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Comment by Dr. Krishna Kumari Challa on January 16, 2024 at 3:40pm

Caterpillars (Spodoptera litura) were set upon leaves cut from tomato plants and Arabidopsis thaliana, a common weed in the mustard family, and the researchers imaged the responses of a second, intact, insect-free Arabidopsis plant to those danger cues.

These plants weren't any ordinary weeds: they had been genetically altered so their cells contained a biosensor that fluoresced green when an influx of calcium ions was detected. Calcium signaling is something human cells use to communicate too.

The team used a similar technique to measure calcium signals in a study last year of fluorescent Mimosa pudica plants, which quickly move their leaves in response to touch, to avoid predators.

This time, the team visualized how plants responded to being bathed in volatile compounds, which plants release within seconds of wounding.

Part 2

Comment by Dr. Krishna Kumari Challa on January 16, 2024 at 3:39pm

Scientists Film Plant 'Talking' to Its Neighbour

Imperceptible to us, plants are surrounded by a fine mist of airborne compounds that they use to communicate and protect themselves. Kind of like smells, these compounds repel hungry herbivores and warn neighboring plants of incoming assailants.

Scientists have known about these plant defenses since the 1980s, detecting them in over 80 plant species since then. Now, a team of Japanese researchers has deployed real-time imaging techniques to reveal how plants receive and respond to these aerial alarms.

This was a big gap in our understanding of plant chatter: we knew how plants send messages, but not how they receive them.

In this study, Yuri Aratani and Takuya Uemura, molecular biologists at Saitama University in Japan, and colleagues rigged up a pump to transfer compounds emitted by injured and insect-riddled plants onto their undamaged neighbors, and a fluorescence microscope to watch what happened.

Comment by Dr. Krishna Kumari Challa on January 16, 2024 at 2:44pm

Joining the ranks of existing polydrugs
Kush is another example of polydrug mixtures of which forensic scientists are becoming increasingly aware. Another tobacco and cannabis-based drug, nyaope, otherwise known as whoonga, is found in South Africa.

This time the tobacco and cannabis are mixed with heroin and antiretroviral drugs used to treat Aids, some of which are hallucinogenic.

A further polydrug, "white pipe", a mixture of methaqualone (Mandrax), cannabis and tobacco, is smoked in southern Africa.

These drugs are inexpensive and provide an escape from unemployment, the drudgery of poverty, sexual and physical abuse, and the effect, in some cases, especially in west Africa, from having been a child soldier.
So what can be done about these drugs? The effectiveness of legislation alone is questionable, and many of those who attend the very limited rehabilitation centres return to drug use.

Perhaps what is required is an integrated forensic healthcare system where legislative control is backed up by properly resourced rehabilitation centres coupled with a public health and employment programme. What changes are made in response to this epidemic remains to be seen.

Michael Cole, Professor of Forensic Science, Anglia Ruskin University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Part 3

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Comment by Dr. Krishna Kumari Challa on January 16, 2024 at 2:43pm

Where is the drug found?
The drug is reported in both Guinea and Liberia, which share porous land borders with Sierra Leone, making drug trafficking easy.

Kush costs around five leones (20 UK pence) per joint, which may be used by two or three people, with up to 40 joints being consumed in a day.

This represents a massive spend on drugs and illustrates the addictive nature of the mixture, in a country where the annual income per capita is around £500.

The effects of the drug vary and depend on the user and the drug content. Cannabis causes a wide variety of effects, which include euphoria, relaxation and an altered state of consciousness.
Fentanyl, an extremely potent opioid, produces euphoria and confusion and causes sleepiness among a wide range of other side-effects.

Similarly, tramadol, which is also an opioid but less potent than fentanyl (100mg tramadol has the same effect as 10mg morphine) results in users becoming sleepy and "spaced out" – disconnected from things happening around them.

The danger of the drug is twofold: the risk of self-injury to the drug taker and the highly addictive nature of the drug itself. A further problem is the need to finance the next dose, often achieved through prostitution or criminal activity
Part 2

Comment by Dr. Krishna Kumari Challa on January 16, 2024 at 2:42pm

Deadly 'Zombie Drug' Believed to Contain Human Bones Wreaks Havoc in West Africa

A new drug called kush is wreaking havoc in west Africa, particularly in Sierra Leone where it is estimated to kill around a dozen people each week and hospitalise thousands.
The drug, taken mostly by men aged 18 to 25, causes people to fall asleep while walking, to fall over, to bang their heads against hard surfaces and to walk into moving traffic.
Kush should not be confused with the drug of the same name found in the US, which is a mixture of "an ever-changing host of chemicals" sprayed on plant matter and smoked.

Kush in Sierra Leone is quite different; it is a mixture of cannabis, fentanyl, tramadol, formaldehyde and – according to some – ground down human bones.

It is mixed by local criminal gangs, but the constituent drugs have international sources, facilitated no doubt by the internet and digital communications.

While cannabis is widely grown in Sierra Leone, the fentanyl is thought to originate in clandestine laboratories in China where the drug is manufactured illegally and shipped to west Africa.

Tramadol has a similar source, namely illegal laboratories across Asia. Formaldehyde, which can cause hallucinations, is also reported in this mixture.

As for ground human bones, there is no definitive answer about whether or not they occur in the drug, where such bones would come from, or why they might be incorporated into the drug.

Some people say that grave robbers provide the bones, but there is no direct evidence of this.
But why would bones be incorporated into the drug? Some suggest that the sulphur content of the bones causes a high. Another reason might be the drug content of the bones themselves, if the deceased was a fentanyl or tramadol user.

However, both are unlikely. Sulphur levels in bones are not high. Smoking sulphur would result in highly toxic sulphur dioxide being produced and inhaled. Any drug content in bones is orders of magnitude less than that required to cause a physiological effect.
Part 1

Comment by Dr. Krishna Kumari Challa on January 16, 2024 at 7:00am

The researchers set out to study how water molecules are affected by the distribution of ions at the exact point where air and water meet. Traditionally, this has been done with a technique called vibrational sum-frequency generation (VSFG). With this laser radiation technique, it is possible to measure molecular vibrations directly at these key interfaces.

However, although the strength of the signals can be measured, the technique does not measure whether the signals are positive or negative, which has made it difficult to interpret findings in the past. Additionally, using experimental data alone can give ambiguous results.

The team overcame these challenges by utilizing a more sophisticated form of VSFG, called heterodyne-detected (HD)-VSFG, to study different electrolyte solutions. They then developed advanced computer models to simulate the interfaces in different scenarios.

The combined results showed that both positively charged ions, called cations, and negatively charged ions, called anions, are depleted from the water/air interface. The cations and anions of simple electrolytes orient water molecules in both up- and down-orientation. This is a reversal of textbook models, which teach that ions form an electrical double layer and orient water molecules in only one direction.
This work demonstrates that the surface of simple electrolyte solutions has a different ion distribution than previously thought and that the ion-enriched subsurface determines how the interface is organized: at the very top there are a few layers of pure water, then an ion-rich layer, then finally the bulk salt solution.

Kuo-Yang Chiang et al, Surface stratification determines the interfacial water structure of simple electrolyte solutions, Nature Chemistry (2024). DOI: 10.1038/s41557-023-01416-6. www.nature.com/articles/s41557-023-01416-6

Comment by Dr. Krishna Kumari Challa on January 16, 2024 at 6:59am

Water molecule discovery contradicts textbook models

Textbook models will need to be re-drawn after a team of researchers found that water molecules at the surface of salt water are organized differently than previously thought.

Many important reactions related to climate and environmental processes take place where water molecules interface with air. For example, the evaporation of ocean water plays an important role in atmospheric chemistry and climate science. Understanding these reactions is crucial to efforts to mitigate the human effect on our planet.

The distribution of ions at the interface of air and water can affect atmospheric processes. However, a precise understanding of the microscopic reactions at these important interfaces has so far been intensely debated.

In a paper published in the journal Nature Chemistry, researchers show that ions and water molecules at the surface of most salt-water solutions, known as electrolyte solutions, are organized in a completely different way than traditionally understood. This could lead to better atmospheric chemistry models and other applications.

Part 1

Comment by Dr. Krishna Kumari Challa on January 15, 2024 at 8:36am

The researchers first homed in on Nod1 by analyzing public databases of human embryos, then studied the receptor further using zebrafish, a commonly used model organism that shares roughly 70 percent of its genome with humans. By inhibiting or boosting Nod1, the researchers demonstrated a positive correlation with the creation of blood stem cells.

Most of a person's blood stem cells reside in their bone marrow, so patients with certain blood disorders often need a bone marrow transplant to provide a vital supply of blood stem cells.

But armed with this evidence about Nod1's role in creating blood stem cells in embryos, scientists have new hope for devising a way to produce new blood stem cells from human samples, potentially even from patients' own blood.

That could help avoid not only the logistical challenges of arranging and performing bone marrow transplants, the researchers note, but also complications like graft-versus-host disease, in which transplanted immune cells recognize the host as foreign and attack the recipient's cells.

https://www.nature.com/articles/s41467-023-43349-1.pdf

Part 2

Comment by Dr. Krishna Kumari Challa on January 15, 2024 at 8:34am

The Key to Creating Blood Stem Cells May Lie in Your Own Blood

The development of blood stem cells relies on a seemingly unrelated microbe-sensing protein receptor, according to a new study.

The discovery could break new ground in the ongoing quest to produce blood stem cells from a person's own blood – thereby negating the need for bone marrow transplants.

The protein receptor in question, called Nod1, is already known for its role in helping recognize bacterial infections in the body and rallying an immune response, the study's authors note.

But according to their research, Nod1 also seems to serve a different purpose much earlier in life, when an embryo's vascular system is still developing.

The study suggests this microbial sensor helps embryos force some of their vascular endothelial cells to become blood stem cells.

That could be valuable information, given its potential for shedding light on how an embryo makes blood stem cells – and perhaps how we can grow them much later in life, too.

This would eliminate the challenging task of finding compatible bone marrow transplant donors and the complications that occur after receiving a transplant, improving the lives of many leukemia, lymphoma, and anemia patients.

Blood stem cells are progenitors of all white and red cells in our blood, producing all the components of our blood in a process called hematopoiesis.

These blood stem cells, also known as hematopoietic stem cells, arise themselves in the body before birth, developing from endothelial cells within an embryo's aorta.

Part 1

Comment by Dr. Krishna Kumari Challa on January 14, 2024 at 10:42am

First prehistoric people with different syndromes identified from ancient DNA

Researchers  have developed a new technique to measure the number of chromosomes in ancient genomes more precisely, using it to identify the first prehistoric person with mosaic Turner syndrome (characterized by one X chromosome instead of two [XX]), who lived about 2,500 years ago.

As part of their research published in Communications Biology, they also identified the earliest known person with Jacob's syndrome (characterized by an extra Y chromosome—XYY) in the Early Medieval Period, three people with Klinefelter syndrome (characterized by an extra X chromosome—XXY) across a range of time periods, and an infant with Down Syndrome from the Iron Age.

Most cells in the human body have 23 pairs of DNA molecules called chromosomes, and the sex chromosomes are typically XX (female) or XY (male), although there are differences in sexual development. Aneuploidy occurs when a person's cells have an extra or missing chromosome. If this occurs in the sex chromosomes, a few differences like delayed development or changes in height can be seen around puberty.

Ancient DNA samples can erode over time and can be contaminated by DNA from other ancient samples or from people handling them. This makes it difficult to accurately capture differences in the number of sex chromosomes.

The team  of researchers developed a computational method that aims to pick up more variation in sex chromosomes. For the sex chromosomes, it involves counting the number of copies of X and Y chromosomes, and comparing the outcome to a predicted baseline (what you would expect to see).

The team used the new method to analyze ancient DNA from a large dataset of individuals collected as part of their Thousand Ancient British Genomes project across British history, identifying six individuals with aneuploidies across five sites in Somerset, Yorkshire, Oxford and Lincoln (two sites). The individuals lived across a range of time periods, from the Iron Age (2,500 years ago) up to the Post-Medieval Period (about 250 years ago).

They identified five people who had sex chromosomes that fell outside the XX or XY categories. All were buried according to their society's customs, although no possessions were found with them to shed more light on their lives.

The three individuals with Klinefelter syndrome lived across very different time periods, but they shared some similarities—all were slightly taller than average and showed signs of delayed development in puberty.

By investigating details on the bones, the research team could see that it was unlikely that the individual with Turner syndrome had gone through puberty and started menstruation, despite their estimated age of 18-22. Their syndrome was shown to be mosaic; some cells had one copy of chromosome X and some had two.

Through precisely measuring sex chromosomes, they were able to show the first prehistoric evidence of Turner syndrome 2,500 years ago, and the earliest known incidence of Jacob's syndrome around 1,200 years ago. It's hard to see a full picture of how these individuals lived and interacted with their society, as they weren't found with possessions or in unusual graves, but it can allow some insight into how perceptions of gender identity have evolved over time.

 Detection of chromosomal aneuploidy in ancient genomes. Communications Biology, 2024; 7 (1) DOI: 10.1038/s42003-023-05642-z

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