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Research Roundup: Brain circuits for dominance, new HepC rodent model, eye repair in zebrafish and more

Welcome to this week’s Research Roundup. These Friday posts aim to inform our readers about the many stories that relate to animal research each week. Do you have an animal research story we should include in next week’s Research Roundup? You can send it to us via our Facebook page or through the contact form on the website.

  • Brain circuits for social dominance discovered. For humans and most other animals, a previous history of winning dictates continued social dominance. In a study recently published in Science, Zhou et al. may have found a neurological explanation for this “winner effect”. They show, using mice, that the dorsomedial prefrontal cortex (dmPFC) mediates behavior in a social conflict. Using optogenetic methods, researchers stimulated the dmPFC using light and found that this was sufficient to induce “winning” in mice tested on a task used to measure social dominance. Interestingly, this also worked in mice that were previously shown to be a “loser” when paired with another mouse in the task. If an analogous mechanism present in humans, this study could be of major importance in understanding various relevant psychiatric conditions associated with social behavior. This research was published in the journal Science.

  • New animal models for hepatitis C could pave the way for a vaccine. This discovery is a stepping stone towards the development of a vaccine for Hepatitis C which affects nearly 71 million people worldwide. Although there is now a cure for Hepatitis C, most people go undiagnosed leading to damage of the liver. Until now, an animal model was not available for vaccine development because hepatitis C is highly specific affecting only humans and chimpanzees. This breakthrough comes as a result of a collaborative effort with Ian Lipkin, a researcher at Columbia University, who was studying pathogens of common rats in New York City. He found a rat version of the hepatitis virus and after sharing his work with Dr. Charlie Rice, a researcher in virology at The Rockefeller University, they found a way to infect mice with the rat version of the virus. There are differences between the primate and rodent version of the virus but there is hope that “this research will help unravel mechanisms of liver infection, virus clearance, and disease mechanisms, which should prove valuable as we work to develop and test hepatitis C vaccines that can help to finally eradicate the disease around the world.” This study was published in Science.
  • A study in zebrafish found that the immune system controlled its ability to regenerate eye tissue. Researchers at John Hopkins are studying the ability of zebrafish to repair damaged eye retinal tissue using the regenerative response of Müller glia Having found that microglia, a type of cell involved in immune response, were the only cells able to penetrate the blood-retinal barrier, they prevented these cells from functioning, resulting in almost no regeneration from the Müller glia cells. A better understanding of this process could help scientists unlock human eye regeneration. Dr Jeffrey Mumm noted, “humans still have the genetic machinery needed to regenerate retinal tissue, if we can activate and control it.” This study was published in PNAS.
  • Early disruption of gut microbiota shapes later health. The gut microbiome plays an important role for health in humans and all living animals. In a recent study published in Nature Communications, researchers discovered that disruption of gut bacteria in frogs during the tadpole stage of maturation had negative effects on how adult frogs dealt with parasites. This effect may also be present in humans. Wherein, early-life disruption of human microbiota may stimulate the development of an under-reactive immune response to infections in adulthood.

  • Potential treatment for infants exposed to alcohol in utero identified. In the United States 1-5 percent of children are diagnosed with fetal alcohol spectrum disorder, which impairs learning, is linked to later-life behavioral problems, cardiovascular problems, and delayed development. In efforts to reverse these negative effects, scientists at Northwestern University treated rat pups, exposed to alcohol in utero, thyroxin or metaformin. Thyroxin is a hormone that is reduced in pregnant women that consume alcohol, and also in infants with fetal alcohol spectrum disorder. Metaformin is an insulin sensitizing drug that is found at higher concentrations in alcoholics. Both drugs reversed memory deficits, independently, as a consequence of in utero alcohol exposure. “We’ve shown you can interfere after the damage from alcohol is done. That’s huge,” said lead investigator and senior author Eva Redei. “We have identified a potential treatment for alcohol spectrum disorder. Currently, there is none.”The researchers are now looking for funding for clinical trials. This study was published in Molecular Psychiatry.

NIH Director reaffirms importance of animal experiments

Francis Collins, Director of the NIH, was interviewed by the Washington Examiner earlier this week. One question asked what he thought about animal research, to which Collins provided a thoughtful and considered answer.

Washington Examiner: PETA came out this year supporting budget cuts to the NIH, saying that cutting testing on animals would achieve significant savings. What can you tell us about where animal testing stands?

Collins: I think NIH is very focused on making sure that animal studies are done in the most ethical way possible, but also very convinced there are things we can learn from animal studies that will help people with terrible diseases that we otherwise can’t quite learn. We are certainly moving a lot of the kind of research that we used to do in animals into other systems, particularly with human cells that can be grown in a laboratory in a fashion that causes no pain to anybody and doesn’t result in such a great need for animals. But animals are still crucial to our understanding of how biology works. Anybody who has looked at the kind of oversight that applies to that I think will be impressed by how much attention goes toward any protocol that we fund that is going to involve animals for research. It has to have veterinarians and members of the public looking constantly at the conditions under which the animals are cared for and how we do everything possible to avoid the creation of unnecessary pain.

No doubt Collins is tired of PETA’s nonsense – in 2015 they wrote letters to all his neighbors in an effort to pressure him to stop the work of an individual researcher. We applaud Collins for defending animal research to the Washington Examiner and hope he continues to protect vital research in the future.

Animal experiments in the UK decline by 5% in 2016

The UK Home Office has published the 2016 annual statistics showing the number of animal procedures carried out in Great Britain under the Animals (Scientific Procedures) Act, 1986; this covers all vertebrate species (and Cephalopods). In 2016 there were 3.94 million procedures carried out, down 5% from 2015 (4.14 million).

While we often describe these statistics as being for the UK, they do not include Northern Ireland (who carried out 22,508 procedures in 2015), and so are technically the figures for Great Britain (England, Scotland and Wales).

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Procedures on animals in Great Britain for research in 2016. Click to Enlarge

Overall, 96.6% of animals used in scientific studies were mice, rats, fish or birds. Dogs, cats and primates (which are offered special protections under UK law) together accounted for 0.22% of the total (similar to in previous years). The statistics also reveal that almost half of all experiments (48.6%) were the breeding of GM animals which were not used in further experiments – this is almost identical to 2014 and 2015. Overall, 64.9% (almost two thirds) of all experiments involved genetically modified animals, this was down from 67% in 2015.

Different colours represent changes to the counting method in 1987 and 2014.

Trend over time in animal experiments in the UK. Click to Enlarge.

Using the trend graph we can see how the number of animals used in research appears to be flattening out after almost two decades of rising numbers. It should be noted that the Home Office reported in 2015 that it believes there were statistical errors in the 2014 report as a result of new counting methodologies, but that this has been ironed out for 2015 and 2016.

The last five years appears to show animal experiments remaining relatively constant around 4 million. While this is higher than in the 1990s, it remains much lower than the 5.5+ million animals used in the mid 1960s.

Procedures on non-human primates fell slightly from 3,612 procedures in 2015, to 3,569 (down 1%) in 2016. The number of procedures on cats fell by 19 to 190 procedures and on dogs rose to 4,932.

A ban on cosmetic testing on animals (1998) and of using great apes (gorillas, orang-utans and chimpanzees) in research (1986) meant both had zero procedures in 2015. It should be noted that some research may continue on great apes in zoos, however such research can be observation-based only as “procedures” on great apes are illegal under ASPA.

For the third time the UK statistics include retrospective reporting of suffering. Rather than just submitting licence proposals to the Home Office that include estimated levels of suffering, the researchers now have to report on what was actually seen (using a variety of measures). Unfortunately, the statistics put these in two separate tables (Table 3 and 8). So we have combined them to get severity for all procedures in 2016. We can see most experiments are sub threshold (38%; less than the introduction of a hypodermic needle), non-recovery (4%; the animal never awakes from anaesthesia) or mild (38%), with remainder as moderate (16%), or severe (3.9%) Overall the proportion of moderate and severe rose from 18.2% in 2015 to 19.9% in 2015 (though numbers in severe category fell). Also of note in the severity data is the rising proportion of sub-threshold experiments in the creation/breeding of genetically modified animals from 45% in 2014, to 55% in 2015, to 65% in 2016, suggesting improving methods.

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Severity of animal research in the UK in 2016

Other things to note in the UK statistics:

  • 48.6% of procedures were for the creation and breeding of genetically altered animals (not used in other experiments), 28.5% were for basic research, 13.5% was for regulatory purposes and 8.6% was translational/applied research [Table 1]
  • Over the experimental procedures, 64% of the “severe” experimental procedures were conducted on mice for regulatory purposes. This is often because death is an endpoint in such procedures [Table 3.1]
  • Over 97% of the animals were born in the UK [Table 2.1]
  • 49.2% of procedures were conducted in universities and medical schools, 25.3% were in commercial organisations (e.g. pharmaceuticals), 13.2% were done at non-profit making organisations (e.g. medical research charities), and 12.2% were done at other public bodies. [Table 11]

Speaking of Research congratulate the UK government on continuing to produce the most comprehensive statistics on animal experiments worldwide. It is also important to note that these statistics are released as a press conference each year where representatives from the scientific community speak about the importance of animals in research.

For animal research statistics of countries around the world please see our statistics page.

Source of UK Statistics: https://www.gov.uk/government/statistics/statistics-of-scientific-procedures-on-living-animals-great-britain-2016

See previous years’ reports:

Speaking of Research

EU Regulations on animal research explained

The Speaking of Research website aims is one of the biggest and most accurate resources for information about animal research worldwide. In our mission to provide as much information as possible, we have recently added a page on the European Union’s regulation of animal experiments. While regulations across the 28-EU countries are created and implemented at a national level, they must all conform to EU Directive 2010/63, which aims to harmonise the regulations between member countries. 

Our new page on “Animal Research Regulation in the EU“, adds to those pages on UK and US legislation, to help people understand the requirements that EU Directive 2010/63 places on EU member countries.

See an overview of EU legislation below:

Countries in Europe have differing systems of regulation, but those within the European Union must meet the standards set out by EU Directive 2010/63/EU. The purpose of the Directive is to harmonise standards across the EU, as well as to promote and implement the 3Rs – Replacement, Refinement and Reduction  of animals used for research. The Directive was adopted in 2010, but member states were given until January 2013 to transpose these regulations into domestic law.

Where specific parts of a country’s laboratory animal welfare standards were higher, they were permitted to retain them, for example, the UK retains its additional protections for cats, dogs, horses and primates. However, overall, the minimum regulations set by the EU are high by international standards. Every aspect from cage sizes to staff training is covered, with the 3Rs of Reduction, Replacement and Refinement at the heart of the Directive’s aims. The Directive requires a risk-based inspection regime and lays down minimum standards for housing and care, and systematic project evaluation. While the UK follows these EU regulations, we have written about their specific rules and regulations on our Animal Research Regulations in the UK page. In March 2017, the UK gave notice of its intention to leave the EU, however, the Government has so far suggested it intends to maintain its current animal welfare legislation after Brexit.

The legislation covers non-human vertebrate species (including independently feeding larval forms and last trimester foetal forms of mammals) and cephalopods.

Cephalopods, such as octopus and cuttlefish, are protected under EU regulations

[…]

All EU countries must also provide public statistics outlining the numbers of animal procedures completed each year. These are broken down in many ways, including by species, by type of research, and by severity. Speaking of Research provide analysis of these national statistical releases, which can be found on our Animal Research Statistics page. Across the EU, mice, rats, birds and fish tend to account for over 90% of the animals used in each country.

Scientists must also produce a non-technical summary of their experiment – essentially an abstract stripped of esoteric language so it can be understood by a layman. In countries such as the UK, these are made available on the regulator’s website for the general public to see (UK example).

To read the whole article, see our page on EU legislation.

Speaking of Research

Research Roundup: Artificial bile ducts, saving bat populations, safety of CRISPR and more

Welcome to this week’s Research Roundup. These Friday posts aim to inform our readers about the many stories that relate to animal research each week. Do you have an animal research story we should include in next week’s Research Roundup? You can send it to us via our Facebook page or through the contact form on the website.

  • CRISPR gene editing technique argued to be probably safe. In a previous research roundup, we highlighted the ongoing debate with respect to the safety of the CRISPR-Cas 9 gene editing technique. In that study, it was argued that despite using this technology to restore sight to mice, when looking at the whole genome of the animals, hundreds of areas other than that targeted DNA sections were affected in three of those mice. In a new preprint of an article (non-peer reviewed), researchers argue that the differences that were found were simply a consequence of genetic relatedness rather than unexpected mutations. While it is still far from certain which side is correct, such dialogue and debate highlight the stringency that most treatments that eventually make it humans go through before introduction to the general population — much in part because of animal research.

  • Artificial bile ducts successfully grown in the lab and transplanted into mice could help treat liver disease in children. Scientists in Cambridge, UK, have developed a new method for growing artificial bile ducts in the lab and successfully transplanting them into lab mice — a development that could one day be used to treat liver disease in children. The discovery could also reduce the need for liver transplants in these patients. The researchers extracted healthy cells (called cholangiocytes) from bile ducts and grew them into functioning 3D structures known as biliary organoids. Researchers then grew the organoids on a “biodegradable collagen scaffold” in order to shape the organoid into a tube, which they then transplanted into mice to replace damaged bile ducts. The transplants were successful, and the animals survived without any further complications. The scientists emphasized the “power of tissue engineering and regenerative medicine that these results demonstrate. “These artificial bile ducts will not only be useful for transplanting, but could also be used to model other diseases of the bile duct and potentially develop new drug treatments,” said Dr. Fotrio Sampaziotis, lead author on the study.
    The research was published in Nature Medicine.
  • Antibodies of mother halt placental transmission of cytomegalovirus in monkeys. In our research roundup two weeks ago, we highlighted the debilitating effects of CMV on infants. Approximately 50% of all humans over the age of 40 harbour the CMV, and over 1 million infants a year are infected worldwide. Here, for the first time, researchers studied whether the offspring of mothers exposed to CMV specific antibodies, would confer protection to their offspring from the virus in utero. In the first experiment they found that dosing with CMV antibodies prevented abortion of the fetus and in a second experiment found that a higher dose completely blocked transmission of the virus.While the virus in rhesus macaques is not identical to that in humans (RhCMV) much can be learned from studying this derivative of the disease in non-human animals – similar to the study of SIDS in our understanding of AIDS. In terms of the applicability of this work, lead author, Cody Nelson, a PhD student at DUke university says “Ending congenital CMV infection is likely going to require an effective vaccine given before pregnancy, similar to how the rubella vaccine has eradicated congenital rubella syndrome in the Americas.” This research was published in the journal JCI Insights.
  • Thermal imagery of bat hibernation suggests group behavior for combating white-nose syndrome. Insect-eating bats play a large role in pest control services, likely saving the U.S. agriculture industry upwards of $3 billion a year. However, white-nose syndrome is a fungal disease that has been spreading rapidly across North America for the past decade and is causing steep declines in bat populations. A recent study by researchers at Massey University in New Zealand, used temperature-sensing cameras on hibernating bats with white-nose syndrome to better understand how some bats survive white-nose syndrome during hibernation, while others do not. Interestingly, they found that a species of bat (Indiana bats, Myotis sodalis) — that is less affected by the disease than others (little brown bats, M. lucifugus)– slowly warmed up as a synchronous group, which may have enabled body temperatures to be less conducive to fungal growth and increase the bat’s ability to survive the disease. Not only does this basic research help us  towards finding solutions to mitigate the declining bat population, but it also may help scientists in the future to combat disease in astronauts who will hibernate during long-term space travel.

A northern long-eared bat was affected by white-nose syndrome in Illinois. Credit: J.R. Hoyt.

  • Cilene Lino de Oliveira has won the Basel Declaration Society 2017 Award for Education in Animal Research. Oliveira, from the Department of Physiological Sciences at the University of Santa Catarina, teaches the University’s “Laboratory Animal Care and Welfare” course. The award will give her the opportunity to do an EU course in animal welfare at the Institute for Laboratory Animal Science at the University of Zurich.

Switzerland’s animal research in numbers for 2016

The statistics for animal research conducted in Switzerland in 2016 were released today. We have translated these tables to English and these data are summarized below. Overall, there were 629,773 animals used in research and animal testing in Switzerland in 2016 — a 7.7% decrease compared to the previous year.

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Animal research in Switzerland for 2016 by species [Click to Enlarge]

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Animal research in Switzerland by species and use.
* We have added a column titled Total 2015 to aid with the ease of comparison to the previous year.

According to the Federal Veterinary Office, the BLV, this decrease is “mainly due to the completion of various projects with a large number of fish and amphibians”. Most of these animals were involved in basic research (64.4%), with “discovery, development and quality control” being the next most common (19.4%). The remainder were used for other reasons including disease diagnosis, education and training and protecting the environment. Mice were again the most prevalently used species (65.19%).

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97.1% of the animals used in research and testing was conducted on mice, rats, fish, and birds, similar to other European countries. Monkeys (198), cats (411) and dogs (616) together accounted for 0.2% of all research animals, with an overall decrease of 2553 animals from 2015 for these species.

Severity in Switzerland works in the follow way (Translated definitions of the severity grading procedure for animals used in experiments in Switzerland):

The following four categories are used for constraints on animals resulting from procedures or measures in the context of animal experiments:

  • Severity grade 0: no constraint: Procedures and actions performed on animals for experimental purposes that do not inflict pain, sufffering or harm on the animals, engendr fear or impair their general well-being;
  • Severity grade 1: mild constraint: Procedures and actions performed on animals for experimental purposes that cause short-term mild pain or harm or mild impairment of general well-being;
  • Severity grade 2: moderate constraint: Procedures and actions performed on animals for experimental purposes that cause short-term moderate or medium-long term mild pain, suffering or harm, short term moderate fear or short to medium-term severe impairment of general well-being;
  • Severity grade 3: severeconstraint: Procedures and actions performed on animals for experimental purposes that cause medium to long-term moderate pain or severe pain, medium to long term moderate harm or severe harm, long-term severe fear or a severe impairement of general well-being

Pain, suffering and harm, were also measured and classified under four grades of severity; 0, 1, 2 and 3. In 2016, 38% of experiments were Grade 0, 31% were Grade 1, 21% were Grade 2 and 2% were Grade 3.

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Severity of animal experiments by species, 2016

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Severity grade data are only available from 1997 onwards

These numbers are relatively consistent across time, with on average 78% of all animals being exposed to no or minor short-lasting pain and distress.

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Overall there has been a steady downward trend in the number of animals used in research in Switzerland over the last 30 years.

See details of Switzerland’s 2015 statistics.

 

Jeremy D. Bailoo

Research with dogs develops an artificial pancreas to treat diabetes

White Coat Waste is a conservative animal rights organization devoted to the elimination of animal research. Its first target is biomedical research conducted using dogs at the US Department of Veterans Affairs (VA). Unfortunately, this campaign is gaining traction. While White Coat Waste is supported mainly by Republicans, some Democrat representatives like Dina Titus (Nevada) and Ted Lieu (California) have expressed their support. In view of that, it is important to highlight the remarkable achievements of dog research at the VA and the tremendous loss that its cancellation would be for Veterans and the general public. 

Diabetes is a nasty disease that affects millions of people worldwide and continues to increase. It is a metabolic disorder in which the body becomes incapable of controlling the blood levels of glucose, either because the pancreas fails to produce enough insulin (type 1) or because cells in the body fail to respond to insulin (type 2). Untreated, diabetes can lead to cardiovascular disease, stroke, kidney disease, neuropathic pain, gangrene of the extremities, amputations, blindness, and death. In 2014, 422 million people had diabetes worldwide (8.5% of the population). These numbers have more than tripled since 1980 (108 million; 4.7% of the population) and continue to increase due to poor dietary habits and lack of exercise. The annual number of deaths worldwide was estimated at 4.9 million in 2014. The incidence of diabetes is particularly high in the USA and other developed countries, but it is increasing fast in Asia and Africa. In the USA, diabetes has a high impact in Veterans: one in four patients receiving care at the US Department of Veterans Affairs (VA) has diabetes. This makes it a high priority for medical research at the VA.

People with serious cases of diabetes need multiple daily injections of insulin. Failure to administer the insulin appropriately can lead to kidney failure, amputations, blindness, coma, and even death. However, the dose of insulin has to be tuned to the needs of the body. To do this, patients measure the glucose level in their blood by drawing blood from their fingers using needle sticks. This has to be done several times a day in order to calculate and inject insulin according to the blood glucose levels. An artificial pancreas has been developed at the VA to help improve the outcomes for diabetic patients. This device measures glucose in the blood in real time and automatically administers the right dose of insulin. This technology will dramatically improve the patient’s quality of life and reduce life-threatening complications. It would also tremendously reduce diabetes-related healthcare costs.

The artificial pancreas uses a reconfigured smart phone as part of its system. Image by UVA

This research project was initiated decades ago by Dr. Seymour Levin, a VA endocrinologist who specialized in diabetes and was horrified by the large number of VA patients who needed amputations because of problems with properly administering insulin to treat their diabetes. He obtained funds from the Mann Foundation. In the early 1980s, the Mann Foundation created a company called MiniMed Technologies to design an insulin pump that patients could wear throughout the day. MiniMed Technologies used dogs at the VA diabetes laboratory to test prototypes of this pump. In the early 2000s the company was acquired by Medtronic, which has been fully supporting this research project ever since. No taxpayer money has been used for it, a detail that seems to be important for White Coat Waste.

Taking advantage of new computer technology, the device being developed incorporates not only an insulin pump but also a glucose sensor and software to calculate the amount of insulin to be injected into the blood according to the glucose level. This makes it a true artificial pancreas. Working with dogs allows researchers to do the pre-clinical testing of the artificial pancreas required for approval by the USA Food and Drug Administration (FDA) at the same time that the hardware and the software are refined and improved.

Why use dogs for this research project? Animals like mice, rats or guinea pigs are too small for the devices being tested and their blood volume is not large enough to allow for frequent blood sampling without causing them harm. On the other hand, dogs have been an important model for metabolic studies and can replicate human diabetes quite well (much early research into diabetes and insulin relied on research in dogs). They can also be used for long-term studies lasting years, which are not possible in rodents. The sensors and catheters implanted in the dogs are the same ones to be used in humans, and the dogs adapt very well to wearing them. Dogs also like interacting with humans and can be trained to go along with these painless procedures without needing to be anesthetized or restrained. Other large animals like pigs and sheep were tried and were found to be far less suitable than dogs for this work.

The standard procedure consists of having the dog rest on a soft bed, unrestrained. Glucose sensors are inserted under the skin and an insulin pump is attached via a subcutaneous catheter (similar to a human patient using these devices). The procedures are painless and the dog soon becomes habituated to them. The dog is given a small amount of glucose solution to raise its blood-glucose level in order to see how the experimental sensor, software, and pump respond. Blood samples are then tested on a large and expensive glucose analyzer to see how well the sensor is working.

The dogs in the VA diabetes research project are very well cared for, and the diabetic ones are maintained on insulin pumps. Pet dogs sometimes develop diabetes as they age. Just like humans, they develop cataracts, kidney problems and all the other complications of diabetes. Even when they are given insulin injections under a veterinarian’s care, they all die within 1-2 years. In contrast, the diabetic dogs in this research program are maintained free of symptoms by the insulin pumps and live at least a decade with no cataracts or other diabetes complications. Non-diabetic dogs are adopted out at the end of the study period whenever feasible.

dog, animal testing, animal experiment

Beagle in research

On September 28, 2016, the FDA approved the first artificial pancreas, the Medtronic’s MiniMed 670G System, intended to automatically monitor blood-glucose levels and adjust basal insulin doses in people with type 1 diabetes. The pre-clinical testing of this device was all done on dogs at the VA diabetes research laboratory. However, the research project is ongoing and much work remains to be done. If it is canceled due to political pressure from White Coat Waste, it would be a huge loss for Veterans and the millions of people worldwide who need more reliable ways to treat their diabetes.

Juan Carlos Marvizon, Ph.D.

References:

  1. Grosman B, Voskanyan G, Loutseiko M, Roy A, Mehta A, Kurtz N, Parikh N, Kaufman FR, Mastrototaro JJ, Keenan B. Model-based sensor-augmented pump therapy. J Diabetes Sci Technol. 2013 Mar 1;7(2):465-77.
  2. Loutseiko M, Voskanyan G, Keenan DB, Steil GM. Closed-loop insulin delivery utilizing pole placement to compensate for delays in subcutaneous insulin delivery. J Diabetes Sci Technol. 2011 Nov 1;5(6):1342-51.
  3. Panteleon AE, Loutseiko M, Steil GM, Rebrin K. Evaluation of the effect of gain on the meal response of an automated closed-loop insulin delivery system. Diabetes. 2006 Jul;55(7):1995-2000.