Effect of sucrose on lipogenesis of rats chronically treated with ethanol

The effect of chronic ethanol administration with and without sucrose on the lipogenic enzymes of liver and adipose tissue of rats was studied. Ethanol markedly influenced the adipose lipogenic enzymes at 28 days. Sucrose caused a 2-10fold increase in lipogenic enzymes of both adipose and liver.     

A regular period for Saturn's magnetic field that may track its internal rotation

The rotation rate of a planet is one of its fundamental properties. Saturn's rotation, however, is difficult to determine because there is no solid surface from which to time it, and the alternative 'clock'--the magnetic field--is nearly symmetrically aligned with the rotation axis. Radio emissions, thought to provide a proxy measure of the rotation of the magnetic field, have yielded estimates of the rotation period between 10 h 39 min 22 s and 10 h 45 min 45 s (refs 8-10). Because the period determined from radio measurements exhibits large time variations, even on timescales of months, it has been uncertain whether the radio-emission periodicity coincides with the inner rotation rate of the planet. Here we report magnetic field measurements that revealed a time-stationary magnetic signal with a period of 10 h 47 min 6 s +/- 40 s. The signal appears to be stable in period, amplitude and phase over 14 months of observations, pointing to a close connection with the conductive region inside the planet, although its interpretation as the 'true' inner rotation period is still uncertain.     

Transiting extrasolar planetary candidates in the Galactic bulge

More than 200 extrasolar planets have been discovered around relatively nearby stars, primarily through the Doppler line shifts owing to reflex motions of their host stars, and more recently through transits of some planets across the faces of the host stars. The detection of planets with the shortest known periods, 1.2-2.5 days, has mainly resulted from transit surveys which have generally targeted stars more massive than 0.75 M(o), where M(o) is the mass of the Sun. Here we report the results from a planetary transit search performed in a rich stellar field towards the Galactic bulge. We discovered 16 candidates with orbital periods between 0.4 and 4.2 days, five of which orbit stars of masses in the range 0.44-0.75 M(o). In two cases, radial-velocity measurements support the planetary nature of the companions. Five candidates have orbital periods below 1.0 day, constituting a new class of ultra-short-period planets, which occur only around stars of less than 0.88 M(o). This indicates that those orbiting very close to more-luminous stars might be evaporatively destroyed or that jovian planets around stars of lower mass might migrate to smaller radii.     

Targeting C-reactive protein for the treatment of cardiovascular disease

Complement-mediated inflammation exacerbates the tissue injury of ischaemic necrosis in heart attacks and strokes, the most common causes of death in developed countries. Large infarct size increases immediate morbidity and mortality and, in survivors of the acute event, larger non-functional scars adversely affect long-term prognosis. There is thus an important unmet medical need for new cardioprotective and neuroprotective treatments. We have previously shown that human C-reactive protein (CRP), the classical acute-phase protein that binds to ligands exposed in damaged tissue and then activates complement, increases myocardial and cerebral infarct size in rats subjected to coronary or cerebral artery ligation, respectively. Rat CRP does not activate rat complement, whereas human CRP activates both rat and human complement. Administration of human CRP to rats is thus an excellent model for the actions of endogenous human CRP. Here we report the design, synthesis and efficacy of 1,6-bis(phosphocholine)-hexane as a specific small-molecule inhibitor of CRP. Five molecules of this palindromic compound are bound by two pentameric CRP molecules, crosslinking and occluding the ligand-binding B-face of CRP and blocking its functions. Administration of 1,6-bis(phosphocholine)-hexane to rats undergoing acute myocardial infarction abrogated the increase in infarct size and cardiac dysfunction produced by injection of human CRP. Therapeutic inhibition of CRP is thus a promising new approach to cardioprotection in acute myocardial infarction, and may also provide neuroprotection in stroke. Potential wider applications include other inflammatory, infective and tissue-damaging conditions characterized by increased CRP production, in which binding of CRP to exposed ligands in damaged cells may lead to complement-mediated exacerbation of tissue injury.     

High-quality male field crickets invest heavily in sexual display but die young

Only high-quality males can bear the costs of an extreme sexual display. As a consequence, such males are not only more attractive, but they often live longer than average. Recent theory predicts, however, that high-quality males should sometimes invest so heavily in sexual displays that they die sooner than lower quality males. We manipulated the phenotypic quality of field crickets, Teleogryllus commodus, by altering the protein content of their diet. Here we show that nymphs and adult females reared on a high-protein diet lived longer than those on a low-protein diet. In contrast, adult males reared on a high-protein diet died sooner than those on low-protein diets because they invested more energy in calling during early adulthood. Our findings uphold the theoretical prediction that the relationship between longevity and sexual advertisement may be dynamic (that is, either positive or negative), depending on local conditions such as resource availability. Moreover, they caution the use of longevity as a proxy for fitness in sexual selection studies, and suggest avenues for future research on the relationship between sexual attractiveness and ageing.     

Neurofilament proteins in neurodegenerative diseases

The function of neurofilaments, the major component in large myelinated neurons, is not well understood even though they were discovered as structures over 100 years ago. Recent studies have suggested that neuro-filaments are closely related to many neurodegenerative diseases, such as amyotrophic lateral sclerosis, Parkinson disease Alzheimer disease, and diabetes. Using in vitro assays, cultures and transgenic mice, these studies provided new insights into neurofilament function. The function of each subunit, the relationship of neurofilaments with other cytoskeletal elements and their clinical significance are topics of increasing attention.Received 22 June 2004; received after revision 4 August 2004; accepted 19 August 2004     

What’s new in the renin-angiotensin system?

No abstract.  .