Conserved and divergent patterns of expression of DAZL,VASA and OCT4 in the germ cells of the human fetal ovary and testis

Background  

Germ cells arise from a small group of cells that express markers of pluripotency including OCT4. In humans formation of gonadal compartments (cords in testis, nests in ovary) takes place during the 1st trimester (6–8 weeks gestation). In the 2nd trimester germ cells can enter meiotic prophase in females whereas in males this does not occur until puberty. We have used qRTPCR, Westerns and immunohistochemical profiling to determine which of the germ cell subtypes in the human fetal gonads express OCT4, DAZL and VASA, as these have been shown to play an essential role in germ cell maturation in mice.     

Possible significance of variation in the larval development of palaemonid shrimp

Time of metamorphosis and postlarval development were found to be unrelated in the palaemonid shrimp Macrobrachium rosenbergii (de Man). However, in addition to being influenced by environmental factors, the tendency of a particular palaemonid (Palaemonetes spp.) larva to pass through a given number of larval instars may be inheritable. It is suggested that variation in the duration of the planktonic larval phase and the number of larval instars may help to ensure the dispersal of sibling larvae and thus enhances the survival of the parental genotypes. Also, such variation may increase the probability of recruitment to existing parental populations and the likelihood of successful colonization of freshwater environments.     

Can short-term fasting protect against doxorubicin-induced cardiotoxicity?

Doxorubicin(Dox) is one of the most effective chemotherapeutic agents used in the treatment of several types of cancer. However the use is limited by cardiotoxicity. Despite extensive investigation into the mechanisms of toxicity and preventative strategies, Dox-induced cardiotoxicity still remains a major cause of morbidity and mortality in cancer survivors. Thus, continued research into preventative strategies is vital. Short-term fasting has proven to be cardioprotective against a variety of insults. Despite the potential, only a few studies have been conducted investigating its ability to prevent Dox-induced cardiotoxicity. However, all show proof-of-principle that short-term fasting is cardioprotective against Dox. Fasting affects a plethora of cellular processes making it difficult to discern the mechanism(s) translating fasting to cardioprotection, but may involve suppression of insulin and insulin-like growth factor-1 signaling with stimulated autophagy. It is likely that additional mechanisms also contribute. Importantly, the literature suggests that fasting may enhance the antitumor activity of Dox. Thus, fasting is a regimen that warrants further investigation as a potential strategy to prevent Dox-induced cardiotoxicity. Future research should aim to determine the optimal regimen of fasting, confirmation that this regimen does not interfere with the antitumor properties of Dox, as well as the underlying mechanisms exerting the cardioprotective effects.     

Effects of acute doxorubicin treatment on hepatic proteome lysine acetylation status and the apoptotic environment

AIM: To determine if doxorubicin(Dox) alters hepatic proteome acetylation status and if acetylation status was associated with an apoptotic environment. METHODS: Doxorubicin(20 mg/kg; Sigma, Saint Louis, MO; n = 8) or NaCl(0.9%; n = 7) was administered as an intraperitoneal injection to male F344 rats, 6-wk of age. Once animals were treated with Dox or saline, all animals were fasted until sacrifice 24 h later. RESULTS: Dox treatment decreased proteome lysine acetylation likely due to a decrease in histone acetyltransferase activity. Proteome deacetylation may likely not be associated with a proapoptotic environment. Dox did not increase caspase-9,-8, or-3 activation nor poly(adenosine diphosphate-ribose) polymerase-1 cleavage. Dox did stimulate caspase-12 activation, however, it likely did not play a role in apoptosis induction. CONCLUSION: Early effects of Dox involve hepatic proteome lysine deacetylation and caspase-12 activa-tion under these experimental conditions.     

A Perspective on the History and Evolution of an Oceans and Human Health “Metadiscipline” in the USA

We review recent history and evolution of Oceans and Human Health programs and related activities in the USA from a perspective within the Federal government. As a result of about a decade of support by the US Congress and through a few Federal agencies, notably the National Science Foundation, National Institute of Environmental Health Sciences, and National Ocean and Atmospheric Administration, robust Oceans and Human Health (OHH) research and application activities are now relatively widespread, although still small, in a number of agencies and academic institutions. OHH themes and issues have been incorporated into comprehensive federal ocean research plans and are reflected in the new National Ocean Policy enunciated by Executive Order 13547. In just a decade, OHH has matured into a recognized “metadiscipline,” with development of a small, but robust and diverse community of science and practice, incorporation into academic educational programs, regular participation in ocean and coastal science and public health societies, and active engagement with public health decision makers. In addition to substantial increases in scientific information, the OHH community has demonstrated ability to respond rapidly and effectively to emergency situations such as those associated with extreme weather events (e.g., hurricanes, floods) and human-caused disasters (e.g., the Deep Water Horizon oil spill). Among many other things, next steps include development and implementation of agency health strategies and provision of specific services, such as ecological forecasts to provide routine early warnings for ocean health threats and opportunities for prevention and mitigation of these risks.     

Habitat variables associated with encounters of Hottentot Buttonquail Turnix hottentottus during flush surveys across the Fynbos biome

The Hottentot Buttonquail Turnix hottentotus is an endangered terrestrial turnicid and is endemic to the Fynbos biome, South Africa. Due to its secretive nature and apparent rarity almost nothing is known about the species, but its range has been subject to anthropogenic modification, invasion by alien plant species and is vulnerable to climate change. To model covariates associated with the presence of Hottentot Buttonquail we undertook flush surveys across the Fynbos biome, covering 275 km. Habitat variables at encounter sites were recorded in vegetation plots, as well as locations without encounters. There was a critical number of observers needed during a flush survey in order to account for buttonquail presence, with no encounters with less than five participants. After accounting for this, we found probability of encounters decreased with increasing time-since-fire. Probability of encounters were also negatively associated with increasing percentage grass and other vegetation cover. We also found no association between percentage cover of Restionaceae plants and encounter probability, considered previously to be the best indicator of Hottentot Buttonquail presence. This information will be of use to those interested in managing habitat for this species and should inform future conservation efforts.     

Vulnerability of birds to contaminated water sources in the Karoo region of South Africa

The Karoo is a unique region in South Africa in terms of its ecological processes and endemic species. Large areas are needed to maintain viable populations of nomadic birds that follow erratic rainfall events and subsequent food and nesting resources, as well as ephemeral standing water. Whereas many species are adapted to arid conditions, our trait-based analysis found that an unusually large percentage (almost 45%) of 315 bird species in the semi-arid Karoo region rely on water to some degree. Indeed, some birds may have benefited from human activities to date, such as through the provision of water for livestock. However, this reliance on water makes birds vulnerable to changes in water quality stemming from various industrial developments. Given the large areas of the Karoo under consideration for concessions, the most noteworthy of these is hydraulic fracturing for shale gas, which results in a large quantity of waste water (‘produced water’) that contains a wide variety of chemicals, including petroleum byproducts. Given the negative impacts of secondary waste water on wildlife in other parts of the world where shale-gas exploration is being undertaken, careful attention must be given to preventing access to such produced water by an estimated 60 to 141 species of birds that make use of the water in the Karoo.     

Potent effects of aerosol compared with intravenous treprostinil on the pulmonary circulation.

Inhaled vasodilator therapy for pulmonary hypertension may decrease the systemic side effects commonly observed with systemic administration. Inhaled medications only reach ventilated areas of the lung, so local vasodilation may improve ventilation-perfusion matching and oxygenation. We compared the effects of intravenous vs. aerosolized treprostinil on pulmonary and systemic hemodynamics in an unanesthetized sheep model of sustained acute pulmonary hypertension. Acute, stable pulmonary hypertension was induced in instrumented unanesthetized sheep by infusing a PGH(2) analog, U-44069. The sheep were then administered identical doses of treprostinil either intravenously or by aerosol. Systemic and pulmonary hemodynamics were recorded during each administration. Both intravenous and aerosol delivery of treprostinil reduced pulmonary vascular resistance and pulmonary arterial pressure, but the effect was significantly greater with aerosol delivery (P < 0.05). Aerosol delivery of treprostinil had minimal effects on systemic hemodynamics, whereas intravenous delivery increased heart rate and cardiac output and decreased left atrial pressure and systemic blood pressure. Aerosol delivery of the prostacyclin analog treprostinil has a greater vasodilatory effect in the lung with minimal alterations in systemic hemodynamics compared with intravenous delivery of the drug. We speculate that this may result from treprostinil stimulated production of vasodilatory mediators from pulmonary epithelium.