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Kashmir Times. Dated: 11/6/2022 11:38:34 PM

FRAILTY, DEMENTIA BOOST OLDER ADULTS' DEATH RISK AFTER SURGERY
New research finds striking differences in the mortality rate of older Americans within a year of having major surgery.
These differences were particularly pronounced for geriatric-specific conditions such as frailty or dementia.
The findings have major implications for the way US health care providers and policymakers think about major surgery in certain subgroups of older persons and how providers manage pre-operative and post-operative care for people who are age 65 and older.
"Our findings define the scope and scale of mortality after major geriatric surgery in the US," says Thomas M. Gill, professor of geriatric medicine at Yale University and lead author of the study, published in JAMA Surgery. "They suggest a mixed landscape of surgical quality and safety among older persons."
Overall, according to the study, nearly 1 in 7 older Americans not living in a nursing home died in the year after major surgery, including more than 1 in 4 who were frail and nearly 1 in 3 who had probable dementia.
By comparison, the expected 1-year mortality rate for the study population was less than 1 in 20 had they not undergone major surgery.
"These numbers highlight the prognostic importance of geriatric conditions such as frailty and dementia, two key determinants of health and well-being in older persons," Gill says.
The findings also point to the critical need to take such conditions into consideration prior to major surgery, the researchers say.
"With improved preoperative optimization and recognition as well as enhanced perioperative management strategies, it is possible that mortality after major surgery could be reduced among older persons, especially those in high-risk subgroups," says senior author Robert D. Becher, assistant professor of surgery.
For the study, researchers looked at 1,193 major surgeries identified from 992 fee-for-service Medicare beneficiaries, from the National Health and Aging Trends Study (NHATS), from 2011 to 2018. Information on frailty and dementia came via annual NHATS assessments. Information about surgeries and mortality came via data from the Centers for Medicare & Medicaid Services.
The study was conducted at the Yale Claude D. Pepper Older Americans Independence Center. The National Institutes of Health and the National Institute on Minority Health and Health Disparities funded the work.
WHIPPED CREAM MADE FROM
BACTERIA COULD BE THE FUTURE
Bacteria-based whipped cream could be the future, researchers say.
Food researchers have developed a fat-free prototype of the much-beloved substance using bacteria instead of milk fat-in both velvety and stiffer varieties.
The concept opens up the possibility of producing alternative whipped creams using beer brewing residues and plants, which increases sustainability.
Whipped cream is composed of 38% saturated fat, making it a not so fluffy caloric and climate issue as well. Therefore, the researchers set out to develop a low-fat, more sustainable alternative.
A delicious whipped cream needs to be versatile. For a tart, it needs to be velvety, smooth, light, and airy. And at other times, it needs to be stiff enough to hold the shape of a cake for hours. The thing most special about whipped cream is its consistency.
"The most difficult aspect of developing an alternative food is getting the texture right. Whipped cream undergoes a unique transformation that occurs in a complex system where a high saturated fat content makes it possible to whip the cream stiff," explains Jens Risbo, an associate professor of the food science department at the University of Copenhagen.
"So, how do we create an alternative where we avoid the high fat content, while still achieving the right consistency? This is where we need to think innovatively."
For a number of years, Risbo and a group of researchers have been working on using lactic acid bacteria as tiny building blocks for creating food. They have now succeeded in illustrating their knowledge by creating a whipped cream in both fluffy and stiff versions.
"We usually associate bacteria with something to keep away from food. But here, we base a beloved food product on good bacteria found in nature. This has never been seen before. This is advantageous, both because it is a renewable resource grown in a tank, and because it creates a healthier, less energy dense, fat-free product," says Risbo, who is the lead author of the study in Food Hydrocolloids.
Lactic acid bacteria are ubiquitous. Some live on plants, while others are found naturally on human and animal mucous membranes, as well as in their digestive tracts. In the food industry, these bacteria are used to culture yogurt and as a preservative for cold cuts. Here, they are put to work in an entirely new way-to serve as the building blocks of a food product, where they play the leading role.
Dairy-based whipped cream is formed as the fat globules in cream clump up during whipping, until the airy foam stabilizes and provides the strength necessary to stand and not let liquid drain out. This requires a lot of fat globules, which is why heavy whipping cream has a fat content of 38%.
While there are a number of non-dairy artificial whipped creams on the market, they are made from other saturated sources of fat, such as coconut or palm fat, which are imported from the tropics. Furthermore, they contain at least 25% fat. Finally, their production is usually complicated to manage and involves a long list of food additives.
"Here we only use four ingredients-water, bacteria, a bit of milk protein, and a single thickener. With these few ingredients, we've managed to make a fat-free product that can be whipped, peaks up, and retains the liquid," explains Risbo.
The researchers used two different lactic acid bacteria for the two versions of the bacteria-based foam, both of which are roughly the same size as the fat globules in dairy-based whipped cream. The differing surface properties of each bacteria provide the foams with different structures. One bacterial species, whose surface likes water, forms a weak network that produces a softer foam. The second bacterial species, which is more similar to fat, forms stronger networks and thus a stiffer foam that can stand in taller, pretty peaks.
Risbo points out that the bacteria-based foam is a proof-of-concept, which should not be seen as a stand-alone product, but considered as new knowledge that provides insight into how to create a similar food structure using non-dairy sources.

"We've shown that bacteria can be used to create the right structure. Now that we understand the context and have learned which surface properties are important, it opens up the possibility of using many other things from nature. This could be yeast residue from brewing, or perhaps small building blocks that we extract from plants. This would make the product very sustainable," concludes Risbo.
Additional researchers from the University of Copenhagen and Manchester Metropolitan University, UK, contributed to the work.
Support for the research came from the Danish Council for Independent Research.