Notes, news, and information on human and general molecular biology. My particular interests lie in immunology, cancer biology, pathology, and human evolution. I have a weakness for cute animal pictures.
I am psyched on these illustrations by Nicholas Beales! Coming from a microbiology and immunology background, I absolutely approved!
These are awesome! I’d love these as posters, they look like strange little warriors each pertaining to their own clan.
(via theolduvaigorge)
Helicobacter pylori (yellow), a common bacterium that lives in the stomach lining, increases the risk of stomach cancer (brown cells) and peptic ulcers. But over time H. pylori can reduce stomach acid and acid reflux, which may help fend off esophageal cancer. The microbe also appears to help protect us from allergies and asthma. Some scientists suspect that the dramatic increase in those conditions in the industrialized world could be related to the decreasing frequency of H. pylori in our stomachs, which is partly due to high doses of antibiotics in childhood.
Photograph by Martin Oeggerli, with support from School of Life Sciences, FHNW
(via Microbes: Small, Small World - Photo Gallery - Pictures, More From National Geographic Magazine)
(via fyeahmedlab)
Surveillance for Norovirus Outbreaks
“Noroviruses spread when people have contact with infected people, consume contaminated food or water, or touch contaminated objects. Outbreaks occur often and can happen to people of all ages in a variety of settings.”-CDC
Read on at: http://www.cdc.gov/features/dsNorovirus/
Helicobacter pylori
It’s a Gram Negative bacteria found in the stomach and it is responsible of many gastric ulcers and also of chronic gastritis.
Helicobacter pylori, a beautiful helical shaped “bug”, that moves like a helicopter, turning from here to there and punching holes in your stomach. - Lalo Mir (Silver Radio, 25/02/03)
Science that barks… do not bite!
(via fyeahmedlab)
BILLIONS of years ago, a tiny cyanobacterium cracked open a water molecule - and let loose a poison that wrought death and destruction on an epic scale. The microbe had just perfected photosynthesis, a process that freed the oxygen trapped inside water and killed early Earth’s anaerobic inhabitants.
Now, for the first time, geologists have found evidence of the crucial evolutionary stage just before cyanobacteria split water. The find offers a unique snapshot of the moment that made the modern world. With the advent of photosynthesis came an atmosphere dominated by oxygen and, ultimately, the diversity of life forms that we know today.
“This was the biggest change that ever occurred in the biosphere,” says Kevin Redding at Arizona State University in Tempe. “The extinction caused by oxygen was probably the largest ever seen, but at the same time animal life wouldn’t be possible without oxygen.”
Image source.
(via Captured: the moment photosynthesis changed the world)
(via theolduvaigorge)
A direct line through the brain to avoid rotten food
Consuming putrid food can be lethal as it allows bacterial pathogens to enter the digestive system. To detect signs of decay and thus allowing us and other animals to avoid such food poisoning is one of the main tasks of the sense of smell. Behavioural scientists and neurobiologists at the Max Planck Institute for Chemical Ecology in Jena, Germany, have now for the first time decoded the neural mechanisms underlying an escape reflex in fruit flies (Drosophila) activated in order to avoid eating and laying eggs in food infected by toxic microorganisms. A super-sensitive and completely dedicated neural line, from olfactory receptor, via sensory neuron and primary brain neurons, is activated as soon as the tiniest amount of geosmin is in the air. Geosmin is a substance released by bacteria and mold fungi toxic to the fly. This stimulus overrides all other food odour signals, irrespective of how attractive they are on their own. Consequently, geosmin is a full STOP signal that prevents flies from eating and laying eggs in toxic food, similar to when we open the fridge and smell last week’s forgotten dinner.
(via littlemicrobiologyblog)
(via bekindplzrewind)
Microbiology and art :) Yes, these are Petri dishes.
from ifuckinglovescience
Luke Jerram: Glass Microbiology
- T4-Bacteriophage
- Enterovirus 71 (EV71), one of the major causative agents for hand, foot and mouth disease (HFMD)
- H1N1 “Swine Flu” detail
- H5N1 “Avian Flu”
- E. coli
- Malaria
- Human Papillomavirus detail
These are just so cool.
(via fuckyeahnarcotics)
Harnessing Viruses
Viruses are skillful mutants, changing their structures or outer proteins to evade the shifting natural defences of their targets. That’s why you have to get a flu shot every year, and endure the seasonal week-long bout of the common cold (typically the fault of rhinoviruses). But scientists in France are looking at viruses in a significantly different light - they’re harnessing the power of one of viruses’ most proficient mutators, HIV, and using it to fight another intractable disease: Cancer.
A team of scientists at the French National Center for Scientific Research set out to study molecules that could improve the effectiveness of cancer drugs. This process often involves screening for desired traits using bacteria, but sometimes, a molecule that works one way in a bacterium will work totally differently in a human cell. The team realised that it would be far more efficient to both find new compounds and screen for them inside human cells - and to speed up the “finding” part of the process, they worked with HIV, taking advantage of both its replication machinery and high mutation rate.
As HIV replicates, it creates slightly new versions of itself over successive generations. This allows it to resist most of the drug cocktails and anti-viral treatments developed to fight it, but also makes it a powerful molecular tool: A mini factory that churns out new, subtly different compounds that work in slightly different ways. The CRNS team was interested in developing a more potent form of deoxycytidine kinase (dCK), a protein found in all cells that’s crucial for activating most anti-cancer drugs. The scientists hypothesised that if they could make a more potent form of dCK, the cancer drugs we have would work more effectively - causing lower required doses, minimised side effects, and less toxicity exposure for healthy cells.
“Mutant HIV”, complete with different takes on the dCK protein, were replicated through several generations, yielding an entire library; about 80 different mutants of dCK were isolated in total. Ultimately, they located a variant that induces tumour cells to die with just 1/300th the dose of cancer-killing drugs. There’s no doubt about it; this one-two protein punch is an effective tumour killer.
The discovery is notable for a few reasons - first, the mutated protein was shown to work in human cells; this is a massive deal, as a lot of the research we see published in the science sections of newspapers has had glowing success in animal trials, but hasn’t been tested in human cells yet. Second, it suggests weakening the tumour’s resistance to anti-cancer drugs could be instrumental in fighting and possibly curing the disease. Finally, it suggests a novel therapeutic use for one of humanity’s deadliest viruses - awesome.
It’s worth noting, though, that this technology certainly won’t be tumour-zapping in hospitals tomorrow: it’s got many more tests to go through before it gets to that stage. The “right-now” implications of this research are HIV’s use as a molecular factory for generating slightly mutated variants - which could have applications across a whole range of scientific fields.
Image, top: HIV-infected T-lymphocyte. Image, bottom: Dividing tumour cells.
The paper was originally published in PLoS Genetics. An article was also written in ScienceDaily about the subject.
Bacterial growth (Staphylococcus aureus) on Blood Agar Plate
(via arcticumsimiae)
H5N1 influenza virus: The answers
The scientific community is abuzz this week, following the publication of a second controversial H5N1 paper that identifies a series of mutations that give the virus the ability to spread through the air.
To bring you up to date on the current status of this potentially deadly virus, Ed Yong at Nature magazine has kindly presented the top five questions regarding H5N1, including:
- Why is it so successful?
- Where is it now?
- How does it kill?
- Will it become transmissible in humans?
- What else could cause a pandemic?
For the answers to these questions and more, head to Nature for the full article.
