Tag: 28/6/22

Categories : Implants and ProsthesesTags :

Partially Paralysed Man Uses Robotic Arms to Feed Himself

On By ModernMedia
Photo by Tara Winstead on Pexels

Recent advances in neural science, robotics, and software have enabled scientists to develop a robotic system that responds to muscle movement signals from a partially paralysed person relayed through a brain-machine interface. Human and robot act as a team to make performing some tasks a piece of cake.

Two robotic arms – a fork in one hand, a knife in the other – flank a seated man, who sits in front of a table, with a piece of cake on a plate. A computerised voice announces each action: “moving fork to food” and “retracting knife.” Partially paralysed, the man makes subtle motions with his right and left fists at certain prompts, such as “select cut location”, so that the machine slices off a bite-sized piece. Now: “moving food to mouth” and another subtle gesture to align the fork with his mouth.

In less than 90 seconds, a person with very limited upper body mobility who hasn’t been able to use his fingers in about 30 years, just fed himself dessert using his mind and some smart robotic hands.

A team led by researchers at the Johns Hopkins Applied Physics Laboratory (APL), in Laurel, Maryland, and the Department of Physical Medicine and Rehabilitation (PMR) in the Johns Hopkins School of Medicine, published a paper in the journal Frontiers in Neurorobotics that described this latest feat using a brain-machine interface (BMI) and a pair of modular prosthetic limbs.

Also sometimes referred to as a brain-computer interface, BMI systems provide a direct communication link between the brain and a computer, which decodes neural signals and ‘translates’ them to perform various external functions, from moving a cursor on a screen to now enjoying a bite of cake. In this particular experiment, muscle movement signals from the brain helped control the robotic prosthetics.

A new approach

The study built on more than 15 years of research in neural science, robotics, and software, led by APL in collaboration with the Department of PMR, as part of the Revolutionizing Prosthetics program, which was originally sponsored by the US Defense Advanced Research Project Agency (DARPA). The new paper outlines an innovative model for shared control that enables a human to manoeuvre a pair of robotic prostheses with minimal mental input.

“This shared control approach is intended to leverage the intrinsic capabilities of the brain machine interface and the robotic system, creating a ‘best of both worlds’ environment where the user can personalise the behaviour of a smart prosthesis,” said Dr Francesco Tenore, a senior project manager in APL’s Research and Exploratory Development Department. The paper’s senior author, Tenore focuses on neural interface and applied neuroscience research.

“Although our results are preliminary, we are excited about giving users with limited capability a true sense of control over increasingly intelligent assistive machines,” he added.

Helping people with disabilities

One of the most important advances in robotics demonstrated in the paper is combining robot autonomy with limited human input, with the machine doing most of the work while enabling the user to customize robot behavior to their liking, according to Dr David Handelman, the paper’s first author and a senior roboticist in the Intelligent Systems Branch of the Research and Exploratory Development Department at APL.

“In order for robots to perform human-like tasks for people with reduced functionality, they will require human-like dexterity. Human-like dexterity requires complex control of a complex robot skeleton,” he explained. “Our goal is to make it easy for the user to control the few things that matter most for specific tasks.”

Dr Pablo Celnik, project principal investigator in the department of PMR said: “The human-machine interaction demonstrated in this project denotes the potential capabilities that can be developed to help people with disabilities.”

Closing the loop

While the DARPA program officially ended in August 2020, the team at APL and at the Johns Hopkins School of Medicine continues to collaborate with colleagues at other institutions to demonstrate and explore the potential of the technology.

The next iteration of the system may integrate previous research that found providing sensory stimulation to amputees enabled them to not only perceive their phantom limb, but use muscle movement signals from the brain to control a prosthetic. The theory is that the addition of sensory feedback, delivered straight to a person’s brain, may help him or her perform some tasks without requiring the constant visual feedback in the current experiment.

“This research is a great example of this philosophy where we knew we had all the tools to demonstrate this complex bimanual activity of daily living that non-disabled people take for granted,” Tenore said. “Many challenges still lie ahead, including improved task execution, in terms of both accuracy and timing, and closed-loop control without the constant need for visual feedback.”

Celnik added: “Future research will explore the boundaries of these interactions, even beyond basic activities of daily living.”

Source: Frontiers

Categories : HospitalsTags :

Physicians Prescribe Less Analgesic Medication during Nightshifts

On By ModernMedia
Photo by Mulyadi on Unsplash

Physicians prescribe less analgesic medication during nightshifts than during the day, according to a new study published in PNAS.

In the first part of the study, 67 doctors were given empathy assessment tasks in the morning and asked to respond to simulated patient scenarios. These doctors were either at the end of a 26-hour shift or just beginning their workday. The study found that doctors who recently completed night shift showed less empathy for patient’s pain. For example, these physicians’ exhibited decreased emotional responses to pictures of people in pain and consistently scored their patients low on pain assessment charts.

In the second part of the study, the researchers looked at actual medical decisions made by emergency room doctors in the United States and Israel. Analysed 13 482 discharge letters for patients who came to the hospital in 2013–2020 with a chief complaint of pain, they found that physicians were 20–30% less likely to prescribe an analgesic during nightshifts (compared to daytime shifts) and in amounts less than generally recommended by the World Health Organization. “They’re tired and therefore they’re less empathic to patients’ pain. When we looked at ER doctors’ discharge papers, we found that they prescribed fewer painkillers,” explained Professor Shoham Choshen-Hillel from the Hebrew University of Jerusalem (HU)’s School of Business Administration and Federmann Center for the Study of Rationality, who led the study.

The bias persisted after adjusting for patients’ reported level of pain, patient and physician’s demographics, type of complaint, and emergency department characteristics. “Our takeaway is that nightshift work is an important and previously unrecognised source of bias in pain management, likely stemming from impaired perception of pain. The researchers explain that even medical experts, who strive to provide the best care for their patients, are susceptible to the effects of a nightshift,” noted co-lead author HU Psychology Department’s Dr Anat Perry.

Looking ahead, the researchers suggest implementing more structured pain management guidelines in hospitals. Another important implication relates to physician work structure, and the need to improve physicians’ working schedules. “Our findings may have implications for other workplaces that involve shiftwork and empathic decision-making, including crisis centres, first responders, and the military. In fact, these results should probably matter to all people who are sleep-deprived,” added co-lead author Dr Alex Gileles-Hillel from Hadassah Medical Center and HU.

Source: ScienceDaily

Categories : Metabolic DisordersTags :

Cold Temperatures Could Reduce Obesity-induced Inflammation

On By ModernMedia
Photo by Ian Keefe on Unsplash

In a new paper published in Nature Metabolism, researchers found that cold temperature exposure resolved obesity-induced inflammation while improving insulin sensitivity and glucose tolerance in diet-induced obese mice. The process depended on brown adipose tissue producing a molecule called Maresin 2 when stimulated by cold.

Brown adipose tissue is known to be an active endocrine orgain which helps dissipate stored energy and might promote weight loss and metabolic health.  

“Extensive evidence indicates that obesity and metabolic syndrome are linked with chronic inflammation that leads to systemic insulin resistance, so interrupting inflammation in obesity could offer promising therapies for obesity-related disease,” said co-corresponding author Yu-Hua Tseng, PhD, professor of medicine at Harvard Medical School.  “We discovered that cold exposure reduced inflammation and improved metabolism in obesity, mediated at least in part by the activation of brown adipose tissue. These findings suggest a previously unrecognized function of brown adipose tissue in promoting the resolution of inflammation in obesity.”

In two previous studies, Tseng and colleagues discovered that cold exposure could activate brown fat to produce specific lipid mediators that regulate nutrient metabolism. In the current study, the researchers identified a novel role for a lipid mediator produced from brown fat to resolve inflammation.

In the present study, the scientists created a mouse model that becomes obese when fed a typical high-fat, Western diet. When the animals were exposed to a cold environment (around 4°C), the researchers observed that the animals’ insulin sensitivity and glucose metabolism improved and their body weight decreased, compared to control animals maintained at a thermoneutral zone – the environmental temperature where the body does not need to produce heat for maintaining its core body temperature. What’s more, the scientists also noticed a profound improvement in inflammation, as measured by reduced levels of a major inflammatory marker. 

“We found that brown fat produces Maresin 2, which resolves inflammation systemically and in the liver,” said co-corresponding author Matthew Spite, PhD, a lead investigator at Brigham and Women’s Hospital and Associate Professor of Anesthesia at Harvard Medical School. “These findings suggest a previously unrecognized function of brown adipose tissue in promoting the resolution of inflammation in obesity via the production of this important lipid mediator.”

Moreover, these findings also suggest that Maresin 2 could have clinical applications as a therapy for patients with obesity, metabolic disease, or other diseases linked to chronic inflammation; however, the molecule itself breaks down quickly in the body. Tseng and colleagues seek a more stable chemical analog for clinical use.

The team notes a shortcut to improved metabolic health may already exist. Multiple human studies show that exposure to mild cold temperatures (10 to 13°C) have been shown to be sufficient to activate brown adipose tissue and improve metabolism, though the mechanisms are not well understood.

Source: EurekaAlert

Categories : Regenerative MedicineTags :

Intermittent Fasting May Aid Nerve Repair

On By ModernMedia
A healthy neuron.
A healthy neuron. Credit: NIH

A new mouse study published in Nature showed that intermittent fasting changes gut bacteria, and increases the ability to recover from nerve damage. The fasting led to gut bacteria increasing production of 3-Indolepropionic acid (IPA), a metabolite which is required for regenerating axons.

The bacteria that produces IPA, Clostridium sporogenesis, is found naturally in the guts of humans as well as mice and IPA is found in human bloodstreams too, the researchers said. 

“There is currently no treatment for people with nerve damage beyond surgical reconstruction, which is only effective in a small percentage of cases, prompting us to investigate whether changes in lifestyle could aid recovery,” said study author Professor Simone Di Giovanni at Imperial College London.

“Intermittent fasting has previously been linked by other studies to wound repair and the growth of new neurons – but our study is the first to explain exactly how fasting might help heal nerves.”

The study assessed nerve regeneration of mice where the sciatic nerve, the longest nerve running from the spine down the leg, was crushed. Half of the mice underwent intermittent fasting (one day with food, one day without), while the other half ate freely. These diets continued for a period of 10 days or 30 days before their operation, and the mice’s recovery was monitored 24 to 72 hours after the nerve was severed. The regrown axons were about 50% greater in mice that had been fasting.

Prof Di Giovanni said, “I think the power of this is that opens up a whole new field where we have to wonder: is this the tip of an iceberg? Are there going to be other bacteria or bacteria metabolites that can promote repair?”

The researchers also studied how fasting led to this nerve regeneration. They found that there were significantly higher levels of specific metabolites, including IPA, in the blood of diet-restricted mice.

To confirm whether IPA led to nerve repair, the mice were treated with antibiotics to remove gut bacteria. They were then given gene-edited of Clostridium sporogenesis that could or could not produce IPA.

“When IPA cannot be produced by these bacteria and it was almost absent in the serum, regeneration was impaired. This suggests that the IPA generated by these bacteria has an ability to heal and regenerate damaged nerves,” Prof Di Giovanni said. 

Importantly, when IPA was administered to the mice orally after a sciatic nerve injury, regeneration and increased recovery was observed between two and three weeks after injury.

The next step is investigating spinal cord injuries in mice, along with seeing if more frequent IPA administrations increase its efficacy.

“One of our goals now is to systematically investigate the role of bacteria metabolite therapy.” Prof Di Giovanni said.

More studies will need to investigate whether IPA increases after fasting in humans and the efficacy of IPA and intermittent fasting as a potential treatment in people.

He said: “One of the questions that we haven’t explored fully is that, since IPA lasts in blood for four to six hours in high concentration, would administering it repeatedly throughout the day or adding it to a normal diet help maximise its therapeutic effects?”

Source: Imperial College

Categories : Ethics and Law Obstetrics & GynaecologyTags :

How Will Roe v Wade Decision Influence the World?

On By ModernMedia
Photo by Andy Feliciotti on Unsplash

With the US Supreme Court’s overturning the Roe v Wade decision, abortion rights are now up to individual US states. However, while there are no legal implications for the rest of the world, it will undoubtedly have a huge influence on other countries’ abortion campaigning and lawmaking decisions. Future anti-abortion efforts in the US may also impact the country’s funding of reproductive services in regions such as Africa.

Without access to legal, safe abortion, many pregnant people will turn to unsafe methods. According to the World Health Organization, 97% of all unsafe abortions happen in developing countries. Some 4.7–13.2% of maternal deaths are attributable to unsafe abortion.

Although Roe v Wade does not have a legal effect in Africa, it was frequently invoked in abortion. Tunisia liberalised its abortion law just nine months after the Roe v Wade ruling – allowing women to access the service on demand. Additionally, in 1986, Cape Verde allowed for abortion on request prior to 12 weeks gestation which aligns with Roe v Wade holding of the same.

In South Africa, the right to abortion is not directly enshrined in the Constitution, but the 1996 Choice in Termination of Pregnancy Act greatly widened accessibility to safe, legal abortions, causing a 90% drop in abortion mortality from 1994 to 2001. The previous apartheid-era laws and their enforcement were predictably stained by racism: abortion was limited to encourage white population growth while contraceptives were promoted to control the population growth of black and coloured people. Wealthy whites could fly to England for an abortion there if they could not arrange one. The 1996 Act was met with significant opposition on religious grounds, and it is speculated that had the ANC done this with an open vote, it would not have passed with such a wide margin.

Even today, research shows that abortion remains highly stigmatised among South Africans, with 75.4% of people surveyed indicating that it was “always wrong” in case of family poverty, and 52.5% indicating the same for either foetal abnormality or family poverty. Provincial splits are apparent, with Gauteng and Limpopo having a > 1 odds ratio of being against abortion.

The 2003 Maputo Protocol adopted by the African Union requires countries to authorise medical abortions in cases of sexual assault, rape, incest, or where the health of the mother is endangered. This specific provision draws from the 1979 United Nations Convention on the Elimination of All Forms of Discrimination Against Women (CEDAW), whose clause on access to safe abortion was based on on Roe v Wade. However, 12 AU members have not ratified the protocol, and many of those who did have not fully brought their laws into line. South Africa is only one of six African nations that effectively allow elective abortions. Of these, Mozambique and Benin only fully changed their laws in 2020 and 2021.

Abortion opponents led by the Catholic Church and its affiliates enjoy widespread political and social support in many African countries. In 2020, Bhekisisa investigated African pregnancy crisis centres funded by US anti-abortion groups. These centres actively discourage abortion, exerting pressure on girls and women and are rife with misinformation, such as grossly exaggerating the size and development of the foetus in early stages of pregnancy. One NGO offered training to say that abortion would “turn” women’s partners gay if they got an abortion.

Thus, while the legal outcome of Roe v Wade being overturned will have no bearing on South Africa, it will conceivably embolden anti-abortion groups both domestically and abroad and likely to increase the influence they already exert in the country.