Paraphyletic

Medicine and human biology
Proton pump inhibitors (like PrevAcid and Prilosec) are the third-most used drug in the United States, accounting for billions of dollars in sales every year.
And they’ve been a lifesaver for a lot of us, particularly those in their mid 20s and older who are hit hard by acid reflux disease. We love coffee, we love pizza, fruit juice, cake, etc., but these foods can mean pain and lost sleep for people who respond by making too much acid.
Over the last few years, there’ve been dozens of reports, mostly based on correlative studies, that PPIs may be bad for some people. PPI use has been associated with calcium loss, heart attack, and irregular platelet count.
This week in Circulation, doctors at my hospital, Stanford Medical School, and Imperial College London report that PPIs interfere with a crucial chemical signal pathway that eventually leads to tightened blood vessels that never fully relax (in mice, but the chemical response was confirmed in human tissue culture).
A large-scale study of the general human population is needed to know for sure whether PPIs are dangerous, even to people who are active and healthy. But as a user of PPIs myself, I’ll admit I’m troubled.

Proton pump inhibitors (like PrevAcid and Prilosec) are the third-most used drug in the United States, accounting for billions of dollars in sales every year.

And they’ve been a lifesaver for a lot of us, particularly those in their mid 20s and older who are hit hard by acid reflux disease. We love coffee, we love pizza, fruit juice, cake, etc., but these foods can mean pain and lost sleep for people who respond by making too much acid.

Over the last few years, there’ve been dozens of reports, mostly based on correlative studies, that PPIs may be bad for some people. PPI use has been associated with calcium loss, heart attack, and irregular platelet count.

This week in Circulation, doctors at my hospital, Stanford Medical School, and Imperial College London report that PPIs interfere with a crucial chemical signal pathway that eventually leads to tightened blood vessels that never fully relax (in mice, but the chemical response was confirmed in human tissue culture).

A large-scale study of the general human population is needed to know for sure whether PPIs are dangerous, even to people who are active and healthy. But as a user of PPIs myself, I’ll admit I’m troubled.

i-heart-histo:

The Seamless Gut by i-heart-histo

Each region of your digestive tract is histologically different.

Specialized in its own unique way to impart a specific function. When the different regions of these tubes work together they function as a seamless system that protects, absorbs and secretes. Ensuring that we digest the products we ingest, remove the nutrients that we need and dispose of those that we don’t.

Students of histology frequently meditate on the differences between these regions in an attempt to correlate structure with function and categorize regions based on appearance.

The seamless gut tube demonstrates these differences in a single image allowing junior histologists to compare and marvel in the functional specializations of each region.

1. Esophagus (middle third)

Non-keratinized stratified squamous epithelium provides protection against the abrasive forces encountered as the bolus is transmitted toward the stomach.

A muscularis externa composed of a unique smooth and skeletal muscle mix.

2. Stomach (fundus)

Large folds of mucosa and submucosa form rugae, which allow the stomach to distend as it fills with food.

Glandular epithelium composed of gastric pits opening into deep gastric glands. These contain numerous cells each with their own role to play in the digestion process through secretion of either hydrochloric acid, pepsinogen, mucous or hormones.

3. Duodenum

The mucosa becomes heavily folded to form villi, finger-like projections that increase the surface area across which absorption can occur.

Each simple columnar epithelial cell has a highly folded apical membrane forming microvilli, which still further increase the surface area for absorption.

The distinctive Brunner’s glands in the submucosa release a bicarbonate rich secretion into the duodenal lumen to neutralize the acidic contents released from the stomach and help prevent formation of a duodenal ulcer.

4. Jejunum

Villi, microvilli and plicae circulares (circular folds of the mucosa) are evident in the jejunum. It lacks any submucosal features which makes it easy to distinguish from duodenum and ileum.

5. Ileum

The final section of the small intestine also contains villi and epithelial cells with microvilli.

Large lymphoid aggregates known as Peyer’s patches reside in the submucosa, breach into the lamina propria and making this a clear feature of ileum.

6. Appendix

Surrounded by lymphoid nodules (similar to the ileum) but this vestigial region of gut tube has no villi or microvilli. Instead its mucosa contains deep crypts of Lieberkuhn lined by goblet cells that secret mucous.

7. Colon

Distinctive because of its large crypts of Lieberkuhn lined by goblet cells that produce large volumes of mucous. The mucous facilitates the passage of feces which become increasingly drier as more water is absorbed from them as they pass through the large intestine.

The muscularis mucosa has a distinctive arrangement in the colon also. The outer longitudinal layer of muscle no longer forms a sheet of smooth muscle around the tube, but is organized into three thin, evenly spaced bands called teniae coli.

Something to think about the next time you take a bite of your sandwich?

i-heart-histo

(Source: i-heart-histo)

neurosciencestuff:

A Deep Brain Disorder
An SDSU research team has discovered that autism in children affects not only social abilities, but also a broad range of sensory and motor skills.

A group of investigators from San Diego State University’s Brain Development Imaging Laboratory are shedding a new light on the effects of autism on the brain.
The team has identified that connectivity between the thalamus, a deep brain structure crucial for sensory and motor functions, and the cerebral cortex, the brain’s outer layer, is impaired in children with autism spectrum disorders (ASD).
Led by Aarti Nair, a student in the SDSU/UCSD Joint Doctoral Program in Clinical Psychology, the study is the first of its kind, combining functional and anatomical magnetic resonance imaging (fMRI) techniques and diffusion tensor imaging (DTI) to examine connections between the cerebral cortex and the thalamus.
Nair and Dr. Ralph-Axel Müller, an SDSU professor of psychology who was senior investigator of the study, examined more than 50 children, both with autism and without.
Brain communication
The thalamus is a crucial brain structure for many functions, such as vision, hearing, movement control and attention. In the children with autism, the pathways connecting the cerebral cortex and thalamus were found to be affected, indicating that these two parts of the brain do not communicate well with each other.
“This impaired connectivity suggests that autism is not simply a disorder of social and communicative abilities, but also affects a broad range of sensory and motor systems,” Müller said.
Disturbances in the development of both the structure and function of the thalamus may play a role in the emergence of social and communicative impairments, which are among the most prominent and distressing symptoms of autism.
While the findings reported in this study are novel, they are consistent with growing evidence on sensory and motor abnormalities in autism. They suggest that the diagnostic criteria for autism, which emphasize social and communicative impairment, may fail to consider the broad spectrum of problems children with autism experience.
The study was supported with funding from the National Institutes of Health and additional funding from Autism Speaks Dennis Weatherstone Predoctoral Fellowship. It was published in the June issue of the journal, BRAIN.

neurosciencestuff:

A Deep Brain Disorder

An SDSU research team has discovered that autism in children affects not only social abilities, but also a broad range of sensory and motor skills.

A group of investigators from San Diego State University’s Brain Development Imaging Laboratory are shedding a new light on the effects of autism on the brain.

The team has identified that connectivity between the thalamus, a deep brain structure crucial for sensory and motor functions, and the cerebral cortex, the brain’s outer layer, is impaired in children with autism spectrum disorders (ASD).

Led by Aarti Nair, a student in the SDSU/UCSD Joint Doctoral Program in Clinical Psychology, the study is the first of its kind, combining functional and anatomical magnetic resonance imaging (fMRI) techniques and diffusion tensor imaging (DTI) to examine connections between the cerebral cortex and the thalamus.

Nair and Dr. Ralph-Axel Müller, an SDSU professor of psychology who was senior investigator of the study, examined more than 50 children, both with autism and without.

Brain communication

The thalamus is a crucial brain structure for many functions, such as vision, hearing, movement control and attention. In the children with autism, the pathways connecting the cerebral cortex and thalamus were found to be affected, indicating that these two parts of the brain do not communicate well with each other.

“This impaired connectivity suggests that autism is not simply a disorder of social and communicative abilities, but also affects a broad range of sensory and motor systems,” Müller said.

Disturbances in the development of both the structure and function of the thalamus may play a role in the emergence of social and communicative impairments, which are among the most prominent and distressing symptoms of autism.

While the findings reported in this study are novel, they are consistent with growing evidence on sensory and motor abnormalities in autism. They suggest that the diagnostic criteria for autism, which emphasize social and communicative impairment, may fail to consider the broad spectrum of problems children with autism experience.

The study was supported with funding from the National Institutes of Health and additional funding from Autism Speaks Dennis Weatherstone Predoctoral Fellowship. It was published in the June issue of the journal, BRAIN.

ucsfbioengineering:

What is precision medicine? Learn how the world’s thinkers, creators and innovators are taking action on new approaches and projects that will harness the wealth of information from genetics and health records to transform medicine worldwide.

medicalschool:

In the hippocampus, neural stem cells (green) sit in a layer below their progeny, the granule neurons (red). When activated by extrinsic stimuli, they enter mitosis and generate neuron progenitor cells, which eventually mature into neurons and migrate into the layer above. The number of neural stem cells in the hippocampus decreases over time, possibly contributing to the cognitive impairment associated with aging. One hypothesis is that, after a rapid series of divisions, these neural stem cells disappear via their conversion into astrocytes.
Image: Section of a mouse hippocampus imaged with Zeiss LSM 50 confocal microscope with a 40X C-Apochromat water-immersion objective lens (N.A. value 1.2, working distance 220 microns) at 62x magnification. Brain slices were fixed in 4% paraformaldehyde, immunolabeled, and then cleared in FocusClear (CelExplorer, Taiwan).

medicalschool:

In the hippocampus, neural stem cells (green) sit in a layer below their progeny, the granule neurons (red). When activated by extrinsic stimuli, they enter mitosis and generate neuron progenitor cells, which eventually mature into neurons and migrate into the layer above. The number of neural stem cells in the hippocampus decreases over time, possibly contributing to the cognitive impairment associated with aging. One hypothesis is that, after a rapid series of divisions, these neural stem cells disappear via their conversion into astrocytes.

Image: Section of a mouse hippocampus imaged with Zeiss LSM 50 confocal microscope with a 40X C-Apochromat water-immersion objective lens (N.A. value 1.2, working distance 220 microns) at 62x magnification. Brain slices were fixed in 4% paraformaldehyde, immunolabeled, and then cleared in FocusClear (CelExplorer, Taiwan).

(via diamidinophenylindolee)

Zheng Yin, Stephen T.C. Wong, Chris Bakal et al

Changes in cell shape may lead to metastasis, not the other way around
A crucial step toward skin cancer may be changes in the genes that control cell shape, report a team of scientists from The Methodist Hospital Research Institute, the Institute of Cancer Research, London, and Harvard Medical School in an upcoming issue of Nature Cell Biology (now online)…
Their work could lead to a better understanding of how cells become metastatic and, eventually, pinpoint new gene therapy targets for cancer treatment.
More here

Zheng Yin, Stephen T.C. Wong, Chris Bakal et al

Changes in cell shape may lead to metastasis, not the other way around

A crucial step toward skin cancer may be changes in the genes that control cell shape, report a team of scientists from The Methodist Hospital Research Institute, the Institute of Cancer Research, London, and Harvard Medical School in an upcoming issue of Nature Cell Biology (now online)…

Their work could lead to a better understanding of how cells become metastatic and, eventually, pinpoint new gene therapy targets for cancer treatment.

More here


They’re pretty, but are killing your feet
… The X-ray is a prop that Liebow says he shows to patients who “walk into the office in six-inch heels and say, ‘My feet are killing me! Why?’ ” He says he tells them, “That is not how your foot has evolved to walk.”
To sum up his brief and frequently futile plea for foot health: Humans are meant to walk heel-to-toe, with the leg at about a 90-degree angle to the foot and the ankle joint employing a 60-degree range of motion during normal daily activities. By wearing a high heel, Liebow explains, “you’re altering the position of the foot and how the foot is to function. Therefore, lots of bad things happen” (Washington Post)

Stilettos aren’t only murder on your feet.
They can do quite a number on faces.

They’re pretty, but are killing your feet

… The X-ray is a prop that Liebow says he shows to patients who “walk into the office in six-inch heels and say, ‘My feet are killing me! Why?’ ” He says he tells them, “That is not how your foot has evolved to walk.”

To sum up his brief and frequently futile plea for foot health: Humans are meant to walk heel-to-toe, with the leg at about a 90-degree angle to the foot and the ankle joint employing a 60-degree range of motion during normal daily activities. By wearing a high heel, Liebow explains, “you’re altering the position of the foot and how the foot is to function. Therefore, lots of bad things happen” (Washington Post)

Stilettos aren’t only murder on your feet.

They can do quite a number on faces.

talesofdrunkennessandcruelty:

What Makes Tattoos Permanent?
It’s all about the particles in the tattoo ink’s pigment says Dr. Anne Laumann, MBChB, a professor of dermatology at Northwestern University.
Tattoo application uses a mechanized needle to puncture the skin and inject ink into the dermis or second layer of skin just below the epidermis. Since the process involves damaging the skin, the body responds with white blood cells which attempt to absorb the foreign particles and dispose of them in the blood stream.
“The reason pigment stays there is because the pigment particles are too big to be eaten by the white cells, so they just sit there,” Laumann says.

talesofdrunkennessandcruelty:

What Makes Tattoos Permanent?

It’s all about the particles in the tattoo ink’s pigment says Dr. Anne Laumann, MBChB, a professor of dermatology at Northwestern University.

Tattoo application uses a mechanized needle to puncture the skin and inject ink into the dermis or second layer of skin just below the epidermis. Since the process involves damaging the skin, the body responds with white blood cells which attempt to absorb the foreign particles and dispose of them in the blood stream.

“The reason pigment stays there is because the pigment particles are too big to be eaten by the white cells, so they just sit there,” Laumann says.