Archiv der Kategorie: Biologie

Tiny Wearable Biosensor Continuously Monitors Your Body Chemistry

Imagine, throughout your day, you could know exactly what your body chemistry was up to. More specifically, imagine if the information from your body could instantly go to your doctor and he could make a diagnosis of what your body was doing or what was wrong.

It’s nearly here. Today at CES 2016, a company called Profusa demonstrated a wearable biointegrated sensor, Lumee, that allows for long-term continuous monitoring of your body chemistry. This wearable smart tech device provides actionable data on your body’s key chemistry in one continuous data stream which changes the way we will monitor our health.

Lumee, a biointegrated wearable sensor.

Lumee, a biointegrated wearable sensor.

“In between annual physicals we really don’t know what’s going on in our body,” said Ben Hwang, Ph.D., CEO, Profusa. “While fitness trackers and other wearables provide insights into our heart rate, respiration and other physical measures, they don’t provide information on the most important aspect of our health: our body’s chemistry. What if there was a better way of knowing how you’re doing — how you’re really doing?”

According to Statista, the digital health market is expected to reach $233.3 billion by 2020, and that market is being led by the mobile health market.

Since the iPhone hit it big in 2007, consumers and physicians alike (52%) use their smartphone to search for advice, drugs, therapies, etc, and 80% of physicians use smartphones and medical apps. With wearables, physicians can now collect long-term and specialized data that’s much easier to obtain and track patient health behaviors over longer periods of time. This has already changed our relationship with our health care providers and their relationships with us.

“Profusa’s Lumee is a bold attempt at one of the holy grails of personalized medicine, continuous, real time, non-invasive glucose and oxygen monitoring, it’s applications are vast,” said Ryan Bethencourt, Program Director and Venture Partner at Indie.Bio, a bio-tech accelerator in San Francisco. “From Type 1 and Type 2 diabetes monitoring through to fitness and finding optimal training patterns for your body, with data that’s currently impossible to acquire any other way continously. I’m rarely this optimistic about a new medical device, especially one that will require implantation approval from the FDA but in this case, I think the optical biosensor technology and device design warrant the optimism.”

This is why Profusa hopes their tiny (3-5 mm) bioengineered biosensors will enable real-time detection of our body’s unique chemistry in order to give greater insight into a person’s overall health status. Dr. Hwang believes Lumee can be applied to consumer health and wellness applications but also to the management of chronic diseases like Peripheral ArteryDisease (PAD), diabetes and Chronic Obstructive Pulmonary Disease (COPD).

http://www.forbes.com/sites/jenniferhicks/2016/01/07/beyond-fitness-trackers-at-ces-tiny-wearable-biosensor-continuously-monitors-your-body-chemistry/#67cc511a6019

HIV Genes Successfully Edited Out of Immune Cells

HIV Genes Successfully Edited Out of Immune Cells
An electron micrograph of HIV particles infecting a human T cell. Image: National Institute of Allergy and Infectious Diseases

Researchers from Temple University have used the CRISPR/Cas9 gene editing tool to clear out the entire HIV-1 genome from a patient’s infected immune cells. It’s a remarkable achievement that could have profound implications for the treatment of AIDS and other retroviruses.

When we think about CRISPR/Cas9 we tend to think of it as a tool to eliminate heritable genetic diseases, or as a way to introduce new genes altogether. But as this new research shows, it also holds great promise as a means to eliminate viruses that have planted their nefarious genetic codes within host cells. This latest achievement now appears in Nature Scientific Reports.

Retroviruses, unlike regular run-of-the-mill viruses, insert copies of their genomes into host cells in order to replicate. Antiretroviral drugs have proven effective at controlling HIV after infection, but patients who stop taking these drugs suffer a quick relapse. Once treatment stops, the HIV reasserts itself, weakening the immune system, thus triggering the onset of acquired immune deficiency syndrome, or AIDS.

Over the years, scientists have struggled to remove HIV from infected CD4+ T-cells, a type of white blood cell that fights infection. Many of these “shock and kill” efforts have been unsuccessful. The recent introduction of CRISPR/Cas9 has now inspired a new approach.

Geneticist Kamel Khalili and colleagues from Temple University extracted infected T-cells from a patient. The team’s modified version of CRISPR/Cas9—which specifically targets HIV-1 DNA—did the rest. First, guide RNA methodically made its way across the entire T-cell genome searching for signs of the viral components. Once it recognized a match, a nuclease enzyme ripped out out the offending strands from the T-cell DNA. Then the cell’s built-in DNA repair machinery patched up the loose ends.

Not only did this remove the viral DNA, it did so permanently. What’s more, because this microscopic genetic system remained within the cell, it staved off further infections when particles of HIV-1 tried to sneak their way back in from unedited cells.

The study was performed on T-cells in a petri dish, but the technique successfully lowered the viral load in the patient’s extracted cells. This strongly suggests it could be used as a treatment. However, it could be years before we see that happen. Still, the researchers ruled out off-target effects (i.e. unanticipated side-effects of gene-editing) and potential toxicity. They also demonstrated that the HIV-1-eradicated cells were growing and functioning normally.

These findings “demonstrate the effectiveness of our gene editing system in eliminating HIV from the DNA of CD4 T-cells and, by introducing mutations into the viral genome, permanently inactivating its replication,” Khalili said in a statement. “Further, they show that the system can protect cells from reinfection and that the technology is safe for the cells, with no toxic effects.”

This technique for snipping out alien DNA could have implications for related research, including treatments for retroviruses that cause cancer and leukemia, and the suite of retroviruses currently affecting companion and farm animals. As noted by Excision BioTherapeutics’ CEO and President Thomas Malcolm, “These exciting results also reflect our ability to select viral gene targets for safe eradication of any viral genome in our current pipeline of gene editing therapeutics.”

And Malcolm has good reason to be excited: his company holds exclusive rights to commercialize this technology.

http://gizmodo.com/hiv-successfully-edited-out-of-immune-cells-1766413957?rev=1458672609052

What Is inside McDonalds‘ French Fries?

McDonalds Fries

POTATOES

Mickey D’s uses varieties like the Russet Burbank, which have a nice oval shape and just the right balance of starch and sugar. Excess sugar can cause a fry to have brown spots where it’s over-caramelized, leaving a burnt taste and deviating from the uniform yellow-arches color. Just in case, the spuds are blanched after slicing, removing surplus sugar.

SODIUM ACID PYROPHOSPHATE

Taters can turn a nasty hue even after they’re fried—iron in the spud reacts with the potato’s phenolic compounds, discoloring the tissue. The phosphate ions in SAPP trap the iron ions, stalling the reaction and keeping the potatoes nice and white throughout the process.

VEGETABLE OIL

In the good old days, McDonald’s fries were cooked in beef tallow. But customer demand for less saturated fat prompted a switch to vegetable oil in the early ’90s. Here, that means oils of varying saturations combined into something reminiscent of beef tallow. There’s canola (about 8 percent saturated fat), soybean oil (16 percent), and hydrogenated soybean oil (94 percent). And to replace the essence of beef tallow? “Natural beef flavor,” which contains hydrolyzed wheat and milk proteins that could be a source of meaty-tasting amino acids.

MORE VEGETABLE OIL

That’s right, the fries get two batches of vegetable oil—one for par-frying at the factory and another for the frying bath on location. The second one adds corn oil and an additive called TBHQ, or tertbutylhydroquinone, which at high doses can cause nasty side effects in rats (mmmm … stomach tumors). McDonald’s uses this oil for all its frying, so the stuff usually sits around in big vats, which means it can go rancid as oxygen plucks hydrogens from lipids. TBHQ acts as an antioxidant, replacing those pilfered hydrogens with its own supply.

DEXTROSE

A brief dip in a corn-based sugar solution replaces just enough of the natural sweet stuff that was removed by blanching. The result is a homogeneous outer layer that caramelizes evenly. You’ll add more sugar later when you squirt on the ketchup.

SALT

Sprinkled on just after frying, the crystals are a uniform diameter—just big enough to get absorbed quickly by crackling-hot oil. Now add ketchup and you’ve achieved the hedonistic trifecta: fat, salt, and sugar.

Source: http://www.wired.com/2014/07/whats-inside-mcdonalds-french-fries/

A Logic-Gated Nanorobot for Targeted Transport of Molecular Payloads

DNA-Nanoroboter greift Krebszellen an

US-Forscher haben einen Nanoroboter gebaut, der gezielt Krebszellen angreifen kann. Die Miniaturmaschine nach dem Vorbild der körpereigenen Immunabwehr besteht aus geschickt gefaltetem Erbmaterial (DNA) und lässt sich im Prinzip für jede Zielzelle im Organismus maßschneidern.

Bisher ist der Roboter allerdings erst in Zellkulturen getestet worden. Ob er jemals bei Menschen zum Einsatz kommen kann, ist noch nicht geklärt. Ähnliche Ansätze verfolgen auch andere Forschergruppen

Der Nanoroboter gleicht einem sechseckigen Käfig, der nur 45 Nanometer (Millionstel Millimeter) hoch und 35 Nanometer dick ist – damit ist er rund 2.000 Mal dünner als ein menschliches Haar. Der mit einer speziellen Technik namens DNA-Origami gefaltete Käfig besteht aus zwei Hälften, die von Riegeln zusammengehalten werden. Diese Riegel sind so aufgebaut, dass sie ähnlich wie weiße Blutkörperchen die Oberfläche gewünschter Zielzellen – etwa Krebszellen – erkennen und daran andocken können. Mit dem Andocken konfiguriert der Riegel sich neu, so dass der Nanokäfig aufschwingt.

Der Laderaum lässt sich mit verschiedenen Wirkstoffen bestücken, die auf diese Weise gezielt zu ihrem Einsatzort gebracht werden können. Im Experiment belud das Team um Shawn Douglas von der Harvard-Universität in Boston seine Nanoroboter unter anderem mit molekularen Botenstoffen, die das Selbstmordprogramm einer Zelle aktivieren können. Dieses Programm ist bei Krebszellen typischerweise gestört.

Gezielte Zerstörung

Im Labor konnten die Forscher auf diese Weise die Selbstzerstörung bei Leukämie- und Lymphomzellen auslösen, wobei auch die molekularen Botschaften für die beiden verschiedenen Krebszellen maßgeschneidert werden mussten. Nach diesem Muster könnten verschiedene Aktionen gezielt bei gewünschten Zelltypen ausgelöst werden, erläutern die Wissenschaftler.

Die Forscher, die sich für ihre Arbeit von der Funktion des menschlichen Immunsystems inspirieren ließen, bereiten nach den Worten von Douglas als nächstes Tests an Versuchstieren vor. „Das wird wahrscheinlich ein verbessertes Design erfordern, um eine stabile Zirkulation und Funktion im Blutkreislauf zu gewährleisten“, schränkte der Forscher allerdings ein. „Außerdem müssen die Herstellungskosten des Geräts sinken.“

science.ORF.at/APA/dpa

Quellen:
http://www.sciencemag.org/content/335/6070/831.abstract

Artikelzitat aus:
http://science.orf.at/stories/1694726/

Interleukin-33 aktiviert Immunabwehr (CD8+ T Zellen Responses)

„Neue Erkenntnisse bieten vielversprechenden Ansatz für Impfungen gegen HIV, Hepatitis, Malaria und Krebs

Genf – Schweizer Wissenschafter haben ein Molekül entdeckt, das den Körper bei einer Virusinfektion zur effizienten Abwehrreaktion anregt. Der Mechanismus, bei dem T-Killerzellen im Blut aktiviert werden, könnte dabei helfen, neue Impfmethoden zu entwickeln.

Forscher um Daniel Pinschewer von der Uni Genf haben gemeinsam mit Kollegen aus Berlin einen neuen Mechanismus zum Ankurbeln der Immunreaktion nach einer Impfung entdeckt. Wie die Wissenschafter im US-Fachmagazin „Science“ berichten, wird diese Art der Immun-Alarmierung erst in Gang gesetzt, wenn ein Virus bereits bestimmte Körperzellen getötet hat.

Sterben diese Zellen ab, setzen sie unter anderem ein Eiweiß namens Interleukin 33 (IL-33) frei. Bei Mäusen wiesen die Forscher nach, dass erst IL-33 zu einer kräftigen Immunantwort durch T-Killerzellen, auch bekannt als cytotoxische T-Zellen, führt. Mäuse, die genetisch so verändert waren, dass ihr Immunsystem IL-33 nicht erkennen konnte, waren auch nicht in der Lage, die Infektion abzuwehren.

Vielversprechender Ansatz gegen HIV, Hepatitis und Krebs

Laut den Forschern könnte IL-33 benutzt werden, um zum Beispiel mit einer Impfung die Immunabwehr zu verstärken. Solche Impfmethoden sind laut ihnen nicht nur gegen Infektionskrankheiten wie HIV, Hepatitis oder Malaria vielversprechend, sondern auch gegen Krebserkrankungen. Denn T-Killerzellen können auch Tumorzellen abtöten.“

Quellen: http://www.sciencemag.org/content/early/2012/02/08/science.1215418.abstract
Artikelzitat aus: http://derstandard.at/1328507356183/Interleukin-33-Zelltod-bringt-antivirale-Immunantwort-in-Fahrt