ucsdhealthsciences
ucsdhealthsciences:

How Our Brains Store Recent Memories, Cell by Single CellFindings may shed light on how to treat neurological conditions like Alzheimer’s and epilepsy
Confirming what neurocomputational theorists have long suspected, researchers at the Dignity Health Barrow Neurological Institute in Phoenix, Ariz. and University of California, San Diego School of Medicine report that the human brain locks down episodic memories in the hippocampus, committing each recollection to a distinct, distributed fraction of individual cells.
The findings, published in the June 16 Early Edition of PNAS, further illuminate the neural basis of human memory and may, ultimately, shed light on new treatments for diseases and conditions that adversely affect it, such as Alzheimer’s disease and epilepsy.
“To really understand how the brain represents memory, we must understand how memory is represented by the fundamental computational units of the brain – single neurons – and their networks,” said Peter N. Steinmetz, MD, PhD, program director of neuroengineering at Barrow and senior author of the study. “Knowing the mechanism of memory storage and retrieval is a critical step in understanding how to better treat the dementing illnesses affecting our growing elderly population.”
Steinmetz, with first author John T. Wixted, PhD, Distinguished Professor of Psychology, Larry R. Squire, PhD, professor in the departments of neurosciences, psychiatry and psychology, both at UC San Diego, and colleagues, assessed nine patients with epilepsy whose brains had been implanted with electrodes to monitor seizures. The monitoring recorded activity at the level of single neurons.
The patients memorized a list of words on a computer screen, then viewed a second, longer list that contained those words and others. They were asked to identify words they had seen earlier, and to indicate how well they remembered them. The observed difference in the cell-firing activity between words seen on the first list and those not on the list clearly indicated that cells in the hippocampus were representing the patients’ memories of the words.
The researchers found that recently viewed words were stored in a distributed fashion throughout the hippocampus, with a small fraction of cells, about 2 percent, responding to any one word and a small fraction of words, about 3 percent, producing a strong change in firing in these cells.
"Intuitively, one might expect to find that any neuron that responds to one item from the list would also respond to the other items from the list, but our results did not look anything like that. The amazing thing about these counterintuitive findings is that they could not be more in line with what influential neurocomputational theorists long ago predicted must be true," said Wixted.
Although only a small fraction of cells coded recent memory for any one word, the scientists said the absolute number of cells coding memory for each word was large nonetheless – on the order of hundreds of thousands at least. Thus, the loss of any one cell, they noted, would have a negligible impact on a person’s ability to remember specific words recently seen.
Ultimately, the scientists said their goal is to fully understand how the human brain forms and represents memories of places and things in everyday life, which cells are involved and how those cells are affected by illness and disease. The researchers will next attempt to determine whether similar coding is involved in memories of pictures of people and landmarks and how hippocampal cells representing memory are impacted in patients with more severe forms of epilepsy.
Pictured: Human neuron showing actin formation in response to stimulation. Michael A. Colicos, UC San Diego

ucsdhealthsciences:

How Our Brains Store Recent Memories, Cell by Single Cell
Findings may shed light on how to treat neurological conditions like Alzheimer’s and epilepsy

Confirming what neurocomputational theorists have long suspected, researchers at the Dignity Health Barrow Neurological Institute in Phoenix, Ariz. and University of California, San Diego School of Medicine report that the human brain locks down episodic memories in the hippocampus, committing each recollection to a distinct, distributed fraction of individual cells.

The findings, published in the June 16 Early Edition of PNAS, further illuminate the neural basis of human memory and may, ultimately, shed light on new treatments for diseases and conditions that adversely affect it, such as Alzheimer’s disease and epilepsy.

“To really understand how the brain represents memory, we must understand how memory is represented by the fundamental computational units of the brain – single neurons – and their networks,” said Peter N. Steinmetz, MD, PhD, program director of neuroengineering at Barrow and senior author of the study. “Knowing the mechanism of memory storage and retrieval is a critical step in understanding how to better treat the dementing illnesses affecting our growing elderly population.”

Steinmetz, with first author John T. Wixted, PhD, Distinguished Professor of Psychology, Larry R. Squire, PhD, professor in the departments of neurosciences, psychiatry and psychology, both at UC San Diego, and colleagues, assessed nine patients with epilepsy whose brains had been implanted with electrodes to monitor seizures. The monitoring recorded activity at the level of single neurons.

The patients memorized a list of words on a computer screen, then viewed a second, longer list that contained those words and others. They were asked to identify words they had seen earlier, and to indicate how well they remembered them. The observed difference in the cell-firing activity between words seen on the first list and those not on the list clearly indicated that cells in the hippocampus were representing the patients’ memories of the words.

The researchers found that recently viewed words were stored in a distributed fashion throughout the hippocampus, with a small fraction of cells, about 2 percent, responding to any one word and a small fraction of words, about 3 percent, producing a strong change in firing in these cells.

"Intuitively, one might expect to find that any neuron that responds to one item from the list would also respond to the other items from the list, but our results did not look anything like that. The amazing thing about these counterintuitive findings is that they could not be more in line with what influential neurocomputational theorists long ago predicted must be true," said Wixted.

Although only a small fraction of cells coded recent memory for any one word, the scientists said the absolute number of cells coding memory for each word was large nonetheless – on the order of hundreds of thousands at least. Thus, the loss of any one cell, they noted, would have a negligible impact on a person’s ability to remember specific words recently seen.

Ultimately, the scientists said their goal is to fully understand how the human brain forms and represents memories of places and things in everyday life, which cells are involved and how those cells are affected by illness and disease. The researchers will next attempt to determine whether similar coding is involved in memories of pictures of people and landmarks and how hippocampal cells representing memory are impacted in patients with more severe forms of epilepsy.

Pictured: Human neuron showing actin formation in response to stimulation. Michael A. Colicos, UC San Diego

Whooping Cough Reaches Epidemic Proportions in California.
With more than 800 new cases reported in just the last two weeks, California has officially reached “epidemic proportions” of whooping cough (pertussis). Typically the state sees 80 to 100 cases a month. Babies are the most vulnerable.
As of June 10, there have been 3,458 cases reported to the California Department of Public Health (CDPH). That’s more than the number of reports for all of 2013, not to mention summer months are usually the worst. 
Two-thirds of pertussis hospitalizations have been in children four months or younger, and two infant deaths have already been reported. “We urge all pregnant women to get vaccinated,” CDPH director Ron Chapman says in a statement. “We also urge parents to vaccinate infants as soon as possible.” That also goes for anyone who expects to be around newborns.
The first dose of the pertussis vaccine can be given when an infant reaches 6 weeks of age. Infants who are too young to be immunized, however, remain the most vulnerable to severe and fatal cases. All pregnant women, the department urges, should be vaccinated with Tdap in their third trimester for each pregnancy — the immunity will transfer to the baby, at least temporarily. 
To be clear, whooping cough hasn’t been declared a public health emergency. When a disease exceeds anticipated levels, that’s when it’s considered an epidemic, according to CDPH’s Gil Chavez.Read the entire article here.Source: Los Angeles Times, I fucking love Science.

Whooping Cough Reaches Epidemic Proportions in California.

With more than 800 new cases reported in just the last two weeks, California has officially reached “epidemic proportions” of whooping cough (pertussis). Typically the state sees 80 to 100 cases a month. Babies are the most vulnerable.

As of June 10, there have been 3,458 cases reported to the California Department of Public Health (CDPH). That’s more than the number of reports for all of 2013, not to mention summer months are usually the worst. 

Two-thirds of pertussis hospitalizations have been in children four months or younger, and two infant deaths have already been reported. “We urge all pregnant women to get vaccinated,” CDPH director Ron Chapman says in a statement. “We also urge parents to vaccinate infants as soon as possible.” That also goes for anyone who expects to be around newborns.

The first dose of the pertussis vaccine can be given when an infant reaches 6 weeks of age. Infants who are too young to be immunized, however, remain the most vulnerable to severe and fatal cases. All pregnant women, the department urges, should be vaccinated with Tdap in their third trimester for each pregnancy — the immunity will transfer to the baby, at least temporarily. 

To be clear, whooping cough hasn’t been declared a public health emergency. When a disease exceeds anticipated levels, that’s when it’s considered an epidemic, according to CDPH’s Gil Chavez.

Read the entire article here.

Source: Los Angeles Times, I fucking love Science.

ucsdhealthsciences
ucsdhealthsciences:

Detecting Fetal Chromosomal Defects Without Risk Noninvasive sequencing is faster, cheaper and safer for mother and fetus, say researchers
Chromosomal abnormalities that result in birth defects and genetic disorders like Down syndrome remain a significant health burden in the United States and throughout the world, with some current prenatal screening procedures invasive and a potential risk to mother and unborn child.
In a paper published online this week in the Early Edition of PNAS, a team of scientists at the University of California, San Diego School of Medicine and in China describe a new benchtop semiconductor sequencing procedure and newly developed bioinformatics software tools that are fast, accurate, portable, less expensive and can be completed without harm to mother or fetus.  
“We believe this approach could become the standard of care for screening of prenatal chromosomal abnormalities,” said Kang Zhang, MD, PhD, professor of ophthalmology, founding director of the Institute for Genomic Medicine at UC San Diego and a staff physician at the San Diego VA Healthcare System.
The incidence of chromosomal abnormalities – in numbers or structure – is one in 160 live births in the United States, higher in other countries. In China, for example, the rate is one in 60 live births. The effects of these abnormalities, known as aneuploidies, can be severe, from developmental delays and neurological disorders to infertility and death. The incidence rate rises with maternal age, most notably after age 35.
Current diagnoses of fetal aneuploidies often rely upon invasive tests that sample amniotic fluid or placental tissues for fetal DNA that can then be analyzed using a variety of complex and expensive methods, including full karyotyping in which the entire set of chromosomes is viewed microscopically. While highly reliable, these invasive tests may cause infections in the pregnant woman and pose as much as a 1 percent risk of miscarriage and fetal loss. Results are not available for one to two weeks, extending anxiety for families waiting for information.
The new method relies upon massively parallel sequencing of cell-free fetal DNA using a benchtop semiconductor sequencing platform (SSP) called an Ion Torrent sequencer developed by Life Technologies. Cell-free fetal DNA is genetic material from the fetus that circulates naturally and freely in the mother’s bloodstream. It can be obtained through an ordinary blood draw, with SSP analysis achieved in less than four days.
To assess the SSP method, researchers tested 2,275 pregnant women. More than 500 participated in a retrospective analysis, undergoing full karyotyping to establish known chromosomal abnormalities followed by SSP testing. The remainder participated in a prospective study without prior karyotyping, and SSP testing results were then compared to karyotyping results. The sequencing and automated bioinformatics analyses were performed at iGenomics in Guangzhou, China.
“We used the retrospective study to establish the method and the prospective study to validate it,” said Zhang.
In the retrospective study, the researchers found that SSP detected multiple types of chromosomal abnormality with virtually 100 percent sensitivity and specificity compared to full karyotyping.
“To our knowledge, this is the first large-scale clinical study to systematically identify chromosomal aneuploidies based on cell-free fetal DNA using SSP,” said Zhang. “It provides an effective strategy for large-scale, noninvasive screenings in a clinical setting. It can be done in hospitals and outpatient clinics, more quickly and cheaply.”

ucsdhealthsciences:

Detecting Fetal Chromosomal Defects Without Risk
Noninvasive sequencing is faster, cheaper and safer for mother and fetus, say researchers

Chromosomal abnormalities that result in birth defects and genetic disorders like Down syndrome remain a significant health burden in the United States and throughout the world, with some current prenatal screening procedures invasive and a potential risk to mother and unborn child.

In a paper published online this week in the Early Edition of PNAS, a team of scientists at the University of California, San Diego School of Medicine and in China describe a new benchtop semiconductor sequencing procedure and newly developed bioinformatics software tools that are fast, accurate, portable, less expensive and can be completed without harm to mother or fetus.  

“We believe this approach could become the standard of care for screening of prenatal chromosomal abnormalities,” said Kang Zhang, MD, PhD, professor of ophthalmology, founding director of the Institute for Genomic Medicine at UC San Diego and a staff physician at the San Diego VA Healthcare System.

The incidence of chromosomal abnormalities – in numbers or structure – is one in 160 live births in the United States, higher in other countries. In China, for example, the rate is one in 60 live births. The effects of these abnormalities, known as aneuploidies, can be severe, from developmental delays and neurological disorders to infertility and death. The incidence rate rises with maternal age, most notably after age 35.

Current diagnoses of fetal aneuploidies often rely upon invasive tests that sample amniotic fluid or placental tissues for fetal DNA that can then be analyzed using a variety of complex and expensive methods, including full karyotyping in which the entire set of chromosomes is viewed microscopically. While highly reliable, these invasive tests may cause infections in the pregnant woman and pose as much as a 1 percent risk of miscarriage and fetal loss. Results are not available for one to two weeks, extending anxiety for families waiting for information.

The new method relies upon massively parallel sequencing of cell-free fetal DNA using a benchtop semiconductor sequencing platform (SSP) called an Ion Torrent sequencer developed by Life Technologies. Cell-free fetal DNA is genetic material from the fetus that circulates naturally and freely in the mother’s bloodstream. It can be obtained through an ordinary blood draw, with SSP analysis achieved in less than four days.

To assess the SSP method, researchers tested 2,275 pregnant women. More than 500 participated in a retrospective analysis, undergoing full karyotyping to establish known chromosomal abnormalities followed by SSP testing. The remainder participated in a prospective study without prior karyotyping, and SSP testing results were then compared to karyotyping results. The sequencing and automated bioinformatics analyses were performed at iGenomics in Guangzhou, China.

“We used the retrospective study to establish the method and the prospective study to validate it,” said Zhang.

In the retrospective study, the researchers found that SSP detected multiple types of chromosomal abnormality with virtually 100 percent sensitivity and specificity compared to full karyotyping.

“To our knowledge, this is the first large-scale clinical study to systematically identify chromosomal aneuploidies based on cell-free fetal DNA using SSP,” said Zhang. “It provides an effective strategy for large-scale, noninvasive screenings in a clinical setting. It can be done in hospitals and outpatient clinics, more quickly and cheaply.”

biomedicalephemera

Anonymous asked:

whats wrong with your cat?

biomedicalephemera answered:

I explain most of it at the link

Long story short, he’s got an abscessed tooth because of pre-existing terrible teeth (he was a street cat for a few years) that’s been getting reinfected and is eating farther into his nasal cavity, and needs to be removed before he becomes septic or gets in so much pain that he can’t eat.

He’s otherwise healthy (if a bit fat), so we really don’t want to lose him or force him to go through unnecessary pain for no reason.

Zarks is one of the few things we have left of my fiance’s mom, and in addition to our upcoming wedding, we also have my personal medical expenses (going onto a new insurance) coming up, so we’ve been put in a position where, if we have to cover everything ourselves, we’d be forced to put this surgery off to the point where it could very very easily devolve into a life-or-death situation.

OKAY. YEAH. Kitty sad and having infected tooth. Kitty has infected tooth because of previous life on the streets leading to cracked canine that, for the past 4 years, we’ve managed to keep uninfected. But now things are getting serious and we need some help. :( I’m the last person to ask anyone for help - I am so stupidly prideful that I give up incredibly important things just so that I don’t have to ask for help. But even doing that, we don’t have enough for this surgery and his follow-up care.

Read more at the actual site

image

Zarkster loves you! Help him out <3 

Most of you guys know Arallyn, the lovely lady that runs biomedicalephemera

Well, she’s my friend, and she needs your help. If you can, donate to help her out with veterinary expenses for her cat Zarky! If not, that’s okay! You can always reblog this and signal boost. Everything helps!

She also has a really cool giveaway going on…check it out! She’s awesome.

pestilense

txchnologist:

Smart Solution To Stop Needle Reuse Wins Design Impact Award

Healthcare providers reusing unsterilized syringes and needles cause more than 1.3 million infections around the world every year, according to the World Health Organization. Ignorance of the dangers and a lack of supplies means that the average syringe is reused four times in the developing world, says advocacy and education charity Safepoint

The problem, which spreads bloodborne pathogens like hepatitis and AIDS HIV (h/t and good catch to sexeducationforprudes), led healthcare designer David Swann and his team at the University of Huddersfield in the United Kingdom to come up with a simple and cheap visual aid. 

They created a syringe coated with a color-changing dye that turns red when exposed to carbon dioxide. The so-called A Behavior-Changing (ABC) syringe is stored in a nitrogen-filled pack and starts changing color only when the pack is punctured or the syringe is removed. Read more below and see the video.

Read More

biomedicalephemera
biomedicalephemera:

Important People of Medicine: Virginia Apgar
If you’ve ever had, or been around a baby that was born in a hospital, Dr. Apgar’s name probably sounds familiar. An anesthesiologist and teratologist (one who studies abnormalities of physical development), Virginia Apgar is most well-known for the "Apgar score" - a rating given to infants at 1 and 5 minutes after birth, which is often a determining factor in whether or not the baby needs to remain in the hospital after birth.
Dr. Apgar was the first female doctor to receive professorship at Columbia University medical school, and her work in teratology during the rubella pandemic of 1964-65 led to her outspoken advocacy for universal vaccination against that disease. Though it’s often mild and annoying above all else in healthy people, when pregnant women contract rubella (also known as German measles), the rate of deformity and disability of their children skyrockets. It can even cause miscarriage.
Virginia Apgar also promoted universal Rh-testing among pregnant women. This test shows whether a woman has a different Rh blood type than her fetus, because if she does, she can develop antibodies that can cross the placenta and destroy fetal blood cells. This can cause fetal hydrops and high levels of neonatal mortality, but can be prevented by administering anti-RhD IgG injections to the mother during pregnancy, so that she does not develop a sensitivity (and subsequent antibodies) to her baby’s blood type.
Though Dr. Apgar never married or had children of her own, she saved the lives of countless babies and streamlined many medical considerations of neonatal care, resulting in more effective medical treatment. She studied and promoted the prevention of premature births and causes of fetal deformity. She worked for March of Dimes and taught thousands of students. Her influence in the obstetrics and neonatology fields cannot be overstated.

biomedicalephemera:

Important People of Medicine: Virginia Apgar

If you’ve ever had, or been around a baby that was born in a hospital, Dr. Apgar’s name probably sounds familiar. An anesthesiologist and teratologist (one who studies abnormalities of physical development), Virginia Apgar is most well-known for the "Apgar score" - a rating given to infants at 1 and 5 minutes after birth, which is often a determining factor in whether or not the baby needs to remain in the hospital after birth.

Dr. Apgar was the first female doctor to receive professorship at Columbia University medical school, and her work in teratology during the rubella pandemic of 1964-65 led to her outspoken advocacy for universal vaccination against that disease. Though it’s often mild and annoying above all else in healthy people, when pregnant women contract rubella (also known as German measles), the rate of deformity and disability of their children skyrockets. It can even cause miscarriage.

Virginia Apgar also promoted universal Rh-testing among pregnant women. This test shows whether a woman has a different Rh blood type than her fetus, because if she does, she can develop antibodies that can cross the placenta and destroy fetal blood cells. This can cause fetal hydrops and high levels of neonatal mortality, but can be prevented by administering anti-RhD IgG injections to the mother during pregnancy, so that she does not develop a sensitivity (and subsequent antibodies) to her baby’s blood type.

Though Dr. Apgar never married or had children of her own, she saved the lives of countless babies and streamlined many medical considerations of neonatal care, resulting in more effective medical treatment. She studied and promoted the prevention of premature births and causes of fetal deformity. She worked for March of Dimes and taught thousands of students. Her influence in the obstetrics and neonatology fields cannot be overstated.