Erikson’s Stages of Psychosocial Development are super super super important to memorize. (mostly the years and the basic conflict) i’ve had a ton of these questions in KAPLAN so far.
Human Stem Cells Converted to Functional Lung Cells
Dec. 1, 2013 — For the first time, scientists have succeeded in transforming human stem cells into functional lung and airway cells. The advance, reported by Columbia University Medical Center (CUMC) researchers, has significant potential for modeling lung disease, screening drugs, studying human lung development, and, ultimately, generating lung tissue for transplantation. The study was published today in the journal Nature Biotechnology.
Which superfoods really have super powers? An interactive data-visualisation of the best scientific evidence we could find.
Scientific evidence behind health benefits of certain foods
Working out for a half hour, 3(ish) days a week, walking a smidge and eating as well as you can without being too diligent might NOT get you to your aesthetic goals, flat abs, a goal weight or the podium/finish line. That’s true. Those things often need more effort for most…
An invention to help with obstructed labor has turned some heads — and not just because the idea came from a party trick on YouTube.
The Odon Device, created by Argentine car mechanic Jorge Odon, guides a folded plastic sleeve around the baby’s head. A little bit of air is then pumped between the two plastic layers, cushioning the baby’s head and allowing it to be sucked out. This trick for removing a cork from an empty wine bottle works the same way.
The device has been embraced by the World Health Organization and is being developed by the global medical technology company BD. Once clinical trials are done, the WHO and individual countries will have to approve it before it’s sold. BD hasn’t said how much it will charge, but each one is expected to cost less than $50 to make.
"If proven safe and effective," a 2011 presentation on Odon’s invention said, “the Odon Device will be the first innovation in operative vaginal delivery since the development of forceps centuries ago and vacuum extractor decades ago.”
The Odon device shows that “good ideas can come from anyone and anywhere,” says Wendy Taylor, director of USAID’s Center for Accelerating Innovation and Impact.
If you’re in the business of innovating, she says, there’s no need to strive for mechanical complexity. Some of the biggest breakthroughs are cheap and simple. And, she says, the strategy for scaling something up for worldwide use “is just as important as the innovation itself.”
One of the crowning innovations in preventing death during childbirth was convincing doctors to wash their hands in between handling corpses and delivering babies. And many argue that fancier tools are just part of a tradition of unnecessary interference that circumvented the best tool in the box: gravity.
With that in mind, here are five ideas that struck us as innovative and surprising (some more likely to succeed than others):
1. Ready Yet?
A team at the University of California, San Francisco created a “cervical cap" to check whether a woman is about to go into labor. The device can detect changes in the collagen of the cervix. The softening of collagen as the cervix opens is a telltale sign a baby’s on its way. Information from the cap’s sensors can be transmitted to a nearby cellphone, which can send the data to a doctor. The device can be inserted briefly once a day, without a professional’s help.
2. Back To Basics
A team at Massachusetts General Hospital developed a uterine balloon kit to stop postpartum hemorrhage. It consists of a condom tied to a catheter. Water from the catheter fills the condom in the uterus, creating pressure that can stop the bleeding. The kit has been tested successfully in South Sudan and Kenya. A similar tool in the U.S. can cost more than $300 each, Mass General says, compared with less than $5 each for the simple balloon kit.
Top Drawing: The Odon Device was inspired by a YouTube video about how to remove a cork from the inside of a wine bottle. (Courtesy of the Odon Device)
Bottom Drawing: A ”cervical cap" detects changes in the collagen of the cervix to determine if a baby’s on its way. Information from the cap’s sensors can be transmitted to a nearby cellphone, which can send the data to a doctor. (Courtesy of UCSF)
CHRONIC & END-STAGE RENAL FAILURE
- Progression of Acute Kidney Injury if left untreated will lead to chronic renal failure.
- Permanent, irreversible loss of function
- Early Na+ depletion, Late Na+ retention
- REMEMBER ALL OF THE FUNCTIONS OF THE KIDNEY?? THEN IMAGINE THE KIDNEY NOT BEING ABLE TO DO ITS JOB!
- Fluid Balance
- Removal of wastes
- Electrolyte balance Na+, K+, Ca+ Phosphorus
- Acid Base (making and conserving bicarb)
- BP Control if kidneys don’t get blood flow > RENIN > RAAS
- Adrenal Glands produce Aldosterone
- Activate Vitamin D
- Produce Erythropoitin which tells bones to release RBC
- Acid-base imbalance: loss nephrons > loss compensation for acid load > HCO3 deficit > metabolic acidosis
- Ca+/PO4 imbalances Sx: hypocalcemia *HINT*: Chvosteks and Trousseaus are signs of hypocalcemia
Medical Management of Renal Failure
- Fluids (RESTRICT)
- Electrolytes (^K, Na+, PO4)
- Nutritional Concerns
- (decrease protein, K+, Na+, PO4) but INCREASE CALORIES, (FAT + CHO)
LIMIT THE 3 P’s !!
- Avoid: organ meats, fish, dried fruits, beef, chicken, pork, milk, dark green vegetables, salt substitutes.Phosphorus
- Avoid: milk, cheese, yogurt, collard greens, dried beans
- Valvulation of protein restriction based on body weight. Dialysis status (protein is lost)
- Avoid: processed foods, fast foods, potato chips, pretzels, pickles, ham, bacon, sausage
Medical Management PHARMACOLOGICAL
- Treat HTN
- Treat Volume
- Admin Folic Acid & Ferrous Sulfate
- Po4 binders (to excrete phosphorus to raise CA+)
- Increase CA+ sources
- Stool softeners & Laxatives
INDICATIONS FOR DIALYSIS : “ HAVE PEE ”
- Hyperkalemia (refractory) doesn’t respond to therapy
- Acidosis (refractory) bicarb drip?
- Volume overload
- Elevated BUN (w/ s/sx of complications > uremic toxins, uremic crystals, pruritus)
- Encephalopathy (w/ALOC/mentation) uremic coma
- Edema (pulmonary.
HIV-1 evades the immune system with a protein shield, which can be lifted.
HIV-1, the virus that causes AIDS, is renowned for its ability to escape the immune system. A new study shows that its sneaky talents depend on the capsid protein that makes up the virus’s outer coat.
Xavier Lahaye and Takeshi Satoh from the Institut Curie in Paris showed that HIV-1 uses its capsid to cloak its DNA from dendritic cells—sentries that detect incoming threats and mobilize the immune system. The researchers also managed to lift this immunity cloak by mutating the capsid.
“By playing with the capsid, we made an HIV-1 that does not replicate but can stimulate an immune response,” said Nicolas Manel, who led the study. “We could imagine modifying the virus and using it as a vaccine.” The results are published today in Immunity.
“It’s a very nice piece of work,” said Greg Towers from University College London, who was not involved in the study but recently published similar results. “I think we’re all on the same page, and there’s a paradigm shift in our understanding of how HIV interacts with the immune system. We used to think that the capsid came off the virus when it entered the cell, and its job was done. It turns out that it also protects the virus’s DNA from being seen.”
Dendritic cells can recognize viruses that infect them with a range of sensor molecules, and they instruct other parts of the immune system to target these threats. “They are the key orchestrators of the immune response,” said Manel. “They’re first to detect pathogens and direct what happens after that.”
Back in 2010, Manel’s team showed that dendritic cells can detect HIV-1 under some circumstances, although this is atypical because the virus does not usually infect the cells efficiently. By contrast, a related virus called HIV-2 does fully infect dendritic cells and triggers a strong immune response. This partly explains why HIV-1 can evade the immune system and cause AIDS, while HIV-2 does not.
The team wanted to find out how the dendritic cells were detecting the viruses, and which parts they were sensing. They began by tweaking HIV-2’s capsid, and found that changing a single amino acid produced a virus that cannot infect dendritic cells but can still be detected by them. This implied that detection takes place at an early part of the virus’s life cycle, before it has a chance to make copies of itself.
Once HIV-1 and HIV-2 enter cells, they copy their RNA genome into a DNA molecule that is integrated into the genetic material of their host. The team found that this DNA is what the dendritic cells detect. “You need synthesis of DNA for detection, but you don’t need the steps after,” said Manel.
The team also identified the sensor molecule—a protein called cGAS, which was discovered by investigators at University of Texas Southwestern Medical Center in Dallas this year. When cGAS detects viral DNA in dendritic cells, it triggers a chain of molecular signals that marshals an immune response.
That explains HIV-2, but how does HIV-1 evade detection? The team showed that the capsid somehow masks the viral DNA, preventing cGAS from sensing it. This allows the DNA to integrate into the host’s genome, be copied, and produce new virus particles.
The team managed to peel back this invisibility cloak by mutating the capsid, leaving HIV-1’s DNA exposed and visible to the cGAS sensors. This suggested that similar modified viruses may, after much development, form the basis of a vaccine. This modification happens naturally to an extent—people who are infected with HIV-1 live longer if they had previously been infected with HIV-2, and are less likely to proceed to develop AIDS.
Alternatively, “we can think about small chemical compounds that stimulate this pathway and mimic the immune response,” said Manel.
“The study highlights the importance of studying HIV-2 [to increase] our understanding of underlying mechanisms important for HIV-1 pathogenesis,” added Joakim Esbjörnsson from Lund University in an e-mail.
Image: WIKIMEDIA, NIH