Welcome back to The Vitals Podcast; I’m your host, Chauncey, back yet again to digest and bring you the latest in medical news today. It is Monday, May 27, 2024, and I have even more innovations to dig through with you. As always, don’t forget to follow the podcast and share it with your friends to keep everyone you know updated on the latest medical breakthroughs.
Our first study comes from Dr. Ajay Goel and his colleagues at City of Hope Cancer Center in Duarte, California, who have perfected a blood test to detect pancreatic cancer early.
Pancreatic cancer, specifically pancreatic ductal adenocarcinoma (PDAC), is a rather tricky cancer; in early stages, it doesn’t present with any conspicuous symptoms, and established tests to check for it aren’t incredibly reliable. Catching it early, however, is a key factor in the cancer’s prognosis; chances of living for at least five years after diagnosis drop from 44% in early stage disease to only 3% in late stage. There’s a need for an accurate and simple test to detect early stage cancer, and Dr. Goel may have provided.
The blood test, called a liquid biopsy, developed by Dr. Goel detects tumor-derived exosomal micro-RNAs; that’s a mouthful, so let’s break it down. Micro-RNAs are a special type of RNA that serves as a translation regulator. Translation is the process of turning mRNA into protein. Micro-RNA splices or destabilizes mRNA so that it only makes as much protein as needed. Micro-RNAs are also sent between cells to regulate each other’s translation, acting as tumor suppressors, OR as messages between cells. To do this, they’re excreted out of the cell through a small sac called an exosome, making the micro-RNAs inside ‘exosomal micro-RNAs’.
The micro-RNAs that are released from cancerous cells (or ‘tumor-derived exosomal micro-RNAs’) are unique in that it, firstly, disrupts the immune system and its ability to attack the cancer, and secondly, acts as oncogenes, meaning it potentially promotes cancerous growth. More importantly, however, these exosomes essentially send away a small piece of the cancerous cell it came from, which can be collected and used to diagnose patients. This is the idea behind the liquid biopsy.
Testing this in a cohort of 95 individuals from Japan and the US, some with PDAC and some healthy, they reported a 98% detection rate. They continued this study using a larger sample size from three nations: the United States (139 with PDAC; 193 healthy donors); South Korea (184 with PDAC; 86 healthy donors); and China (50 with PDAC; 80 healthy donors). The detection rate here was 93% in the U.S. cohort; 91% in the South Korean cohort; and
88% in the Chinese cohort. In contrast, a test looking for an antigen called CA19-9 is only 86% accurate. Using data from the U.S. cohort, combining both tests together reported to be 97% accurate.
This test is a new tool in the battle against not only PDAC, but other cancers as well. Detecting the disease early is imperative to outcome and treatment, so this test will prove invaluable to the well-being of cancer patients.
An Exosome-based Transcriptomic Signature for Noninvasive, Early Detection of Patients With Pancreatic Ductal Adenocarcinoma: A Multicenter Cohort Study – PubMed (nih.gov) (<– Original Study)
AACR Annual Meeting 2024 Itinerary Planner | Presentation (abstractsonline.com)
microRNA-Based Liquid Biopsy Detects Early Pancreatic Cancer – NCI
An Exosome-based Liquid Biopsy Shows Promise for Early Detection of Pancreatic Cancer (aacr.org)
Our second study comes from researcher Lizheng Guan and his team of colleagues at the University of Wisconsin-Madison and the Texas A&M Veterinary Medical Diagnostic Laboratory who are assessing the risk of infection from a pathogenic strain of avian flu through contaminated cow milk.
In recent news, at least two cases of Highly Pathogenic Avian Influenza H5N1 virus (or HPAI H5N1) have been recorded; one in Michigan and one in Texas. Both cases are of farm workers exposed to infected dairy cattle, or cows. Strangely enough, the patients have complained of symptoms in line with an eye infection, namely conjunctivitis, or pink eye; an eye swab of the Michigan case revealed it to be H5 Bird Flu, the name given by the CDC.
Additionally, a nasal swab was taken from the Michigan case, and came up negative. The CDC has added conjunctivitis as an official part of the virus’s case description next to normal flu symptoms. It also lists the public health risk as low because, firstly, the virus is not very transmissible from human to human, and secondly, the initial leap from cow to human is believed to have come from contaminated unpasteurized milk spilling on the patients’ hand, which they may have touched their eyes with. Milk from infected cows must be disposed of, and even so, milk is pasteurized at 72°C (~145°F) for at least 15 seconds, or 63°C (~161°F) for at least 30 minutes before being packaged.
The study conducted by Guan and his team saw them feed droplets of raw milk from infected cows to five mice. On Day 1, they showed signs of infection. They survived to Day 4 and were euthanized to determine their organ virus levels. The researchers discovered high levels of virus in the mice’s nasal passages, trachea and lungs and moderate-to-low virus levels in other organs, as expected.
They then tested to see which temperatures and time intervals were most effective at inactivating the virus in raw milk. Four milk samples with confirmed high virus levels were tested at 63°C for 5, 10, 20 and 30 minutes, or at 72°C for 5, 10, 15, 20 and 30 seconds. Each of the time intervals at 63℃ successfully killed the virus. At 72℃, virus levels were diminished but not completely inactivated after 15 and 20 seconds. In a separate experiment, the researchers concluded that the H5 virus can also remain infectious for several weeks in raw milk kept at 4°C (~39°F).
Overall, the researchers summarized that contaminated milk poses a risk when consumed untreated, and points out that the lab experiments of heating milk do not replicate the conditions at industrialized pasteurization facilities. As for the H5 Bird Flu in humans, the CDC is committed to keeping an eye on its activity until further notice.
Cow’s Milk Containing Avian Influenza A(H5N1) Virus — Heat Inactivation and Infectivity in Mice | New England Journal of Medicine (nejm.org) (<– Original Study)
High H5N1 influenza levels found in mice given raw milk from infected dairy cows | ScienceDaily
Now, it is time for THE VITALS, where I go in-depth on what you need to know about topics of your choice. If you’d like your question to be answered, drop it down in the Q&A, and you may see it in a future episode!
This episode’s vital question comes from Kings, who asks, “How have robots integrated into the medical field?”
Great question, Kings. When we think of robots in medicine, we think of the more recent automated systems on the practitioner side; that is, robots for dispensing medication, transporting patients, patient screening, sterilization, and on and on and on. There are also robotic systems for pacemakers, ventilators, prosthetics, and imaging. In fact, the first robot used in medicine, PUMA 560, was for a brain biopsy way back in 1985 using robotic precision to eliminate human error. In 1988, PROBOT helped surgeons during prostate surgery; systems like Neuro-Mate, Minerva, and the Robot-Assisted Microsurgery System were made in the 1990s. In 1992, ROBODOC assisted practitioners during a leg operation. Many robotic systems that are used in medicine today were invented and approved in the 2000s.
Laparoscopic surgery is the opposite of open surgery; instead of cutting open a patient, surgeons poke holes into the patient’s abdomen, insert a small camera called a laparoscope, pump the abdomen with air, and insert small surgical tools to carry out the procedure with minimal risk. In 2000, the first Da Vinci Surgical System was approved by the FDA for general laparoscopic surgery. The newest system, the Da Vinci Xi was developed in 2018 and still is in wide use today. Intuitive Surgical, the developers of the Da Vinci Xi, are planning to release the Da Vinci 5 in 2025, using the newest and latest technology.
The Da Vinci Xi works like an extension of the surgeon’s hands. The robot has four arms, three of which can hold many different surgical tools, and a fourth that holds the system’s 3D cameras. The surgeon operates with the Da Vinci by using instruments that they guide via a console. The Da Vinci system translates the surgeon’s hand movements at the console in real time, bending and rotating the instruments while performing the procedure. The tiny wristed instruments move like a human hand, but with a greater range of motion, which allows the Da Vinci Xi to be used for a wide range of surgeries.
Thanks, Kings, for the question!
That’s all for this week’s episode, so thank you for tuning in, and a special thank you to my friend Nilesh for sharing your experience with us! Follow the podcast and share this episode with your friends! If you’d like your questions answered, remember to drop a response in the Q&A section of this video. Until next time, keep your vitals strong and your spirits high. This is your host Chauncey signing off. Take care and stay healthy, I’ll see you next week!
Anxiety weighs down the heart, but a kind word cheers it up.
Proverbs 12:25 NIV