New research published in the Journal of Internal Medicine demonstrates that optogenetics, a technique which uses light-sensitive proteins to control the activity of targeted cells. is a promising shock-free approach to treating atrial fibrillation (AF), or an irregular, often rapid heart rate, for immediate restoration of regular rhythm.
Current treatments for AF, which include medications and shocks to restore a regular heart rhythm, come with low success rates and/or serious side effects. In this new study, rats’ hearts were optogenetically modified to express light-gated ion channels. After AF was induced, the animals’ chests were illuminated resulting in acute restoration of regulation rhythm. This shows that sufficient light penetrated the chest wall, which suggests that full penetration of the human atrial wall may be feasible as well, if deemed necessary for clinical translation.
“Shock-free cardioversion of AF would allow restoration of regular rhythm at any place and time, which may improve the prognosis and quality of life of patients suffering from AF. We hope that our paper will contribute to the realization of this much desired option in clinical practice,” said corresponding author Daniël A. Pijnappels, PhD, of Leiden University Medical Center, in The Netherlands.
A number of service providers have voluntarily ended their contracts with the Gauteng Department of Health to provide food to hospitals. In response, Gauteng Health is looking at a multi-vendor approach to tackle the problem which it blames on vendors being unable to fulfil their orders.
Meanwhile, Gauteng continues to battle with surgical and cancer treatment backlogs. R784 million has been allocated to this end, with a portion allocated to cancer treatment services, some of which will be outsourced to the private sector and some of which is going to new radiotherapy equipment.
This year has seen a number of Gauteng hospitals battling to secure their food supplies. Responding to SA parliamentary questions, Gauteng Health MEC Nomantu Nkomo-Ralehoko wrote that 26 out of 34 Gauteng public hospitals have been affected by food shortages.
“The shortages were mostly due to suppliers not being paid, contracts expiring, or companies not delivering. It was so bad for two hospitals, Bronkhorstspruit and Lenasia South, they had to borrow food from other hospitals!” said DA Shadow MEC for Health, Jack Bloom, who posed the questions.
Hospitals have being going through long stretches of not being able to provide full meals: at George Mukhari Hospital, chicken, fish and frozen vegetables were unavailable for four months, and there was no milk from February to May. The petty cash budgets are woefully insufficient to cover the gap: Kalafong hospital can only spend R2000 a day, not nearly enough to feed its 700 patients, reports SA People.
According to News24, Gauteeng Health spokesperson, Motalatale Modiba, said that the main problem was down to vendors struggling to fulfil their orders on time.
Currently, Gauteng health is running a tender to outsource oncology services for the Charlotte Maxeke and Steve Biko hospitals. The outsourcing programme should be able to ensure that patients who are currently awaiting treatment in the public sector will be able to access private sector treatment instead.
In their announcement, Gauteng Health stated: “We recognise the urgency of the situation and want to assure the public that we are committed to handling the outsourcing of radiation oncology sources diligently and are nearing implementation.”
The open tendering process will last 14 days, and is divided into categories for oncology specialists, treatment services and radiation planning services.
The department has already procured 4 Llinac machines, and has recently closed a tender for a Brachytherapy, and have advertised a tender for another Linac machine for Charlotte Maxeke. Ongoing investigations by Spotlight have also revealed that the oncology procurement process is lagging behind. The GDoH aims to have the first treatments under the outsourcing programme to start in August 2023.
Scanning electron micrograph image of E. Coli bacteria. Credit: NIH
Scientists have found that pairing specific diets with disease-causing bacteria can create lasting immunity in mice without the costs of developing sickness, revealing a new potential vaccination strategy. Their findings, published in Science Advances, may lead to new vaccines that could promote immunity for those with diarrhoeal diseases and possibly other infections.
The body takes one of two defence strategies against bacterial infections: kill the intruders or impair the intruders but keep them around. If the body chooses to impair the bacteria, then the disease can occur without the diarrhoea, but the infection can still be transmitted – also known as asymptomatic carriage.
“We discovered that immunisation against diarrhoeal infections is possible if we allow the bacteria to retain some of its disease-causing behaviour,” says senior author Professor Janelle Ayres at Salk Institute. “This insight could lead to the development of vaccines that could reduce symptoms and mortality, as well as protect against future infections.”
In 2018, Ayres’ lab looked at how dietary interventions can create an asymptomatic infection, which Ayres calls a cooperative, asymptomatic relationship between bacteria and host. They discovered that an iron-rich diet enabled mice to survive a normally lethal bacterial infection without ever developing signs of sickness or disease. The high-iron diet increased unabsorbed glucose in the mice’s intestines, which the bacteria could feast on. The excess glucose served as a ‘bribe’ for the bacteria, keeping them full and incentivised to not attack the host.
This process produced long-term asymptomatic infection with the bacteria, leading the researchers to believe that the adaptive immune system (which ‘remembers’ infections) may be involved.
“Being able to generate lasting immunity against bacteria like C. rodentium or E. coli has not been possible using established vaccination strategies. We wanted to figure out what mechanism was sustaining this lasting immunity, so we could use that mechanism to create an impactful solution to these diarrheal diseases,” says first author Grischa Chen, a former postdoctoral researcher in Ayres’ lab.
The researchers moved to figure out how the body suppresses infection symptoms, whether infection without symptoms can create long-term immunity, and whether that immunity is reproducible as a vaccination strategy.
The team compared mice with iron-rich and normal diets after C. rodentium infection to find whether the diet impacted symptomless infection. Immediately after infection, mice fed an iron-rich diet had no symptoms whereas mice fed a normal diet did have symptoms. All mice were then put on a normal diet to see whether the asymptomatic infection would last.
Mice without functional adaptive immune systems, regardless of whether they had ever been on an iron-rich diet, could not continue maintaining a cooperative relationship with the bacteria. Although the iron-rich diet suppressed symptoms immediately after infection, the adaptive immune system was required for lasting cooperation. Importantly, the mice with functional adaptive immune systems had the disease without any symptoms, with lasting immunity, as demonstrated by survival upon reinfection after a month.
Ayres and team concluded that an iron-rich diet alone can prevent bacteria from creating deadly symptoms in mice during active infection. But a functional adaptive immune system is required for immunity against future infection in the absence of dietary supplementation.
Some bacterial strains, if mutated enough, don’t cause symptoms. To test whether such bacteria could produce lasting immunity, the team repeated their iron-diet versus normal-diet experiment in mice, but this time using bacteria that could cause disease and bacteria that could not cause disease. They found that only mice that received disease-causing, unmutated bacteria were able to support immunity upon reinfection.
The scientists note that this is only a preliminary study and people shouldn’t consume large amounts of iron after reading it. They also hope their insights will provide a basis for future research in humans and the creation of a vaccination regiment that protects and prevents against diarrhoeal illness.
Researchers studying mice to investigate scarring in kidneys and hearts have found that it is driven by a protein called Indian Hedgehog (IHH), which is produced and released by a subset of cells in aged and injured kidneys. They published their findings in the journal Science Translational Medicine.
The researchers believe that IHH could become a potential target for therapies to treat chronic kidney disease (CKD) – a condition that affects 10% of the world’s population.
Risk factor
CKD is a term used to cover any form of kidney disease that continues for more than a few months. It can affect people of any age, but older people are more likely to experience some level of CKD.
While CKD primarily causes damage to kidneys, it is also a major risk factor for accelerated cardiovascular disease and premature death.
Progressive fibrosis – scarring of the kidneys – is a common feature in all CKD, but the mechanism underlying this connection is not fully understood.
Reduced scarring
A team from the University of Edinburgh identified a subset of epithelial cells that produce IHH and are only present within aged or injured mouse kidneys. They showed that these cells produced IHH in response to being activated by the protein TNF – a well-recognised driver of inflammation.
When blocking the actions of TNF or IHH in mouse models of kidney scarring, the team found that scar production in the kidney was reduced and kidney function was also better preserved. Increased levels of scarring in the heart also returned to normal levels.
Blocking pathway
In humans, the team showed that circulating IHH levels were significantly raised in patients with CKD. Patients with cardiovascular disease also had higher levels of IHH than those without cardiac problems.
The findings offer hope that blocking the TNF/IHH signalling pathway could improve both kidney and heart fibrosis problems – the leading cause of morbidity and mortality in patients with CKD.
There is a major unmet need for better treatments to halt the progressive kidney scarring and cardiovascular problems which affect so many patients with CKD. I’m excited at the potential of this work, and the new insights to be gained into the role of IHH as a major driver of multi-organ fibrosis, which we hope can be a first step on the road towards better treatments for patients.
Dr David Ferenbach, MRC Senior Clinical Fellow at the University of Edinburgh
Around 20% of women who needed fertility treatment, such as IVF, to conceive their first child are likely to get pregnant naturally in the future, finds a new study published in Human Reproduction. University College London researchers analysed data from 11 studies of over 5000 women around the world between 1980 and 2021, to evaluate how common it is to get pregnant naturally after delivering a baby conceived by fertility treatment.
They found that at least one in five women conceived naturally after having had a baby using fertility treatment such as IVF mostly within three years. This figure remained unchanged, even when taking into account the different types and outcome of fertility treatment – alongside length of follow up.
Infertility is defined by the failure to achieve a pregnancy after 12 months or more of regular unprotected sexual intercourse, and it is estimated to affect one in seven heterosexual couples.
However, not all women seeking and undergoing fertility treatment are absolutely or permanently infertile. And half of couples who struggle to conceive naturally in the first year of trying will go on to do so in the second year.
Not so rare an occurrence
Although it is typically considered ‘rare’ for a woman to get pregnant naturally, if she has previously had fertility treatment, the researchers want to highlight how it is not in fact an unusual event.
The team consider the findings to be particularly important, as many women may not realise that they could conceive naturally following fertility treatment. This could lead to them becoming pregnant again quickly or when they aren’t ready – which could be problematic for both the health of the mother and child.
Lead author, Dr Annette Thwaites (UCL EGA Institute for Women’s Health) said: “Our findings suggest that natural pregnancy after having a baby by IVF is far from rare. This is in contrast with widely held views – by women and health professionals – and those commonly expressed in the media, that it is a highly unlikely event.”
Much has changed since the early days of IVF and it is now used for a wide range of causes of infertility, including cases where no cause is ever found.
In addition, some women may not have experienced infertility at all but used treatment for other reasons. This could include single women using donor sperm, women in same sex relationships, surrogates or those seeking to screen for serious genetic conditions.
So, it is important for those who have had successful IVF to know how likely they are to conceive naturally afterwards.
IVF was first used in 1978 and now, more than 10 million babies worldwide have been born using the treatment – equating to between 1% and 6% of all babies born per year in the developed world by 2020.
In order to track the data more accurately and analyse which factors make natural pregnancy after having a baby by fertility treatment more likely, the researchers are calling for linked national data sets.
They hope that this information could then be used to counsel people considering their options after successful fertility treatment.
Dr Thwaites said: “Knowing what is possible would empower women to plan their families and make informed choices regarding further fertility treatment and/or contraception.”
Study limitations
Some limitations were the included studies being mostly of moderate quality with wide variation in geography, cause of subfertility, type and outcome of fertility treatment and length of follow up making direct comparisons difficult.
