medicalschool

medicalschool:

In the past few years, next-generation cancer drugs have started trickling into the clinics, including a smart inhibitor that block a specific mutant kinase (V600E-B-RAF) and antibodies that can induce T cell-mediated rejection of certain tumors (anti-CTL4 antibodies). Another promising approach is to genetically modify T cells to attack tumors and then infuse the cells into cancer patients. Indeed, this strategy is currently entering clinical trials, specifically with T cells engineered to express the chimeric antigen receptors (CARs).

Movie: Here T cells (gray) are engineered to express chimeric antigen receptors (CARs) to redirect T-cell specificity to target CD19-positive tumor cells, expressing EGFP (green). Tumor cells turn red after the T-cell attacks and kills them (propidium iodide staining). The time-lapse imaging was performed using Nikon’s BioStation. Video presented by Alex’s Lemonade Stand Foundation.

labphoto
labphoto:

Doing experiments with an aerobic oxidation using a copper-amine complex as a catalyst. 
The 7 colorful solution in the vials are reaction mixtures with the same reactants in different solvents (methanol, ethanol, propanol, acetonitrile, ethyl-acetate, diemthylformamide, dimethylsulfoxide, ect.). Here I would like to know that which solvents could be used for this oxidation. 
Luckily in 40% of the solvents, something happened.

labphoto:

Doing experiments with an aerobic oxidation using a copper-amine complex as a catalyst. 

The 7 colorful solution in the vials are reaction mixtures with the same reactants in different solvents (methanol, ethanol, propanol, acetonitrile, ethyl-acetate, diemthylformamide, dimethylsulfoxide, ect.). Here I would like to know that which solvents could be used for this oxidation. 

Luckily in 40% of the solvents, something happened.

neurosciencestuff
neurosciencestuff:

Research Shows How Brain Can Tell Magnitude of Errors 
University of Pennsylvania researchers have made another advance in understanding how the brain detects errors caused by unexpected sensory events. This type of error detection is what allows the brain to learn from its mistakes, which is critical for improving fine motor control.  
Their previous work explained how the brain can distinguish true error signals from noise; their new findings show how it can tell the difference between errors of different magnitudes. Fine-tuning a tennis serve, for example, requires that the brain distinguish whether it needs to make a minor correction if the ball barely misses the target or a much bigger correction if it is way off.
The study was led by Javier Medina, an assistant professor in the Department of Psychology in Penn’s School of Arts & Sciences, and Farzaneh Najafi, then a graduate student in the Department of Biology. They collaborated with postdoctoral fellow Andrea Giovannucci and associate professor Samuel S. H. Wang of Princeton University.
It was published in the journal eLife.
Our movements are controlled by neurons known as Purkinje cells. Each muscle receives instructions from a dedicated set of hundreds of these brain cells. The instructions sent by each set of Purkinje cells are constantly fine tuned by climbing fibers, a specialized group of neurons that alert Purkinje cells whenever an unexpected stimulus occurs.
“An unexpected stimulus is often a sign that something has gone wrong,” Medina said, “When this happens, climbing fibers send signals to their related Purkinje cells that an error has occurred. These Purkinje cells can then make changes to avoid the error in the future.”
These error signals are mixed in with random firings of the climbing fibers, however, and researchers were long mystified about how the brain tells the difference between this noise and the useful, error-related information it needs to improve motor control.
Medina and his team showed the mechanism behind this differentiation in a study published earlier this year. By using a non-invasive microscopy technique that could monitor the Purkinje cells of awake and active mice, the researchers could measure the level of calcium within these cells when they received signals from climbing fibers.
The unexpected stimuli in this experiment were random puffs of air to the face, which caused the mice to blink. The researchers located Purkinje cells that control the mice’s eyelids and saw that calcium levels necessary for neuroplasticity, i.e., the brain’s ability to learn, were greater when the mice got an error signal triggered by a puff of air than they were after a random signal.
While being able to make such a distinction is critical to the brain’s ability to improve motor control, more information is needed to fine-tune it.  
“We wanted to see if the Purkinje cells could tell the difference not just between random firings and true errors signals but between smaller and bigger errors,” Medina said.
In their new study, the researchers used the same experimental set-up, with one key difference. They used air puffs of different durations: 15 milliseconds and 30 milliseconds.
What they found was that the eyelid-associated Purkinje cells filled with different amounts of calcium depending on the length of the puff; the longer ones produced larger spikes in calcium levels.        
In addition, the researchers saw that different percentages of eyelid-related Purkinje cells respond depending on the length of the puff.  
“Though there is a large population of climbing fibers that can give error-related information to the relevant Purkinje cells when they encounter something unexpected, not all of them fire each time,” Medina said. “We saw that there is information coded in the number of climbing fibers that fire. The longer puffs corresponded to more climbing fibers sending signals to their Purkinje cells.”
Their study could help explain how practice makes perfect, even when errors are imperceptibly small.
“If you felt a short puff and a long puff, you might not be able to say which one was which, but Purkinje cells can tell the difference,” Medina said. “The difference between a ‘very good’ and an ‘awesome’ tennis serve rests on being able to distinguish errors even as tiny as that.” 

neurosciencestuff:

Research Shows How Brain Can Tell Magnitude of Errors

University of Pennsylvania researchers have made another advance in understanding how the brain detects errors caused by unexpected sensory events. This type of error detection is what allows the brain to learn from its mistakes, which is critical for improving fine motor control.  

Their previous work explained how the brain can distinguish true error signals from noise; their new findings show how it can tell the difference between errors of different magnitudes. Fine-tuning a tennis serve, for example, requires that the brain distinguish whether it needs to make a minor correction if the ball barely misses the target or a much bigger correction if it is way off.

The study was led by Javier Medina, an assistant professor in the Department of Psychology in Penn’s School of Arts & Sciences, and Farzaneh Najafi, then a graduate student in the Department of Biology. They collaborated with postdoctoral fellow Andrea Giovannucci and associate professor Samuel S. H. Wang of Princeton University.

It was published in the journal eLife.

Our movements are controlled by neurons known as Purkinje cells. Each muscle receives instructions from a dedicated set of hundreds of these brain cells. The instructions sent by each set of Purkinje cells are constantly fine tuned by climbing fibers, a specialized group of neurons that alert Purkinje cells whenever an unexpected stimulus occurs.

“An unexpected stimulus is often a sign that something has gone wrong,” Medina said, “When this happens, climbing fibers send signals to their related Purkinje cells that an error has occurred. These Purkinje cells can then make changes to avoid the error in the future.”

These error signals are mixed in with random firings of the climbing fibers, however, and researchers were long mystified about how the brain tells the difference between this noise and the useful, error-related information it needs to improve motor control.

Medina and his team showed the mechanism behind this differentiation in a study published earlier this year. By using a non-invasive microscopy technique that could monitor the Purkinje cells of awake and active mice, the researchers could measure the level of calcium within these cells when they received signals from climbing fibers.

The unexpected stimuli in this experiment were random puffs of air to the face, which caused the mice to blink. The researchers located Purkinje cells that control the mice’s eyelids and saw that calcium levels necessary for neuroplasticity, i.e., the brain’s ability to learn, were greater when the mice got an error signal triggered by a puff of air than they were after a random signal.

While being able to make such a distinction is critical to the brain’s ability to improve motor control, more information is needed to fine-tune it.  

“We wanted to see if the Purkinje cells could tell the difference not just between random firings and true errors signals but between smaller and bigger errors,” Medina said.

In their new study, the researchers used the same experimental set-up, with one key difference. They used air puffs of different durations: 15 milliseconds and 30 milliseconds.

What they found was that the eyelid-associated Purkinje cells filled with different amounts of calcium depending on the length of the puff; the longer ones produced larger spikes in calcium levels.        

In addition, the researchers saw that different percentages of eyelid-related Purkinje cells respond depending on the length of the puff.  

“Though there is a large population of climbing fibers that can give error-related information to the relevant Purkinje cells when they encounter something unexpected, not all of them fire each time,” Medina said. “We saw that there is information coded in the number of climbing fibers that fire. The longer puffs corresponded to more climbing fibers sending signals to their Purkinje cells.”

Their study could help explain how practice makes perfect, even when errors are imperceptibly small.

“If you felt a short puff and a long puff, you might not be able to say which one was which, but Purkinje cells can tell the difference,” Medina said. “The difference between a ‘very good’ and an ‘awesome’ tennis serve rests on being able to distinguish errors even as tiny as that.” 

neurosciencenews
neurosciencenews:

Scientists Discover Neurochemical Imbalance in Schizophrenia
Read the full article Scientists Discover Neurochemical Imbalance in Schizophrenia at NeuroscienceNews.com.
Using human induced pluripotent stem cells (hiPSCs), researchers at Skaggs School of Pharmacy and Pharmaceutical Sciences at University of California, San Diego have discovered that neurons from patients with schizophrenia secrete higher amounts of three neurotransmitters broadly implicated in a range of psychiatric disorders.
The research is in Stem Cell Reports. (full open access)
Research: “Human iPSC Neurons Display Activity-Dependent Neurotransmitter Secretion: Aberrant Catecholamine Levels in Schizophrenia Neurons ” by Vivian Hook, Kristen J. Brennand, Yongsung Kim, Thomas Toneff, Lydiane Funkelstein, Kelly C. Lee, Michael Ziegler, and Fred H. Gage in Stem Cell Reports. doi:10.1016/j.stemcr.2014.08.001 (http://www.sciencedirect.com/science/article/pii/S2213671114002458)
Image: This image shows enzymes that biosynthesize the neurotransmitters: Dopamine (left), norepinephrine (center) and epinephrine (right). Credit UCSD School of Medicine.

neurosciencenews:

Scientists Discover Neurochemical Imbalance in Schizophrenia

Read the full article Scientists Discover Neurochemical Imbalance in Schizophrenia at NeuroscienceNews.com.

Using human induced pluripotent stem cells (hiPSCs), researchers at Skaggs School of Pharmacy and Pharmaceutical Sciences at University of California, San Diego have discovered that neurons from patients with schizophrenia secrete higher amounts of three neurotransmitters broadly implicated in a range of psychiatric disorders.

The research is in Stem Cell Reports. (full open access)

Research: “Human iPSC Neurons Display Activity-Dependent Neurotransmitter Secretion: Aberrant Catecholamine Levels in Schizophrenia Neurons ” by Vivian Hook, Kristen J. Brennand, Yongsung Kim, Thomas Toneff, Lydiane Funkelstein, Kelly C. Lee, Michael Ziegler, and Fred H. Gage in Stem Cell Reports. doi:10.1016/j.stemcr.2014.08.001 (http://www.sciencedirect.com/science/article/pii/S2213671114002458)

Image: This image shows enzymes that biosynthesize the neurotransmitters: Dopamine (left), norepinephrine (center) and epinephrine (right). Credit UCSD School of Medicine.

medresearch
medresearch:

Investigating the Deadly Potential of a Common Fungus
Fungal spores are everywhere—in your garden, probably in your carpet, and even in the air. For most people this is not a problem. But for those with a weakened immune system, such as people undergoing chemotherapy or recipients of an organ transplant, exposure to certain fungi can be dangerous. One of the chief troublemakers, Aspergillus fumigatus, can be deadly when it invades the lungs or other organs. Robert Cramer, PhD, an assistant professor of microbiology and immunology at Dartmouth’s Geisel School of Medicine, wants to know why invasive A. fumigatus is so virulent.
“In general, fungi do not grow well at human body temperature,” explains Cramer. “Yet there is something about the biology of this organism that allows it to do very well in a human host who has a weakened immune system, and we just don’t know what that is.”
Read more
Care about research like this? Sign on to our Thunderclap campaign (http://bit.ly/NIHthunderclap) to tell Congress to finish what it started and pass the FY 2015 Labor-HHS spending bill now to restore sequestration cuts so that the promise of National Institutes of Health (NIH)-sponsored research can be realized.

medresearch:

Investigating the Deadly Potential of a Common Fungus

Fungal spores are everywhere—in your garden, probably in your carpet, and even in the air. For most people this is not a problem. But for those with a weakened immune system, such as people undergoing chemotherapy or recipients of an organ transplant, exposure to certain fungi can be dangerous. One of the chief troublemakers, Aspergillus fumigatus, can be deadly when it invades the lungs or other organs. Robert Cramer, PhD, an assistant professor of microbiology and immunology at Dartmouth’s Geisel School of Medicine, wants to know why invasive A. fumigatus is so virulent.

“In general, fungi do not grow well at human body temperature,” explains Cramer. “Yet there is something about the biology of this organism that allows it to do very well in a human host who has a weakened immune system, and we just don’t know what that is.”

Read more

Care about research like this? Sign on to our Thunderclap campaign (http://bit.ly/NIHthunderclap) to tell Congress to finish what it started and pass the FY 2015 Labor-HHS spending bill now to restore sequestration cuts so that the promise of National Institutes of Health (NIH)-sponsored research can be realized.

science-junkie

projectionsonthewall:

Neil deGrasse Tyson on Aliens

Hawking is all worried that aliens might suck our brains out. That concern comes from the fact that when any of us explored the world with high technology ships and came upon a civilization less advanced, it was bad for the less advanced civilization. They either were completely wiped out or subjugated or enslaved or whatever, so I think his fear about aliens is a reflection of his actual knowledge of how humans treat each other, not real knowledge of how real aliens would treat us."

- Neil deGrasse Tyson