toxicity – Page 2 – Shamskm: A site to exchange knowledge and solutions

Redder Ladybirds More Deadly, Say Scientists

By Guest PostFebruary 7, 2012Naturearms race, colour, defensive chemical, ecologist, jon blount, ladybird, liverpool, mike speed, pigmentation, poisonous, precoccinelline, predator, redder wings, signals of animals, spot ladybird, toxic, toxicity, universitiy of exeter, warning signal

A ladybird’s colour indicates how well-fed and how toxic it is, according to an international team of scientists.

Research led by the Universities of Exeter and Liverpool directly shows that differences between animals’ warning signals reveal how poisonous individuals are to predators.

Published in the journal Functional Ecology, the research shows that redder ladybirds are more poisonous than their paler peers. The study reveals that this variation is directly linked to diet in early life, with better-fed ladybirds being more visible and more deadly.

Ecologists have long assumed that there are no individual differences between the warning signals of animals of the same species. More recently, scientists have identified variation between individuals’ warning signals, but have not known if these differences were meaningful and linked to levels of toxicity. (more…)

Yale Researchers Discover Promising Anti-HIV Agents

By Guest PostNovember 23, 2011Health, Sciencebristol myers squibb, chemical compounds, d4t, DNA, effective hiv treatments, festinavir, function of an enzyme, genetic material, hiv 1 reverse transcriptase, hiv and human t cells, hiv drugs, hiv replication, human t cells, infection of human cells, jlj494, karen s anderson, less toxic aids drugs, mariela bollini, non nucleoside reverse transcriptase inhibitors, prevent hiv, prophylactic anti hiv treatment, reverse transcriptase inhibitor, tai shun lin, toxicity, vinay v thakur, wild type, wild type hiv, william h prusoff, william l jorgensen, yung chi tommy cheng, zerit

Researchers at Yale University have discovered new chemical compounds that prevent HIV from replicating in human T-cells. These compounds could result in new, highly effective HIV treatments that are 10 to 2000 times more potent than HIV drugs now on the market.

“The current compounds or slight variants could become drugs,” said Professor William L. Jorgensen, one of two principal investigators behind the research. The other is Karen S. Anderson, a pharmacology professor at Yale School of Medicine. They reported their results online Nov. 15 in the Journal of Medicinal Chemistry. (more…)

Researchers Report Potential for a Moderate New England ‘Red Tide’ in 2011

By Guest PostApril 10, 2011Environmentalexandrium fundyense, alexandrium germination, cyst, darcie couture, dennis mcgillicuddy, don anderson, ecomon, ecosystem monitoring program, gomtox, gulf of maine, gulf of maine toxicity, jane lubchenco, new england shellfish industry, new hampshire coasts, noaa, paralytic shellfish poisoning, psp, psp toxicity, red tides, ruoying he, shellfish beds, stacy knapp, toxic alga, toxicity

*Bloom could be suppressed by changes in ocean conditions in the Gulf of Maine*

Scientists from the NOAA-funded Gulf of Maine Toxicity (GOMTOX) project issued an outlook for a moderate regional bloom of a toxic alga that can cause ‘red tides’ in the spring and summer of this year, potentially threatening the New England shellfish industry. However, there are signs this year’s bloom could be suppressed by recent changes in ocean conditions in the Gulf of Maine.

An abundant seed population in bottom sediments has set the stage for a moderate bloom of the toxic alga Alexandrium fundyense. This organism swims in the water, and divides again and again to form a “bloom” or red tide, but it also produces dormant cells or cysts that fall to the ocean bottom at the end of these blooms where they remain until they germinate the next year to restart the process. (more…)

Pollution Triggers Genetic Resistance Mechanism in a Coastal Fish

By Guest PostFebruary 24, 20112 commentsEnvironmentacushnet river estuary, ahr2, amino acids, antibiotics, atlantic tomcod, bacteria, diana franks, Environment, evolutionary change, fish, fish populations, general electric facilities, genetic receptor, genetic resistance, hudson environment, hudson river, insecticides, insects, isaac wirgin, mark hahn, natural selection, new york, pahs, PCBs, polychlorinated biphenyls, polycyclic aromatic hydrocarbons, protein, receptor gene, stress factors, superfund basic research, tomcod, toxicity, vertebrate population

For 30 years, two General Electric facilities released about 1.3 million pounds of polychlorinated biphenyls (PCBs) into New York’s Hudson River, devastating and contaminating fish populations. Some 50 years later, one type of fish—the Atlantic tomcod—has not only survived but appears to be thriving in the hostile Hudson environment.

Researchers from Woods Hole Oceanographic Institution (WHOI) have joined colleagues from New York University (NYU) and NOAA to investigate this phenomenon and report that the tomcod living in the Hudson River have undergone a rapid evolutionary change in developing a genetic resistance to PCBs. (more…)

First Study of Dispersants in Gulf Spill Suggests a Prolonged Deepwater Fate

By Guest PostJanuary 29, 2011Environmentbiodegradation, biological exposure, chemical dispersant, chromatographic technique, david valentine, deep ocean, deepwater horizon oil spill, dioctyl sodium sulfosuccinate, doss, effects on corals, elizabeth b kujawinski, environmental data, fate of dispersants, gas flow, gulf of mexico, gulf spill, hydrocarbon, levels of methane, marshes and coastlines, melissa c kido soule, oil droplets, oil gas plume, toxicity, wellhead

To combat last year’s Deepwater Horizon oil spill, nearly 800,000 gallons of chemical dispersant were injected directly into the oil and gas flow coming out of the wellhead nearly one mile deep in the Gulf of Mexico. Now, as scientists begin to assess how well the strategy worked at breaking up oil droplets, Woods Hole Oceanographic Institution (WHOI) chemist Elizabeth B. Kujawinski and her colleagues report that a major component of the dispersant itself was contained within an oil-gas-laden plume in the deep ocean and had still not degraded some three months after it was applied.

While the results suggest the dispersant did mingle with the oil and gas flowing from the mile-deep wellhead, they also raise questions about what impact the deep-water residue of oil and dispersant—which some say has its own toxic effects—might have had on environment and marine life in the Gulf. (more…)

Tag Archives: toxicity

Redder Ladybirds More Deadly, Say Scientists

Yale Researchers Discover Promising Anti-HIV Agents

Researchers Report Potential for a Moderate New England ‘Red Tide’ in 2011

Pollution Triggers Genetic Resistance Mechanism in a Coastal Fish

First Study of Dispersants in Gulf Spill Suggests a Prolonged Deepwater Fate