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Comment by Dr. Krishna Kumari Challa on December 5, 2024 at 11:29am

Interestingly, the cancer cells themselves were unable to use fructose readily as a nutrient because they do not express the right biochemical machinery. Liver cells do. This allows them to convert fructose into LPCs, which they can secrete to feed tumors.

Gary Patti, Dietary fructose enhances tumour growth indirectly via interorgan lipid transfer, Nature (2024). DOI: 10.1038/s41586-024-08258-3. www.nature.com/articles/s41586-024-08258-3

Part 2

Comment by Dr. Krishna Kumari Challa on December 5, 2024 at 11:27am

Research reveals how fructose in diet enhances tumor growth

Fructose consumption has increased considerably over the past five decades, largely due to the widespread use of high-fructose corn syrup as a sweetener in beverages and ultra-processed foods.

New research  shows that dietary fructose promotes tumor growth in animal models of melanoma, breast cancer and cervical cancer. However, fructose does not directly fuel tumors, according to the study published Dec. 4 in the journal Nature.

Scientists discovered that the liver converts fructose into usable nutrients for cancer cells, a compelling finding that could open up new avenues for care and treatment of many different types of cancer.

Using metabolomics—a method of profiling small molecules as they move through cells and across different tissues in the body—the researchers concluded that one way in which high levels of fructose consumption promote tumor growth is by increasing the availability of circulating lipids in the blood. These lipids are building blocks for the cell membrane, and cancer cells need them to grow.

Researchers looked at numerous different cancers in various tissues throughout the body, and they all followed the same mechanism.

Scientists have long recognized that cancer cells have a strong affinity for glucose, a simple sugar that is the body's preferred carbohydrate-based energy source.

In terms of its chemical structure, fructose is similar to glucose. They are both common types of sugar, with the same chemical formula, but they differ in how the body metabolizes them. Glucose is processed throughout the whole body, while fructose is almost entirely metabolized by the small intestine and liver.

Both sugars are found naturally in fruits, vegetables, dairy products and grains. They are also added as sweeteners in many processed foods. 

 The researchers found that added fructose promoted tumor growth without changing body weight, fasting glucose or fasting insulin levels. It had a rather dramatic impact. In some cases, the growth rate of the tumors accelerated by two-fold or even higher.

The researchers attempted to repeat a version of this test by feeding fructose to cancer cells isolated in a dish, the cells did not respond. In most cases they grew almost as slowly as if we gave them no sugar at all.

Part 1

Comment by Dr. Krishna Kumari Challa on December 4, 2024 at 11:40am

Toxin in blood of kidney disease patients could contribute to stroke risk, study suggests

Scientists have revealed that a toxin found in the blood of patients with chronic kidney disease (CKD) damages the body's protective blood–brain barrier, likely contributing to the risk of stroke.

Researchers investigated the effect on the central nervous system of "p-cresol sulfate," a molecule produced by the gut microbiome. 

While this molecule is efficiently cleared by the kidneys in healthy people, it accumulates in the blood of patients with CKD.
Investigating the effect of p-cresol sulfate on human tissue and in mice—and replicating their results using blood samples from dialysis patients—the team found that the toxin triggers a process which activates two enzymes that damage the wall of brain blood vessels.

The researchers observed how this impairs the critically protective blood–brain barrier, which acts as a shield to prevent harmful substances and toxins in the body from reaching the brain.

Damage to the blood–brain barrier is known to contribute to the risk of stroke, which can be up to 30 times greater in CKD patients than in the general population.

As part of the study, however, the researchers also found that a class of 'inhibitor' type drugs—which can block chemical reactions in the body—showed promising results in being able to prevent this damage from occurring.

In further tests, the team found that a class of enzyme inhibitor drugs was able to block the damaging effects of blood from CKD patients on cells in vitro.

As well as enhanced stroke risk, patients with CKD, including those not yet requiring dialysis, exhibit significant cognitive decline, a change that seems to be at least partly driven by damage to the brain's blood vessels.

 Sita N. Shah et al, Cerebrovascular damage caused by the gut microbe/host co-metabolite p -cresol sulfate is prevented by blockade of the EGF receptor, Gut Microbes (2024). DOI: 10.1080/19490976.2024.2431651

Comment by Dr. Krishna Kumari Challa on December 4, 2024 at 10:39am

Seeing through the mystery of an X-ray emissions mechanism

Scientists who study X-rays, lightning and similar phenomena have observed something curious: In lab experiments replicating these occurrences, electrons accelerated between two electrodes can be of a higher energy than the voltage applied.

This defies an assumption in physics that the energy of the electrons should correspond with the voltage applied.

Recently, a team of  researchers used mathematical modeling to explain the underlying mechanism at play. They published their results in Physical Review Letters.

Through mathematical modeling, they  demonstrated that an energy feedback process is responsible for this occurrence.

According to them when the electrons interact with the material of the electrode, they emit X-rays, which are made of photons—massless, charge-less particles that comprise light. Some of these photons propagate backward, enabling more electrons to release from the other electrode.

A small group of these electrons have energy corresponding to the original energy. Then they accelerate again, and the process continues through several cycles. The researchers modeled this very high energy process.

Their model also helped explain why electrodes of different shapes and materials produced this effect to varying degrees. We get maximum effect when we have flat electrodes, and a minimized effect when the electrodes are needle-like. 

This makes sense, because the large surface areas of the flat electrodes are good for the interaction between the electrons and photons and the way they bounce back and forth. When the surface area is reduced, the effect is minimized.

The researchers also examined via simulation and modeling how the phenomenon emerges with different materials.

Tungsten is the standard material used for X-ray production, and we know it's a good material for this. It is a robust material for electron production used in current in X-ray machines.

The researchers said that their findings may be useful for the development of new ways of producing X-rays in the future. Specifically, they said that the work may stimulate new research on the production of energetic electrons from solid materials, potentially making X-rays machines faster and more light weight and compact.

Victor P. Pasko et al, Photoelectric Feedback Mechanism for Acceleration of Runaway Electrons in Gas Discharges at High Overvoltages, Physical Review Letters (2024). DOI: 10.1103/PhysRevLett.133.235301

Comment by Dr. Krishna Kumari Challa on December 4, 2024 at 10:15am

Countdown to an ice-free Arctic: Research warns of accelerated timelines

The first summer on record that melts practically all of the Arctic's sea ice, an ominous milestone for the planet, could occur as early as 2027.

For the first time, an international research team used computer models to predict when the first ice-free day could occur in the northernmost ocean. An ice-free Arctic could significantly impact the ecosystem and Earth's climate by changing weather patterns. 

The first ice-free day in the Arctic won't change things dramatically, the team says. It will show that we've fundamentally altered one of the defining characteristics of the natural environment in the Arctic Ocean, which is that it is covered by sea ice and snow year-round, through greenhouse gas emissions.

The findings were published Dec. 3 in the journal Nature Communications. Jahn will also present the results on Dec. 9 at the American Geophysical Union annual meeting in Washington D.C.

The researchers' projected/estimated the first ice-free Arctic day using output from over 300 computer simulations. They found that most models predicted that the first ice-free day could happen within nine to 20 years after 2023, regardless of how humans alter their greenhouse gas emissions. The earliest ice-free day in the Arctic Ocean could occur within three years.
It's an extreme scenario but a possibility based on the models. In total, nine simulations suggested that an ice-free day could occur in three to six years.

The researchers found that a series of extreme weather events could melt two million square kilometers or more of sea ice in a short period of time: A unusually warm fall first weakens the sea ice, followed by a warm Arctic winter and spring that prevents sea ice from forming. When the Arctic experiences such extreme warming for three or more years in a row, the first ice-free day could happen in late summer.

Those kinds of warm years have already happened.

But there's also good news: A drastic cut in emissions could delay the timeline for an ice-free Arctic and reduce the time the ocean stays ice-free, according to the study.

Céline Heuzé et al, The first ice-free day in the Arctic Ocean could occur before 2030, Nature Communications (2024). DOI: 10.1038/s41467-024-54508-3 , dx.doi.org/10.1038/s41467-024-54508-3

Comment by Dr. Krishna Kumari Challa on December 4, 2024 at 9:56am

Following this, daily solar radiation was the second most important factor contributing to rice quality changes (higher solar radiation leading to lower HRR), then daily precipitation (less precipitation corresponding to lower HRR) and lastly daytime vapor pressure deficit (beyond a threshold of 0.5–1 kPa, HRR declines).
The average rice quality across all sites and years for China had a HRR of ~62%, but reduced by 1.45% every decade. In Japan, the average HRR was slightly higher at ~66%, with a prominent rate of decline of 7.6% every decade.

In both countries, there is a strong gradient of diminished rice quality from northern to southern provinces and prefectures, likely linked to southern regions being closer to the equator and therefore experiencing higher nighttime temperatures.
This research is important as projections under both moderate and high emissions scenarios suggest rice quality will continue to decline in the decades to come as climate change progresses.
Given all of this, the likelihood of rice cultivars adapting in tandem with the rate of climate change may pose a hazard to sustainable food supplies, human nutrition and economic stability in years to come.

Xianfeng Liu et al, Warming Leads to Lower Rice Quality in East Asia, Geophysical Research Letters (2024). DOI: 10.1029/2024GL110557

Part 2

Comment by Dr. Krishna Kumari Challa on December 4, 2024 at 9:53am

Climate warming is reducing rice quality

Rice is a food staple for billions of people worldwide, with demand doubling over the past 50 years, and is predominantly grown in Asia before being exported globally. This crop is sensitive to weather conditions and, as such, understanding how yields are affected by climate change is of paramount importance to ensure sustainable food supplies into the future.

Beyond yield, the quality of rice may also be affected, determined by a combination of appearance, palatability, nutritional profile and milling properties.

Research published in Geophysical Research Letters, has highlighted a decline in rice quality in  Asia, coincident with changing temperatures.

Researchers used data collected over 35 years to explore patterns in rice quality from Japan and China. This is based upon head rice rate (HRR), which is a measure of the fraction of milled rice kernels that retain 75% of their length after milling, during which the husk and bran are removed.
The research team explored a number of climate variables via modeling to ascertain which had the greatest effect on HRR; these variables were nighttime temperature, daytime temperature, diurnal temperature, daily averaged temperature, hot days (above 30/35 °C), precipitation, precipitation frequency, soil moisture, solar radiation, cloud cover, relative humidity, daytime vapor pressure deficit, transpiration and carbon dioxide concentration.

Ultimately, the scientists determined that overnight temperatures are the main driver of reduced rice quality. In particular, as nighttime temperatures become warmer, a critical threshold for decline begins at 12 °C and 18 °C for Japan and China respectively. When flowering and grain growth occur in such conditions, rates of photosynthesis and starch accumulation in the grain decrease, leading to lower rice quality as more grains are susceptible to breakage.

Part 1

Comment by Dr. Krishna Kumari Challa on December 3, 2024 at 12:32pm

Galleri blood test can  help diagnose multiple forms of cancer

Did you know that the technology to detect more than 50 cancers with one test existed?

Single-cancer screenings are the norm. The focus is usually on three specific cancers in women (breast, colon and cervical) and two in men (prostate and colon). Lung is a focus for heavy smokers.

Screening for these cancers helps save lives. But it creates what Ofman calls a classic spotlight problem, shining the light over there while other, more aggressive cancers go unscreened.

The Galleri test doesn't target a specific area. It looks for the fingerprint, the biological signal in DNA that has been shed from cancer. It's a very specific marker and detects where that cancer is in the body.

It creates a more effective and efficient screening programme.

And unlike other cancer tests (10%) the false positive rate of the Galleri test is just 0.5%.

Source: Medical news

Comment by Dr. Krishna Kumari Challa on December 3, 2024 at 12:26pm

Countertop workers exposed to serious lung disease

Durable and attractive, engineered stone countertops are a popular feature in modern  kitchens, but the workers who build them are risking their health. A growing number of these countertop workers are developing silicosis, a serious and long-term lung disease, according to a study presented at the annual meeting of the Radiological Society of North America (RSNA).

This is a new and emerging epidemic, and we must increase awareness of this disease process so we can avoid delays in diagnosis and treatment for our patients, say the study authors.

Silicosis is caused by the inhalation of crystalline silica dust produced in construction, coal mining and other industries. The prognosis is poor, with gradually worsening lung function leading to respiratory failure. The disease also makes patients more vulnerable to infection in the lungs, chronic obstructive pulmonary disease, autoimmune disease and lung cancer.

In recent years, a resurgence of silicosis has been reported in engineered countertop workers. Engineered stone countertops are made from quartz aggregate held together with a resin binder. They contain substantially more crystalline silica than natural stone versions. Workers who cut, shape, grind and polish these countertops may be exposed to significant amounts of silica dust.

In a preliminary analysis of 21 workers, 100% were male and Hispanic with a median age of 43 years and a median exposure of 18 years. All patients were symptomatic. Patients commonly had atypical and advanced features of silicosis. Shortness of breath and cough were the most common symptoms.

Primary clinicians recognized silicosis at the initial encounter in only four of 21 cases (19%), while radiologists recognized it in seven of 21 cases (33%). Alternative diagnoses, such as infection, were initially suggested in most cases. Nearly half of the patients (48%) had atypical imaging features.

The results highlight a need for more awareness and better recognition of imaging features associated with silicosis.

Source: https://www.rsna.org/annual-meeting

Comment by Dr. Krishna Kumari Challa on December 3, 2024 at 12:21pm

Scientists discover a natural flu defense mechanism that activates in the nasal cavity during pregnancy

Scientists have discovered that pregnancy may trigger a natural immunity to boost protection against severe flu infection. Their work is published in the journal Science Advances.

Contrary to the common belief that pregnancy increases vulnerability to infections, researchers found that it strengthened an immune defense in mice, blocking the Influenza A virus from spreading to the lungs, where it can cause severe infection.

A mother needs to stay healthy to protect her developing baby, so the immune system adapts to provide stronger defenses. This fascinating response in the nasal cavity  is the body's way of adding an extra layer of protection, which turns on during pregnancy.

The researchers used a mouse model to observe how a certain type of immune cell activates in the nasal cavity of mice during pregnancy, producing a powerful molecule that boosts the body's antiviral defenses, especially in the nose and upper airways.

This natural immunity in pregnancy could change the way we think about flu protection for expectant mothers

Julia Chronopoulos et al, Pregnancy enhances antiviral immunity independent of type I IFN but dependent on IL-17–producing γδ + T cells in the nasal mucosa, Science Advances (2024). DOI: 10.1126/sciadv.ado7087

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