What Are The Effects of Temperature, Impact Velocity & Impactor Density On Crater Shape? (Planetary Science)

Iron meteorites are composed of iron-nickel alloys and classified structurally into hexahedrites (5–6.5 wt% Ni), octahedrites (6–12 wt% Ni), and ataxites (~10 to >20 wt% Ni). Iron meteorites are also classified chemically in terms of the concentrations of trace elements, for example Ge and Ga, into several groups. Comparisons of the chemical trends within groups suggest that there are two different types: magmatic and non-magmatic. Magmatic groups are thought to be derived from the metallic cores of differentiated bodies whereas non-magmatic groups may come from bodies that were not heated enough to form metallic cores. The cores formed in the parent bodies of magmatic iron meteorites less than ~1.0 Myr after the formation of calcium-, aluminum-rich inclusions (CAIs), whereas chondrule ages are about 2–4 Myr after CAIs.

In 2006, Bottke et al. suggested that the parent bodies of iron meteorites are considered to have formed early in the terrestrial planet region before migrating to the main asteroid belt by gravitational interactions with protoplanets. Asteroid 16 Psyche is the largest metal-rich asteroid in the main asteroid belt, measuring 232×189×279 km, and might be such a remnant. The equilibrium temperature of the iron meteorites’ parent bodies decreased from about 300 K to 160 K during migration from the terrestrial planet region to the main asteroid belt. Some iron meteorites undergo a transition from ductile to brittle behavior as the temperature decreases. Moreover, the most probable collision velocity in the main asteroid belt is 4.4 km/s, however, it could have been higher in the terrestrial planet region early in the solar system. Such a velocity difference may also cause a difference in crater shape on metallic bodies.

Now, Ogawa and colleagues conducted impact experiments on room- and low-temperature iron meteorite and iron alloy targets (carbon steel SS400 and iron-nickel alloy) with velocities of 0.8–7 km s¯1, using a two-stage hydrogen-gas gun installed at the Institute of Space and Astronautical Science (ISAS) and a vertical powder gun at Kobe University, to investigate the dependence of crater shape on temperature, velocity and impactor density.

Figure 1. Cross-sections of the craters formed by copper projectiles (a) at room temperature with a velocity of 2.38 km s¯1 (Sc1), at low temperature (b) with velocities of 2.14 km s¯1 (Sc6), and (c) 6.08 km s¯1 (Sc9). © Nakamura et al.

The projectiles were rock cylinders and metal spheres and cylinders. They also conducted Oblique impact experiments using stainless steel projectiles and SS400 steel targets which produced more prominent radial patterns downrange at room temperature than at low temperature. Crater diameters and depths were measured and compiled using non-dimensional parameter sets based on the π -group crater scaling relations. They also performed iSALE-2D simulations using the Johnson– Cook (JNCK) strength model assuming JNCK parameters for the Gibeon iron meteorite, SS400 and SUS304.

The laboratory and numerical results collectively show that the depth/diameter (d/D) values of metallic targets are more dependent on velocity (U) than are those of rocky targets. The ratio is smaller under low velocity and low-temperature conditions; however, the ratio is more sensitive to U than it is to the temperature of the target.”

— told Nakamura, author of the study

Both experimental and numerical results showed that the crater depth and diameter decreased with decreasing temperature, which strengthened the target, and with decreasing impact velocity. The decreasing tendency was more prominent for depth than for diameter, i.e., the depth/diameter (d/D) ratio was smaller for the low temperature and low velocity conditions. The depth/diameter ratios of craters formed by rock projectiles were shallower than those of craters formed by metallic projectiles. Their results imply that the d/D values of craters on metallic surfaces contain information about the past impact environment of metallic bodies.

Featured image: The definitions of crater diameter, crater depth and rim height used in this study. On the left is the numerical result and on the right is the experimental result for an SUS-Gibeon 5.1-km/s impact (Gs4). The black and gray parts of the numerical result represent the projectile and target materials, respectively © Nakamura et al.


Reference: Ryo Ogawa, Akiko M. Nakamura, Ayako Suzuki, Sunao Hasegawa, “Crater shape as a possible record of the impact environment of metallic bodies: Effects of temperature, impact velocity and impactor density”, ArXiv, pp. 1-63, 4 Mar 2021. https://arxiv.org/abs/2103.03128


Copyright of this article totally belongs to our author S. Aman. One is allowed to reuse it only by giving proper credit either to him or to us

No Eyes? No Problem. Worms Still Avoid the Blues (Biology)

Worms don’t like the blues. At least not the blue-tinged toxic bacteria that are common in the environmental trash heaps they call home. So how does a bacteria-foraging worm — without eyes, photoreceptors, or the opsin genes that help animals perceive color — avoid the toxic, blue-reflecting bacterium Pseudomonas aeruginosa?

Until recently, Yale’s Michael Nitabach thought worms must recognize distinct chemical chemosensory odors emitted by this bacterium. D. Dipon Ghosh, a former graduate student in Nitabach’s lab, wondered if worms could also have the capacity to somehow sense colors.

“I told him he was being ridiculous,” said Nitabach, professor of cellular and molecular physiology, of genetics and of neuroscience.

Turns out Ghosh was right. In the March 5 issue of the journal Science, Nitabach and Ghosh report how worms manage to detect color in complete absence of a basic visual system.

This discovery expands our current ideas about the possible range of sensitivities that cells and organisms — even those that lack the proteins required for vision — might have to light in their environment.

In a series of experiments, the research team exposed different strains of the worm Caenorhabditis elegans to either the colorful P. aeruginosa bacteria in white light or to colorless E. coli bacteria in light of varying color spectra. They found that while some family members require both a chemical signaling toxic bacteria and a specific color to decide to avoid the bactera, others avoid the bacteria based on color alone. In both cases, the worm’s decision on whether to avoid the bacteria was guided by the color of light in its environment.

The lab also identified two genes in worms that are associated with the ability to gauge color. In mammals, these same genes help regulate the response to stress and can be activated by exposure to ultraviolet light.

“What the worm is doing is something very smart,” Nitabach said. “They are trying to generate a more accurate picture of external reality by employing multiple senses at same time.”

The researchers speculate that this ability helps worm engage in healthy foraging. For example, for worms that have been exposed to toxic bacteria that secrete blue pigments, avoiding the blues might be a really good idea.


Reference: D. Dipon Ghosh, Dongyeop Lee, Xin Jin, H. Robert Horvitz, Michael N. Nitabach, “C. elegans discriminates colors to guide foraging”, Science 05 Mar 2021: Vol. 371, Issue 6533, pp. 1059-1063 DOI: 10.1126/science.abd3010


Provided by Yale news

Is Bitcoin a Bubble? (Finance)

The price of a single Bitcoin reached a peak of $57,489 on February 21, and remains up more than 700% since the beginning of 2020, defying years of predictions of a crash. Newly created exchange-traded funds backed by Bitcoin are drawing more investment. We asked Yale economist Aleh Tsyvinski to shed some light on the continuing phenomenon.

Why is bitcoin still going up? Is it a bubble?

One can say that any fiat money—that is, money that isn’t backed by a commodity like gold or silver—is a bubble. At the same time, economists are terrible at identifying and even modeling bubbles. My research with Yukun Liu from the University of Rochester gives one explanation for why it may be going up. Two factors which may be behind it are momentum and the attention that people pay to it. Momentum means that if bitcoin went up more than usual it will on average continue to go up. Similarly, if there are more, for example, Google searches on the word bitcoin, bitcoin prices tend to go up.

Are the energy and environmental impacts of bitcoin likely to constrain its continued growth?

Yukun and I find that electricity prices and consumption in the short run are not one of the factors that determine bitcoin prices. However, environmental impact is something that we should all be concerned about.

A decade in, has bitcoin made a case for why we need digital currencies?

It is important to distinguish digital currencies and blockchain technology, the distributed ledger that records bitcoin transactions. Even if one does not like crypto currencies, there is no doubt that blockchain technology created a new and important area of innovation. 

Featured image: Bitcoin floating in a Bubble on a black background © Marko Aliaksandr/Shutterstock


Reference: Liu, Yukun and Tsyvinski, Aleh, Risks and Returns of Cryptocurrency (August 6, 2018). Available at SSRN: https://ssrn.com/abstract=3226952 or http://dx.doi.org/10.2139/ssrn.3226952


Provided by Yale news

Swansea University Developing World’s First COVID-19 ‘Smart-Patch’ Vaccine That Will Measure Effectiveness (Medicine)

Researchers at Swansea University are developing the world’s first smart vaccine device that will both deliver the COVID-19 vaccine and measure its efficacy through monitoring the body’s associated response.

The research, from the Institute for Innovative Materials, Processing and Numerical Technologies (IMPACT), will produce the vaccine through the use of microneedles (MNs) to create a ‘smart-patch’. This device will simultaneously measure a patient’s inflammatory response to the vaccination by monitoring biomarkers in the skin.

Microneedles are tiny needles – their tips are measured in millionths of a metre (micrometer) – designed to break the skin barrier and deliver medicines in a minimally invasive manner. A classic example is the transdermal nicotine patch that delivers nicotine through skin to help people give up smoking.

Microneedles provide a safe and effective method to deliver vaccines with added attributes of requiring lower vaccine doses, permitting low-cost manufacturing, and enabling simple distribution and administration. A microneedle delivery patch is easy to apply and minimally invasive – combined with the proposed measurement capabilities, this new vaccine system would enable a personalised vaccination approach.

Project lead Dr Sanjiv Sharma of Swansea University comments:

“Measuring vaccine efficacy is extremely important as it indicates the protective effects of vaccination on an individual via the level of reduction of infection risk in a vaccinated person relative to that of a susceptible, unvaccinated individual. This measure of vaccination effectiveness will address an unmet clinical need and would provide an innovative approach to vaccine development.”

The project, titled Smart vaccine devices for delivery of COVID-19 vaccination, will be led by a team of researchers with expertise in the use of microneedle arrays for transdermal therapeutic drug delivery and diagnostic applications.

The team will build on these distinct technologies by developing the first dual functionality microneedle-based COVID-19 smart-patch, capable of delivering a vaccine and measuring the immune response in the form of protein biomarkers thus establishing the efficacy of vaccination.

Dr Sharma continues:

“Skin vaccination using MNs has been described as a superior immunization approach due to its potential to overcome immune tolerance observed in pregnancy, and lower vaccination costs through antigen dose-sparing, which is especially relevant in underserved countries.

The primary goal of this project is to create a prototype of smart vaccine delivery device that can not only deliver the COVID-19 vaccine transdermally but also monitor biomarkers in the skin compartment in a minimally invasive way, offering real-time information on the efficacy of the vaccination. The new method would change the way in which vaccine efficacy trials are performed from a statistical assessment to a scientific measurement of patient inflammatory response to vaccination.

The real-time nature of the platform will mean rapid results allowing faster containment of the COVID-19 virus. This low-cost vaccine administration device will ensure a safe return to work and management of subsequent COVID-19 outbreak waves. Beyond the pandemic, the scope of this work could be expanded to apply to other infectious diseases as the nature of the platform allows for quick adaptation to different infectious diseases.

We are currently getting the platform ready and we hope to do human clinical studies on transdermal delivery with our existing partners at Imperial College London, in preparation for final implementation.”

A team led by Professor Nikolaj Gadegaard of the University of Glasgow’s James Watt School of Engineering have developed an injection-moulding process to enable large-scale production of the microneedle smart patches. They have already made around 5,000 patches to help support Dr Sharma’s research and expect to produce many thousands more to allow the clinical studies to progress.

The project is funded by the Welsh Government Sêr Cymru funding programme. The IMPACT operation is part-funded by the European Regional Development Fund through the Welsh Government and Swansea University.

Featured image: Close-up of a microneedle (top) compared to a hypodermic needle, showing how microneedles are far less invasive © Swansea University


This science news is confirmed by us from Swansea University


Provided by Swansea University

New Method Facilitates Development of Antibody-based Drugs (Medicine)

In recent years, therapeutic antibodies have transformed the treatment of cancer and autoimmune diseases. Now, researchers at Lund University in Sweden have developed a new, efficient method based on the genetic scissors CRISPR-Cas9, that facilitates antibody development. The discovery is published in Nature Communications.

Antibody drugs are the fastest growing class of drug, and several therapeutic antibodies are used to treat cancer. They are effective, often have few side effects and benefit from the body’s own immune system by identifying foreign substances in the body. By binding to a specific target molecule on a cell, the antibody can either activate the immune system, or cause the cell to self-destruct.

However, most antibody drugs used today have been developed against an antibody target chosen beforehand. This approach is limited by the knowledge of cancer we have today and restricts the discovery of new medicines to currently known targets.

”Many antibody drugs currently target the same molecule, which is a bit limiting. Antibodies targeting new molecules could give more patients access to effective treatment”, says Jenny Mattsson, doctoral student at the Department of Hematology and Transfusion Medicine at Lund University.

Another route – that pharmaceutical companies would like to go down – would be to search for antibodies against cancer cells without being limited to a pre-specified target molecule. In this way, new, unexpected target molecules could be identified. The problem is that this method (so-called “phenotypic antibody development”) requires that the target molecule be identified at a later stage, which has so far been technically difficult and time-consuming.

”Using the CRISPR-Cas9 gene scissors, we were able to quickly identify the target molecules for 38 of 39 test antibodies. Although we were certain that the method would be effective, we were surprised that the results would be this precise. With previous methods, it has been difficult to find the target molecule even for a single antibody”, says Jenny Mattsson.

The research project is a collaboration between Lund University, BioInvent International and the Foundation for Strategic Research. The researchers’ method has already been put into practical use in BioInvent’s ongoing research projects.

”We believe the method can help antibody developers and hopefully contribute to the development of new antibody-based drugs in the future”, concludes Professor Björn Nilsson, who led the project.

Featured image: The structure of an antibody © Lund University


Publication:

Link to article in Nature Communications: Accelerating target deconvolution for therapeutic antibody candidates using highly parallelized genome editing


Provided by Lund University

Ambulatory Function Among Cancer Survivors May be an Important Determinant for Survival (Medicine)

Cancer survivors had a greater risk of reduced ambulatory function, which was associated with an increased risk of death, according to a study published in Cancer Epidemiology, Biomarkers & Prevention, a journal of the American Association for Cancer Research.

The diagnosis and treatment of cancer has been shown to be associated with poor functional health for common cancer types, such as those of the breast and prostate, but less is known about the association for other cancers, explained Elizabeth Salerno, PhD, MPH, assistant professor of surgery at Washington University School of Medicine in St. Louis, who conducted the research at the National Cancer Institute. “Given that cancer survivors are living longer than ever, understanding how the diagnosis and treatment of a broad range of cancers may affect ambulatory function—a potentially modifiable risk factor—could lead to new treatment and rehabilitation strategies to improve the health of these patients,” she explained.

In this study, Salerno and colleagues examined whether reduced ambulatory function was linked to various cancer types, and whether ambulatory function was associated with survival. Salerno and colleagues examined data from the National Institutes of Health American Association of Retired Persons (AARP) Diet and Health Study, which included over 500,000 AARP members between the ages of 51 and 70. AARP members received a questionnaire assessing demographics, medical history, and diet between the years of 1995 and 1996 and a follow-up questionnaire between 2004 and 2006 assessing health status, lifestyle, and ambulatory function, among other factors. Ambulatory function was determined by self-reported walking pace and mobility disability.

After excluding individuals for reporting inaccuracies and incomplete questionnaires, the final sample included 30,403 cancer survivors and 202,732 individuals who had never been diagnosed with cancer. The median age of participants was 61.8 years, and most individuals identified as white (92.4 percent), male (56.7 percent), and in very good health (56.4 percent). A broad range of cancer types was represented in the study population, including cancers of the breast, respiratory system, lymphatic system, skin, genitourinary tract, and gastrointestinal tract, among others.

Salerno and colleagues found that cancer survivors were 42 percent more likely to report walking at the slowest pace compared to individuals without a cancer diagnosis. After adjusting for demographics, health status, cancer type, and body mass index, cancer survivors also had a 24 percent greater risk of mobility disability. Lower ambulatory function was associated with several cancer types, and the strongest associations were observed for survivors of respiratory or oral cancers.

Slower walking pace and mobility disability were also associated with increased risk for all-cause and cancer-specific mortality in cancer survivors after adjusting for demographics and cancer characteristics. Survivors who reported walking at the slowest pace had over twofold increased risk of both all-cause and cancer-specific mortality compared with survivors who reported a brisk walking pace. Similarly, survivors with mobility disability had 80 percent and 64 percent greater risk of all-cause and cancer-specific mortality, respectively.

While slower walking pace and mobility disability also increased mortality risk in individuals without cancer, Salerno and colleagues found that the association between ambulatory function and mortality was greater for cancer survivors than for individuals without cancer. When compared with individuals without a cancer diagnosis who reported a brisk walking pace, cancer survivors who had the slowest walking pace had over 10-fold increased risk of death; those without cancer with the slowest walking pace had over threefold increased risk of death.

“Our findings suggest that functional health may be adversely affected by a broad range of cancer diagnoses and may be an important determinant for survival,” said Salerno. “There is still much to be learned about these complex relationships, but our results highlight the potential importance of monitoring, and even targeting, ambulatory function after cancer for survival benefits, particularly in older cancer survivors.”

Future research from Salerno and colleagues will aim to understand why certain cancers had more robust associations with ambulatory function and stronger associations between ambulatory function and mortality. “More information about behavioral, biological, and cancer-specific factors from before, during, and after diagnosis and treatment will be important to better characterize these associations in specific cancer types,” she said.

A limitation of the study is that all data on walking pace and mobility disability were self-reported. While self-reporting is important for collecting widespread surveillance data, it may not be as precise as clinical measures, Salerno explained. In the future, Salerno is interested in examining the correlation between self-reported ambulatory function and more objective measures in the context of cancer and mortality. Additional limitations include the lack of comprehensive treatment data, the fact that the survivor population was relatively healthy and had mostly early-stage disease, and the potential for additional confounding variables not controlled for in the analyses.

The study was supported by the Intramural Research Program of the National Cancer Institute, part of the National Institutes of Health. Salerno declares no conflicts of interest.


Reference: Elizabeth A. Salerno, Pedro F. Saint-Maurice, Erik A. Willis, Steven C. Moore, Loretta DiPietro and Charles E. Matthews, “Ambulatory Function and Mortality among Cancer Survivors in the NIH-AARP Diet and Health Study”, Cancer Epidemiol Biomarkers Prev March 4 2021 DOI: 10.1158/1055-9965.EPI-20-1473


Provided by AACR

Researchers Reveal Process Behind Harmful Glial Cell Change in Motor Neurone Disease (Neuroscience)

Scientists at the Francis Crick Institute and UCL have identified the trigger of a key cellular change in amyotrophic lateral sclerosis (ALS), a type of motor neurone disease. The findings could help develop new treatments for many neurological diseases with the same change, including Parkinson’s and Alzheimer’s.  

When the nervous system is injured, diseased or infected, star-shaped cells, called astrocytes, undergo ‘reactive’ changes in their behaviour. Whilst some of these reactive astrocytes become protective, others become harmful and damage surrounding motor neurons. 

Reactive astrocytes are observed in various neurodegenerative diseases including ALS, but there is a lack of understanding about what causes astrocytes to undergo this change. 

In their research, published in Nucleic Acids Research, the scientists compared ALS-diseased astrocytes with healthy astrocytes to uncover how the diseased cells become reactive. These cells were grown from human induced pluripotent stem cells – master stem cells – which can be directed to differentiate into any cell in the human body.

“Understanding how astrocytes undergo this transformation is a really exciting step forward. It brings us closer to potentially being able to control and prevent astrocytes from becoming harmfully reactive.”

—  Rickie Patani

They found that key to the astrocyte change in diseased cells is an increase in the removal of introns (non-coding sections of genetic information) from RNA in a process called splicing.  The team identified that in healthy astrocytes there are some RNAs that normally retain certain introns however in diseased cells these particular introns are spliced out. 

This has dramatic consequences on the cell’s actions as when these introns are cut out of RNA, the remaining exons (coding sections of genetic information) are used as a recipe for building proteins and some of these proteins play a role in the astrocytes changing. 

Rickie Patani, senior author, group leader at the Crick, Professor at UCL’s Queen Square Institute of Neurology and a consultant neurologist at the National Hospital for Neurology and Neurosurgery, says: “Understanding how astrocytes undergo this transformation is a really exciting step forward. It brings us closer to potentially being able to control and prevent astrocytes from becoming harmfully reactive. While there’s still a long way to go, we’re hopeful that developing such a treatment is possible and that it could even potentially be used across all neurological conditions in which an increase in reactive astrocytes is also documented, including Parkinson’s and Alzheimer’s.”

ALS is a rapidly progressing degenerative disease. Patients commonly suffer loss of movement, speech and eventually the ability to breathe, and most people only live 3 to 5 years after diagnosis. There are currently no treatments that can meaningfully alter the prognosis. 

But understanding key cellular changes associated with ALS could help develop new therapies to slow disease progression.

Oliver Ziff, lead author and clinical fellow at the Crick, UCL’s Queen Square Institute of Neurology and a neurology registrar at the National Hospital for Neurology and Neurosurgery, says: “Our group have previously shown that splicing is decreased in ALS motor neurons, so when we found the opposite in ALS astrocytes we were intrigued. In fact, increased splicing is what we find in other immune cells when they become activated or angry. This raises the possibility that ALS astrocytes inflict a toxic immune insult on the nervous system and opens new therapeutic avenues for treating ALS.”   

The researchers will continue this work to further understand the molecular mechanisms involved when astrocytes become reactive with the ambition of developing an intervention that could be used by doctors to slow disease progression.  


Reference: Oliver J Ziff, Doaa M Taha, Hamish Crerar, Benjamin E Clarke, Anob M Chakrabarti, Gavin Kelly, Jacob Neeves, Giulia E Tyzack, Nicholas M Luscombe, Rickie Patani, Reactive astrocytes in ALS display diminished intron retention, Nucleic Acids Research, 2021;, gkab115, https://doi.org/10.1093/nar/gkab115


Provided by Francis Crick Institute

HIV Treatment Helps Prevent Active TB (Medicine)

Antiretroviral treatment (ART) reduces the risk of developing active tuberculosis (TB) in people also infected with HIV-1, by dampening the activation of the body’s immune response. These findings could help improve treatment for both conditions in the future.

“Our increased understanding of TB in people who also have HIV, could lead to improved treatments for both conditions.”

— Robert Wilkinson

TB remains to be the leading bacterial cause of death worldwide and co-infection with HIV is the biggest risk factor for developing an active infection. But it’s been observed that people taking ART are less likely to have a latent TB infection become active and potentially life threatening.

Researchers at the Francis Crick Institute and the Wellcome Centre for Infectious Diseases Research at the University of Cape Town, have been researching links between the two conditions for a number of years. In their latest study, published today (Friday) in Frontiers in Immunology, they took a 3-step approach to unpicking the connection.

Firstly, the team carried out a broader analysis of blood from individuals with both latent TB infection and HIV-1, during their first 6 months of ART. They observed a significant drop in the inflammatory signalling activity of immune cells. This was also confirmed by further analysis of plasma samples taken after 6 months of ART, which showed a decrease in the presence of inflammatory markers.

In the final step, the researchers focused in on 30 patients and carried out highly detailed multiplex analysis of their blood plasma to better understand the change in inflammatory markers. They found a consistent decrease in IL-1alpha and IL-1beta concentrations over time.

Collectively, their results show that the decreased risk of active TB can be explained by reduced inflammatory immune responses during treatment with ART.

Katalin Wilkinson, Principal Laboratory Research Scientist at the Crick and the University of Cape Town, and first author of the study, said: “Our study highlights the additional benefits of ensuring people with HIV get access to ART, especially in countries where prevalence of both infections is much higher.

“Now that we understand the biological mechanisms behind this connection, we can better inform treatments and prevention strategies for both conditions.”

This research project gained momentum after Katalin took the idea to the Crick data challenge, which brings together researchers from across the institute with experts from our Bioinformatics and Biostatistics and Scientific Computing Platforms in a hackathon-style event. She then presented early data at the institute’s annual Autumn Science Meeting, leading to more groups and facilities at the Crick lending their support and expertise.

The team will continue exploring the biology behind HIV and TB co-infection, including an interesting phenomenon they spotted as part of this study. They plan to look in more detail at an observed increase in the heme metabolism pathway, that could be linked to the endothelial disfunction (narrowing of large blood vessels on the heart’s surface) associated with HIV infection, as well as the increased risk of cardiovascular disease among people taking ART.

Robert Wilkinson, Group Leader of the Crick’s tuberculosis laboratory, said: “Our increased understanding of TB in people who also have HIV, could lead to improved treatments for both conditions.

“Long term dysregulation of the immune system can be damaging to many parts of the body, so treatments of the future should aim to tackle this so that we can effectively control TB and HIV with fewer side effects for people.”


Reference: Katalin A. Wilkinson, Deborah Schneider-Luftman, Rachel Lai et al., “Antiretroviral Treatment-Induced Decrease in Immune Activation Contributes to Reduced Susceptibility to Tuberculosis in HIV-1/Mtb Co-infected Persons”, Front. Immunol., 05 March 2021 | https://doi.org/10.3389/fimmu.2021.645446


Provided by Francis Crick Institute

First-of-its-kind Surgery Helping Patients With Lymphedema (Medicine)

Lymphedema is swelling that typically occurs in the extremities, often resulting from the damage or removal of a person’s lymph nodes during cancer treatment. It affects approximately 1 in every 1,000 Americans and is especially prevalent in patients with breast cancer. The swelling can cause discomfort and lead to infection.

Mayo Clinic surgeons in Arizona are leading the way with cutting-edge technology by using robotic surgery to offer a new procedure to treat lymphedema.

Watch: The Mayo Clinic Minute

Journalists: Broadcast-quality video pkg (1:05) is in the downloads at the end of the post. Please Courtesy: “Mayo Clinic News Network.” Read the script.

“One of the best areas to get lymph nodes for transplant or lymph nodes for transfer is actually from the omentum,” says Dr. Alanna Rebecca, a Mayo Clinic plastic surgeon.

The omentum is a membrane of fatty tissue that lines your abdominal cavity. Traditionally, a lymph node transfer in that area required laparoscopic surgery, a large incision, and any risks and postoperative side effects that might come with it.

But a team of surgeons at Mayo Clinic in Arizona is now performing the next generation of this type of surgery — a first-of-its-kind procedure using what’s called a single-port robot.

“We are the only institution in the world that has ever done this procedure,” says Dr. Rebecca.

“We make a 2.5- to 3-centimeter incision — just one incision — through which a single-port robot can then enter into the abdominal cavity and facilitate harvest of the omentum,” says Dr. Chad Teven, a Mayo Clinic plastic surgeon.

This new, minimally invasive procedure allows surgeons to be more precise and improve patient outcomes while relieving their lymphedema symptoms. 

“There are hundreds of thousands and potentially even millions of people who could benefit from these procedures,” says Dr. Rebecca.


Provided by Mayo Clinic