ETH researchers from the Functional Materials Laboratory have developed a silicone heart that beats almost like a human heart. In collaboration with colleagues from the Product Development Group Zurich, they have tested how well it works.
It looks like a real heart. And this is the goal of the first entirely soft artificial heart: to mimic its natural model as closely as possible. The silicone heart has been developed by Nicholas Cohrs, a doctoral student in the group led by Wendelin Stark, Professor of Functional Materials Engineering at ETH Zurich. The reasoning why nature should be used as a model is clear. Currently used blood pumps have many disadvantages: their mechanical parts are susceptible to complications while the patient lacks a physiological pulse, which is assumed to have some consequences for the patient.
“Therefore, our goal is to develop an artificial heart that is roughly the same size as the patient’s own one and which imitates the human heart as closely as possible in form and function,” says Cohrs. A well-functioning artificial heart is a real necessity: about 26 million people worldwide suffer from heart failure while there is a shortage of donor hearts.  Artificial blood pumps help to bridge the waiting time until a patient receives a donor heart or their own heart recovers.
The soft artificial heart was created from silicone using a 3D-printing, lost-wax casting technique; it weighs 390 grams and has a volume of 679 cm3. “It is a silicone monoblock with complex inner structure,” explains Cohrs. This artificial heart has a right and a left ventricle, just like a real human heart, though they are not separated by a septum but by an additional chamber. This chamber is in- and deflated by pressurized air and is required to pump fluid from the blood chambers, thus replacing the muscle contraction of the human heart.
Anastasios Petrou, a doctoral student of the Product Development Group Zurich, led by Professor Mirko Meboldt evaluated the performance of this soft artificial heart.
They proved that the soft artificial heart fundamentally works and moves in a similar way to a human heart. However, it still has one problem: it currently lasts for about only 3,000 beats, which corresponds to a lifetime of half to three quarters of an hour. After that, the material can no longer withstand the strain. Cohrs explains: “This was simply a feasibility test. Our goal was not to present a heart ready for implantation, but to think about a new direction for the development of artificial hearts.” Of course, the tensile strength of the material and the performance would have to be enhanced significantly.

ETH Zurich
www.ethz.ch/en/news-and-events/eth-news/news/2017/07/artificial_heart.html

New evidence suggests low-cost drug should become frontline response for major blood loss after childbirth.

An inexpensive and widely available drug could save the lives of one in three mothers who would otherwise bleed to death after childbirth, according to a major study.

The global trial of 20,000 women found that death due to bleeding was reduced by 31percent if the treatment was given within three hours.

The drug, called tranexamic acid (TXA), works by stopping blood clots from breaking down. The findings also show it reduced the need for urgent surgery to control bleeding (laparotomy) by more than a third (36percent).

Severe bleeding after childbirth (known as post-partum haemorrhage or PPH) is the leading cause of maternal death worldwide. More than 100,000 women globally die each year from the condition, but this clot-stabilising drug has the potential to reduce the number substantially.

The WOMAN (World Maternal Antifibrinolytic) Trial recruited mothers from 193 hospitals in 21 countries, mainly in Africa and Asia, but also in the UK and elsewhere. The London School of Hygiene & Tropical Medicine coordinated the trial. It was funded by The Wellcome Trust and UK Department of Health through the Health Innovation Challenge Fund, and the Bill & Melinda Gates Foundation.

The results show that of the women given tranexamic acid within three hours, 89 died from bleeding compared with 127 given placebo (in addition to standard care). The researchers found no side effects from the drug for either mothers or babies. These findings provide the first comprehensive evidence on using tranexamic acid for post-partum haemorrhage and suggest it should be used as a frontline treatment.

Haleema Shakur, Associate Professor of Clinical Trials at the London School of Hygiene & Tropical Medicine and Project Director on the WOMAN Trial, said: ‘We now have important evidence that the early use of tranexamic acid can save women’s lives and ensure more children grow up with a mother. It’s safe, affordable and easy to administer, and we hope that doctors will use it as early as possible following the onset of severe bleeding after childbirth.’

Tranexamic acid was invented in the 1960s by a Japanese husband and wife research team, Shosuke and Utako Okamoto.

London School of Hygiene & Tropical Medicinewww.lshtm.ac.uk/newsevents/news/2017/woman_trial_results.html

Researchers presenting a preclinical study at the 2017 Annual Meeting of the Society of Nuclear Medicine and Molecular Imaging (SNMMI) demonstrated the efficacy and optimal dose for targeted photodynamic therapy (tPDT) to treat prostate cancer before and during surgery. Prostate-specific membrane antigen (PSMA) was targeted with an anti-PSMA antibody radiolabeled with the tracer indium-111 (111In) and coupled with specialized photosensitizers that cause cell destruction upon exposure to near-infrared (NIR). The combined formula is 111In-DTPA-D2B-IRDye700DX.
“Coupling the photosensitizer to an imaging agent that targets PSMA on the tumour surface makes it possible to selectively and effectively destroy prostate tumour remnants and micrometastases while surrounding healthy tissues remain unaffected,” said Susanne Lütje, MD, PhD, lead author of the study from the Department of Radiology and Nuclear Medicine at Radboud University Medical Center in Nijmegen, the Netherlands, and the Clinic for Nuclear Medicine at University Hospital Essen, Germany.
This technique optimizes prostate cancer care by allowing visualization of tumours prior to surgery, by providing real-time guidance to surgeons in the operating room, and by priming tumours for photodynamic therapy when surgery isn’t enough or risks damage to sensitive structures.
A gamma probe is used to detect PSMA-expressing tumour cells. Photosensitizers can then be activated with light in the near-infrared wavelength, which causes them to emit fluorescence, or oxygen radicals, that damage PSMA over-expressing tumour tissues.
Study results showed effective localization of the drug at the site of tumours, as well as effective imaging and photodynamic therapy via near-infrared exposure in mice. Further study in humans is needed before this procedure could be made available for prostate cancer patients.
“In the future, this novel approach to prostate cancer could significantly improve the effectiveness of treatment, reduce recurrent disease and ultimately prolong survival and protect quality of life for patients,” said Lütje.

Society of Nuclear Medicine and Molecular Imaging
www.snmmi.org/NewsPublications/NewsDetail.aspx?ItemNumber=24264

For the first time, researchers have shown that using Magnetic Resonance Imaging (MRI) can effectively identify bone marrow cancer (myelofibrosis) in an experimental model. The finding may change the way this disease is diagnosed which is now through invasive bone marrow biopsies.
Myelofibrosis is a slow evolving condition hallmarked by increased myeloid cells and in the case of primary myelofibrosis, with an excessive number of large bone marrow cells called megakaryocytes. The pathology also is characterized by structural abnormality of the bone marrow matrix, which at end-stage manifests in excessive deposition of reticulin fibres and cross-linked collagen in the bone marrow, suppression of normal blood cell development and bone marrow failure. Currently the diagnosis is made via an invasive bone marrow biopsy and histophatology to assess cellularity and reticulin deposition in the marrow.
Researchers at Boston University School of Medicine (BUSM) led by Katya Ravid, PhD, designed and tested whether a T2-weighted MRI could detect bone marrow fibrosis in an experimental model. The group was able to show that an MRI could detect a pre-fibrotic state of the disease with a clear bright signal, as well as progressive myelofibrosis. The investigators proposed that the abundance of large megakaryocytes contribute to the signal, since in T2-weighted MR-images, increased water/proton content, as in increased cellularity, yield high (bright) MR-signal intensity.
This is the first study to evaluate a T2-weighted MRI in an experimental model of myelofibrosis with examination of potential sources of the MRI signal, researchers said. “Our study provides proof-of-concept that this non-invasive modality can detect pre-fibrotic stages of the disease,” said Ravid, professor of medicine and biochemistry at BUSM. “It is intriguing to speculate that future pre-biopsy MRI of the human pathology might guide in some cases decisions on if and where to biopsy,” she added.

Boston University School of Medicinehttp://tinyurl.com/y74qq8pv