Specific receptors in the ears of mosquitoes have been revealed to modulate their hearing, finds a new study led by researchers at UCL and University of Oldenburg. Since male mosquitoes need to hear female mosquitoes is a crucial factor in their reproduction, this discovery could help develop new insecticides and control the spread of harmful diseases, such as malaria, dengue, and yellow fever.
In the study, published in Nature Communications, the researchers focused on a signalling pathway involving a molecule called octopamine. They demonstrated that it is key for mosquito hearing and mating partner detection, and so is a potential new target for mosquito control.
Male mosquitoes acoustically detect the buzz generated by females within large swarms that form transiently at dusk.
As swarms are potentially noisy, mosquitoes have developed highly sophisticated ears to detect the faint flight tone of females amid hundreds of mosquitoes flying together.
However, the molecular mechanisms by which mosquito males ‘sharpen their ears’ to respond to female flight tones during swarm time have been largely unknown.
The researchers looked at the expression of genes in the mosquito ear and found that an octopamine receptor specifically peaks in the male mosquito ear when mosquitoes swarm.
The study found that octopamine affects mosquito hearing on multiple levels. It modulates the frequency tuning and stiffness of the sound receiver in the male ear, and also controls other mechanical changes to boost the detection of the female.
The researchers demonstrated that the octopaminergic system in the mosquito ear can be targeted by insecticides. Mosquito mating is a bottleneck for mosquito survival, so identifying new targets to disrupt it is key to controlling disease-transmitting mosquito populations.
Clinicians are all too familiar with the ‘Google patient’ who finds every scary, worst-case or outright false diagnosis online on whatever is ailing them. During COVID, misinformation spread like wildfire, eroding the public’s trust in vaccines and the healthcare profession. But now, AI models like ChatGPT can be whispering misleading information to the clinical researchers trying to produce real research.
Researchers from CHU Sainte-Justine and the Montreal Children’s Hospital recently posed 20 medical questions to ChatGPT. The chatbot provided answers of limited quality, including factual errors and fabricated references, show the results of the study published in Mayo Clinic Proceedings: Digital Health.
“These results are alarming, given that trust is a pillar of scientific communication. ChatGPT users should pay particular attention to the references provided before integrating them into medical manuscripts,” says Dr Jocelyn Gravel, lead author of the study and emergency physician at CHU Sainte-Justine.
Questionable quality, fabricated references
The researchers drew their questions from existing studies and asked ChatGPT to support its answers with references. They then asked the authors of the articles from which the questions were taken to rate the software’s answers on a scale from 0 to 100%.
Out of 20 authors, 17 agreed to review the answers of ChatGPT. They judged them to be of questionable quality (median score of 60%). They also found major (five) and minor (seven) factual errors. For example, the software suggested administering an anti-inflammatory drug by injection, when it should be swallowed. ChatGPT also overestimated the global burden of mortality associated with Shigella infections by a factor of ten.
Of the references provided, 69% were fabricated, yet looked real. Most of the false citations (95%) used the names of authors who had already published articles on a related subject, or came from recognised organisations such as the Food and Drug Administration. The references all bore a title related to the subject of the question and used the names of known journals or websites. Even some of the real references contained errors (eight out of 18).
ChatGPT explains
When asked about the accuracy of the references provided, ChatGPT gave varying answers. In one case, it claimed, “References are available in Pubmed,” and provided a web link. This link referred to other publications unrelated to the question. At another point, the software replied, “I strive to provide the most accurate and up-to-date information available to me, but errors or inaccuracies can occur.”
Despite even the most ‘truthful’ of these responses, ChatGPT poses hidden risks to academic, the researcher say.
“The importance of proper referencing in science is undeniable. The quality and breadth of the references provided in authentic studies demonstrate that the researchers have performed a complete literature review and are knowledgeable about the topic. This process enables the integration of findings in the context of previous work, a fundamental aspect of medical research advancement. Failing to provide references is one thing but creating fake references would be considered fraudulent for researchers,” says Dr Esli Osmanlliu, emergency physician at the Montreal Children’s Hospital and scientist with the Child Health and Human Development Program at the Research Institute of the McGill University Health Centre.
“Researchers using ChatGPT may be misled by false information because clear, seemingly coherent and stylistically appealing references can conceal poor content quality,” adds Dr Osmanlliu.
This is the first study to assess the quality and accuracy of references provided by ChatGPT, the researchers point out.
The Select Committee on Health and Social Services has extended the deadline for public comments on the contentious National Health Insurance (NHI) Bill by two weeks, according to a report from Business Insider. In its announcement, the Committee said that it had received numerous requests from stakeholders to extend the date on written submissions for the act.
The committee has therefore extended the deadline from Friday, 1 September 2023 to Friday, 15 September 2023. The Bill is already before the National Council of Provinces (NCOP) after being passed by Parliament in June, in spite of vehement opposition. Once past the NCOP, which seems all but assured given its stubborn progress, it will then be sent to President Cyril Ramaphosa to be signed into law.
Contact details to submit enquiries or written submissions are at the end of the article.
Controversy continues unabated
An unrelenting barrage of criticism has been directed at the Bill, which so far has shown little change in response and according to many its constitutionality is questionable. While stakeholders are generally for universal healthcare and the idea of an NHI, the current public healthcare system is already under dire pressure, being underfunded, under-resourced in terms of skilled professionals and equipment, and riddled with corruption.
Indeed, South Africa would be the first country in the world to completely bring all healthcare. The fact that other countries with better governance track records and more resources have not done so has been brought up as a red flag.
Another is the vague notion that the government will pay for the scheme somehow – which inevitably means reaching into taxpayers’ wallets. The estimated cost of R300 billion and R660 billion a year will be by far the largest single government expense in a time of shrinking funds.
“Looking at 2026 – the year in which the NHI is supposed to be implemented – an enormous extra R296 billion will be required in order to balance the books,” the Solidarity Research Institute (SRI) said.
“This is unheard of for a middle-income country, where spending on education usually enjoys the highest priority. While more affluent countries spend more on healthcare, social grants usually receive the highest priority, never health,” said the SRI.
Options to foot the bill range from a staggering 40% surcharge on income tax to a payroll tax of 13.4%, which Professor Alex van den Heever criticised as being “incredibly naïve set of fiscal proposals that you cannot even consider implementing.” Discovery Health CEO Ryan Noach warned of a tax revolt if the government attempts to pay for this.
Practical allternatives on offer include a public-private partnership as envisaged by Business Leadership South Africa CEO Busi Mavuso.
Enquiries, as well as written submissions, can be directed to Ms M Williams, Select Committee on Health and Social Services, e-mail mawilliams@parliament.gov.za.
Surgeons at NYU Langone Health have transplanted a genetically engineered pig kidney that continues to function well after 32 days in a man declared dead by neurologic criteria and maintained with a beating heart on ventilator support. This represents the longest period that a gene-edited pig kidney has functioned in a human, and the latest step toward the advent of an alternate, sustainable supply of organs for transplant.
Led by Robert Montgomery, MD, DPhil, the procedure was performed on July 24, 2023 and marks the fifth xenotransplant performed at NYU Langone. Observation is ongoing and the study will continue through mid-September 2023.
“This work demonstrates a pig kidney – with only one genetic modification and without experimental medications or devices – can replace the function of a human kidney for at least 32 days without being rejected,” said Dr Montgomery, who had previously performed the world’s first genetically modified pig kidney transplant into a human decedent in 2021.
Removing single troublesome gene
The first hurdle to overcome in xenotransplants is preventing so-called hyperacute rejection, which typically occurs just minutes after an animal organ is connected to the human circulatory system. By “knocking out” the gene that encodes the biomolecule known as alpha-gal, responsible for a rapid antibody-mediated rejection of pig organs by humans, immediate rejection has been avoided in all five xenotransplants at NYU Langone. Additionally, the pig’s thymus gland, which is responsible for educating the immune system, was embedded underneath the outer layer of the kidney to stave off novel, delayed immune responses. The combination of modifications has been shown to prevent rejection of the organ while preserving kidney function.
To ensure the body’s kidney function was sustained solely by the pig kidney, both of the transplant recipient’s native kidneys were surgically removed. One pig kidney was then transplanted and started producing urine immediately without any signs of hyperacute rejection. During the observation phase, intensive care clinical staff maintained the decedent on support while the pig kidney’s performance was monitored and sampled with weekly biopsies. Levels of creatinine, a bodily waste product found in the blood and an indicator of kidney function, were in the optimal range during the length of the study, and there was no evidence on biopsy of rejection.
The surgery was the latest in a larger study approved by a specific research ethics oversight board at NYU Langone and was performed after consultation with the New York State Department of Health. This important research, which study leaders say could save many lives in the future, was made possible by the family of a 57-year-old male who elected to donate his body after a brain death declaration and a circumstance in which his organs or tissues were not suitable for transplant.
A big leap toward a new organ source
“There are simply not enough organs available for everyone who needs one,” said Dr Montgomery, who received a hepatitis C-positive heart transplant himself in 2018. “Too many people are dying because of the lack of available organs, and I strongly believe xenotransplantation is a viable way to change that.”
The kidney and thymus gland used in this procedure were procured from a GalSafeTM pig, an animal engineered by Revivicor, Inc., a subsidiary of United Therapeutics Corporation. In December 2020, the U.S. Food and Drug Administration (FDA) approved the GalSafe pig as a potential source for human therapeutics as well as a food source for people with alpha-gal syndrome, a meat allergy caused by a tick bite.
Less may be more
While previous genetically engineered pig organ transplants have incorporated up to 10 genetic modifications, this latest study shows that a single-gene knockout pig kidney can still perform optimally for at least 32 days without rejection.
“We’ve now gathered more evidence to show that, at least in kidneys, just eliminating the gene that triggers a hyperacute rejection may be enough along with clinically approved immunosuppressive drugs to successfully manage the transplant in a human for optimal performance – potentially in the long-term,” said Dr Montgomery.
The NYU Langone team used standard transplant immunosuppression medications combined with enhanced screening of porcine cytomegalovirus (pCMV) in the donor pig to ensure safety. Recent studies have shown pCMV may affect organ performance and potentially trigger organ failure. No pCMV was detected after 32 days, and close surveillance of porcine endogenous retrovirus (PERV), along with six other viruses of interest, was performed.
Next steps
Monitoring of the pig kidney recipient will continue for another month with permission from the family, ethics committee approval and continued support from United Therapeutics. The additional data from the next several weeks will be analyzed further to develop a deeper understanding of this unique medical advance.
“We think using a pig already deemed safe by the FDA in combination with what we have found in our xenotransplantation research so far, gets us closer to the clinical trial phase,” said Dr Montgomery. “We know this has the potential to save thousands of lives, but we want to ensure the utmost safety and care as we move forward.”
