene (1) along with two known analogues, 3β-acetoxy-5,20-pregnadiene (2) and 5α-pregna-1,20-dien-3-one (3) were isolated from the soft coral Scleronephthya flexilis. Standard spectroscopic techniques were used to determine the structure of new steroid 1. The absolute stereochemistry of steroid 2 was confirmed by X-...

Gamijeonssibaekchulsan (GJBS) is a typical Oriental medicine prescription which has been used in Korea for the treatment of allergic diseases and the development of physical strength. However, as yet there is no clear explanation of how GJBS affects the anaphylactic reaction and the immune function. In the present study murine models and MOLT-4 cells, a T cell line, were used to investigate the...

We have examined the effects of hyperthermia and radiation on the ability of a human T-leukemic lymphocyte line (Molt-4) to transport the Na -dependent amino acid, 2-aminoisobutyrate (AIB). Heating Molt-4 at 43°for 1 to 4 hr damages the ability of these cells to accumulate AIB. The damage to the transport system at 43°impairs only the maximal rate of AIB uptake, i.e., Vmax.The thermal effect ...

Th e energetically challenging periods of molting and breeding are usually temporally separated in temperate birds, but can occur simultaneously in tropical birds, a condition known as molt – breeding overlap. Here, we document great variation in the timing and duration of molting and breeding, and in the extent of molt – breeding overlap, among 87 species of understory passerines in central Am...

BACKGROUND Many animals display colorful signals in their integument which convey information about the quality of their bearer. Theoretically, these ornaments incur differential production and/or maintenance costs that enforce their honesty. However, the proximate mechanisms of production costs are poorly understood and contentious in cases of non-carotenoid-based plumage ornaments like the me...

BACKGROUND Leukemia is a malignant proliferative disorder of the hematopoietic cells. The important role of angiogenesis in leukemia has been reported by several studies. Matrix metalloproteinases (MMPs) are a large group of endopeptidases which degredate the extracellular matrix and play an important role in angiogenesis. OBJECTIVE The present study was conducted to evaluate the patterns of ...

SYNOPSIS. The ability to change reproductive tactics during adult development in response to environmental variation is predicted to enhance fitness. Many organisms show phenotypic plasticity early in nonembryonic development, but later exhibit phases of developmental inflexibility (5canalization). Therefore, we studied reproduction-related hormones and proteins and their relationships to plast...