Topic 38: Research (Phần 2)

Commentary from researchers in the College of Pharmacy at The University of Texas at Austin in the journal Science provide new findings in alcohol use disorder (AUD) research. The article, “Compelled to drink: Why some cannot stop,” considers recent findings by researchers Siciliano et al. that discovered individual differences in the activity of neurons in a frontal cortex to brain stem circuit that predicts the later escalation of alcohol drinking to compulsive intake in a mouse model. “These researchers not only defined a new brain circuit involved in compulsive drinking, but showed individual differences at the level of electrical activity in the neurons that comprise this circuit,” Nixon said. “The individual differences in electrical activity predicted which mice would go on to drink compulsively after a binge-like drinking episode despite drinking the same amount of alcohol during that episode.”

The research group previously found that this circuit is important for responses to aversive events, and they have now asked why aversive outcomes don’t deter everyone from drinking alcohol. These new findings point to a neurological explanation for why only some mice continue to drink alcohol even when it comes with negative consequences. “They found these differences in circuit activity before mice developed compulsive drinking behavior,” Mangieri said. “In other words, some mice had a biological predisposition that made them susceptible to developing alcohol drinking behaviors that are similar to humans with AUD.”

The researchers said the work has important implications. It has potential as a biomarker of propensity to develop severe AUD based on electrical activity. Also, the discovery of this circuit’s role in compulsive drinking suggests that there may be novel pharmacological targets that could be identified and developed for the treatment of AUDs.

(Source: https://news.utexas.edu/)

As cases of coronavirus infection proliferate around the world and governments take extraordinary measures to limit the spread, there is still a lot of confusion about what exactly the virus does to people’s bodies. The symptoms — fever, cough, shortness of breath — can signal any number of illnesses, from flu to strep to the common cold.

The virus is spread through droplets transmitted into the air from coughing or sneezing, which people nearby can take in through their nose, mouth or eyes. The viral particles in these droplets travel quickly to the back of your nasal passages and to the mucous membranes in the back of your throat, attaching to a particular receptor in cells, beginning there. Coronavirus particles have spiked proteins sticking out from their surfaces, and these spikes hook onto cell membranes, allowing the virus’s genetic material to enter the human cell. That genetic material proceeds to “hijack the metabolism of the cell and say, in effect, ‘Don’t do your usual job. Your job now is to help me multiply and make the virus,’” said Dr. William Schaffner.

As copies of the virus multiply, they burst out and infect neighboring cells. The virus then “crawls progressively down the bronchial tubes,” Dr. Schaffner said. When the virus reaches the lungs, their mucous membranes become inflamed. That can damage the alveoli or lung sacs and they have to work harder to carry out their function of supplying oxygen to the blood that circulates throughout our body and removing carbon dioxide from the blood so that it can be exhaled. The swelling and the impaired flow of oxygen can cause those areas in the lungs to fill with fluid, pus and dead cells. Pneumonia, an infection in the lung, can occur.

(Source: https://www.nytimes.com/)

In all the debate about conservation of natural landscapes, we must not forget that the 19th century also saw the development of interest in the cultural past. Although archaeology was around 100 years old at this point, at least in the Old World, it was largely an exercise in treasure hunting - digging up the treasures of the past as curiosities for museums or for the private collections of those who funded the dig.

Changes in attitudes and law throughout the 19th century meant that monuments and artefacts were becoming part of the study of the past, no longer merely trinkets and curiosities, but indicators of a culture’s development and identity. Modern archaeology would not arrive until the 20th century and the concept of an archaeological landscape is younger still. The first laws to protect and conserve cultural heritage came into place in the late 19th and early 20th centuries in the developed countries. In the US, the first such law was the Antiquities Act in 1906 which gave the office of president the power to set aside areas of land as protected cultural assets, known as “National Monuments”. This law was in place until 1979 when it was replaced with the Archaeological Resources Protection Act but several other laws came into place before then that required archaeologists to label and give proper contexts to monuments and artefacts.

There was also a global movement to protect by law and provide resources and funds for monuments that were nationally important, but also those deemed significant to human civilization as a whole. Founded in 1945, has many responsibilities, one of the most important as far as archaeological conservation is concerned is the World Heritage List. The list began in 1975 as a recognition of globally important sites. The first 12 added on that first day included: L’Anse Aux Meadows in Canada, The Galapagos Islands, Quito in Ecuador, Krakow, and Mesa Verde National Park in the US. Today, there are over 1,000 cultural monuments and natural landscapes on this list.

In the 21st century, it is common for countries to have laws in place to protect monuments, sites, and landscapes of cultural or historical importance and government-established charities or government departments assigned to their management, upkeep or conservation. The threats to them and their conservation go beyond the issues of the 19th century (plunder and theft).

(Source: https://www.environmentalscience.org/)

Without regular supplies of some hormones our capacity to behave would be seriously impaired; without others we would soon die. Tiny amounts of some hormones can modify our moods and our action, our inclination to eat or drink, our aggressiveness or submissiveness, and our reproductive and parental behavior. And hormones do more than influence adult behavior; early in life they help to determine the development of bodily form and may even determine an individual’s behavioral capacities. Later in life the changing outputs of some endocrine glands and the body’s changing sensitivity to some hormones are essential aspects of the phenomena of aging.

Communication within the body and the consequent integration of behavior were considered the exclusive province of the nervous system up to the beginning of the present century. The emergence of endocrinology as a separate discipline can probably be traced to the experiments of Bayliss and Starling on the hormone secretion. This substance is secreted from cells in the intestinal walls when food enters the stomach; it travels through the bloodstream and stimulates the pancreas to liberate pancreatic juice, which aids in digestion. By showing that special cells secrete chemical agents that are conveyed by the bloodstream and regulate distant target organs or tissues, Bayliss and Starling demonstrated that chemical integration can occur without participation of the nervous system.

William Bayliss and Ernest Henry Starling, two British physiologists, discovered and introduced the word hormone. In 1979, The Bayliss and Starling Society was founded as a forum for research scientists with specific interest in the chemistry, physiology and function of central and autonomic peptides. The Society also offered the travelling fellowship award for members who wanted to attend national and international academic conferences. Sometimes, the Society help schools to organize science fairs for secondary students and give them incentives to fall for related subjects.

The term “hormone” was first used with reference to secretion. Starling derived the term from the Greek hormone, meaning “to excited or set in motion.” The term “endocrine” was introduced shortly thereafter, “Endocrine” is used to refer to glands that secrete products into the bloodstream. The term “endocrine” contrasts with “exocrine” which is applied to glands that secrete their products through ducts to the site of action. Examples of exocrine glands are the tear glands, the sweat glands, and the pancreas, which secretes pancreatic juice through a duct into intestine. Exocrine glands are also called duct glands, while endocrine glands are called ductless.

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