No abstract

Primary pigmented nodular adrenocortical disease (PPNAD) is a rare cause of Cushing syndrome in infants, children, and young adults. It is characterized by non-adrenocorticotropic hormone-dependent hypersecretion of cortisol by multiple, pigmented nodules of hyperplastic adrenocortical cells. With a single exception, adrenal glands have been described as normal with computed tomography (CT) in all previous series. Eight patients had Cushing syndrome due to surgically proved PPNAD. Four of the eight patients had stigmas of Carney complex (lentigines, calcified Sertoli cell tumors of the testes, and cardiac and soft-tissue myxomas). CT and/or magnetic resonance (MR) imaging demonstrated unilateral or bilateral nodularity in five of six patients examined. Macronodules (greater than 10 mm) were seen in the two oldest patients. As the clinical presentation of Cushing syndrome in this group of patients may be atypical (severe osteoporosis or short stature), the detection of multiple, small adrenocortical nodules with CT or MR imaging supports, or may even suggest, the diagnosis of PPNAD.

We evaluated the passage of early‐stage fishes through the Salto Grande Dam using high‐frequency downstream ichthyoplankton monitoring and five surveys involving samples taken upstream and downstream of the dam. Eggs and larvae of migratory fishes were captured downstream of the dam, usually during high discharges. Upstream and downstream larvae were frequently unyolked, which corresponds to individuals aged 4+ days, and represents a time significantly longer than that required for the displacement of the water mass from the dam to the sampling location. In low flow rate surveys, fish larvae of the same species and degree of development were captured immediately upstream and at 1, 10, 24 and 40 km downstream of the dam. The densities and percentage of Pimelodinae larvae captured alive by short time and low speed tows were similar upstream and downstream of the dam, indicating that larval mortality was a result of sampling and not to the passage through the turbines. The results show that the larvae of fish that spawn in the middle section are partly transported to the lower section, and suggest that both spillway and turbine discharge should be considered part of the passage. We also found evidence that the passage of small and fragile Pimelodinae larvae through the Salto Grande Kaplan turbines does not significantly affect survival rates. Copyright © 2016 John Wiley & Sons, Ltd.

No abstract

Previous studies showed that cytosolic and microsomal fractions from rat ventral prostate are able to biotransform ethanol to acetaldehyde and 1-hydroxyethyl radicals via xanthine oxidase and a non P450 dependent pathway respectively. Sprague Dawley male rats were fed with a Lieber and De Carli diet containing ethanol for 28 days and compared against adequately pair-fed controls. Prostate microsomal fractions were found to exhibit CYP2E1-mediated hydroxylase activity significantly lower than in the liver and it was induced by repetitive ethanol drinking. Ethanol drinking led to an increased susceptibility of prostatic lipids to oxidation, as detected by t-butylhydroperoxide-promoted chemiluminiscence emission and increased levels of lipid hydroperoxides (xylenol orange method). Ultrastructural alterations in the epithelial cells were observed. They consisted of marked condensation of chromatin around the perinuclear membrane, moderate dilatation of the endoplasmic reticulum and an increased number of epithelial cells undergoing apoptosis. The prostatic alcohol dehydrogenase activity of the stock rats was 4.84 times lower than that in the liver and aldehyde dehydrogenase activity in their microsomal, cytosolic and mitochondrial fractions was either not detectable or significantly less intense than in the liver. A single dose of ethanol led to significant acetaldehyde accumulation in the prostate. The results suggest that acetaldehyde accumulation in prostate tissue might result from both acetaldehyde produced in situ but also because of its low aldehyde dehydrogenase activity and its poor ability to metabolize acetaldehyde arriving via the blood. Acetaldehyde, 1-hydroxyethyl radical and the oxidative stress produced may lead to epithelial cell injury.

Prochilodus lineatus (Val.) is one of the main target species of South American freshwater fisheries. The following null hypotheses regarding juvenile recruitment of P. lineatus were tested: (a) recruitment is not determined by variations in larval abundance and (b) recruitment is not determined by variations in discharge. For this purpose, variations in abundance of larvae in main channel drift and monthly captures of juveniles in a floodplain lake of the River Paraná were examined weekly between 2009 and 2016. Mean annual abundances of larval densities and CPUE of juveniles were correlated with a set of hydrometric variables. A positive correlation was found between the abundance of juveniles with high and persistent flood pulses. By contrast, larval abundance was not correlated with juvenile abundance. Pronounced contrast was found in the recruitment of P. lineatus between years of high and low discharge, which supports the hypothesis that floods are the main determining factor for recruitment of this species.

There is available evidence supporting a positive association between alcohol intake and risk of breast cancer. However, there is limited information regarding possible mechanisms for this effect. Past studies from our laboratory suggest that acetaldehyde accumulation in mammary tissue after alcohol intake may be of particular relevance and that cytosolic and microsomal in situ bioactivation of ethanol to acetaldehyde and free radicals and the resulting stimulation of oxidative stress could be a significant early event related to tumor promotion. In the present studies repetitive alcohol drinking for 28 days was found to produce significant decreases in the mammary tissue content of GSH and alpha tocopherol and in glutathione S-transferase or glutathione reductase activities. In contrast, glutathione peroxidase activity was slightly increased. Malondialdehyde determinations did not show the occurrence of lipid peroxidation while the xylenol orange procedure gave positive results. The mammary microsomal metabolism of ethanol to acetaldehyde was not induced after an acute dose of ethanol or acetone able to induce the activity of its liver counterpart. The cytosolic pathway of alcohol metabolism instead was significantly enhanced by these two treatments. No increased generation of comet images was found either in mammary tissue or in liver under the experimental conditions tested. Results suggest that, while acetaldehyde accumulation in mammary tissue could be a critical event resulting from increasing production of acetaldehyde in situ plus an additional amount of it arriving via blood, other factors such as poor handling of the accumulated acetaldehyde could be also relevant.

CCl4 has been reported to be a liver carcinogen for several mice strains, for Syrian Golden hamsters, but not for Sprague-Dawley rats. CCl4 is an experimental carcinogen for which no convincing evidence of mutagenicity is available despite the fact that CCl4 reactive metabolites bind covalently to liver DNA. Here we describe studies on the relationship between the intensities of the covalent binding (CB) of CCl4 reactive metabolites to liver DNA and nuclear proteins either in vivo or in vitro after activation to reactive metabolites by nuclear preparations, considering the known susceptibility of the C3H mice, Syrian Golden hamsters and Sprague-Dawley rats to CCl4. There was no correlation between the intensity of CCl4 carcinogenic effects on the liver and CB of CCl4 reactive metabolites to total DNA either in vitro or in vivo. A good correlation between carcinogenicity and CB to total nuclear proteins (in vivo or in vitro was found. Nuclear protein fractionation studies revealed CB of CCl4 reactive metabolites to both histone and non-histone proteins when nuclear preparations activated CCl4 either in the presence or absence of NADPH. Acidic and residual nuclear proteins were the favorite targets of the interaction with CCl4 reactive metabolites. A good correlation between CB to these nuclear protein fractions and CCl4 carcinogenicity in the three species was found.