Endochondral Ossification:  Most bones begin as hyaline cartilage and are converted to bones through endochondral ossification.

• Chondrocytes, cartilage cells, in the center of bone begin to enlarge, causing the cartilage itself to increase in size.  As this occurs, the matrix begins to calcify thwarting diffusion of nutrients through the calcified cartilage.  As a result, the chondrocytes die and disintegrate due to the lack of nourishment.

• Soon blood vessels grow and spread around the edges of the cartilage, also known as perichondrium.  This results in the cells within perichondrium to differentiate into osteoblasts which work to create a thin layer of bone around the shaft.  Osteoblasts are responsible for manufacturing and releasing the organic and protein components of bone matrix.  The perichondrium then turns into periosteum since it has transformed from cartilage to bone.  Periosteum is a fibrous outer layer and a cellular inner layer which wraps around the bone.

• The increase in activity in the periosteum causes blood supply to increase.  Soon the capillaries and fibroblasts invade the center of the cartilage causing the calcified matrix (in the center) to break down.  The fibroblasts also specialize to form osteoblasts which turn the matrix into spongy bone.  The center where all this is taking place is known as the primary ossification center which soon spreads outward.

• As the bone continues to grown, marrow cavity is formed through the process of remodeling.  The osteoclasts secrete acids and proteolytic enzymes to dissolve the matrix, resulting in the formation of marrow cavity.  The bone grows both in length and in width.

• Soon secondary ossification center forms as the ends of the bones which become calcified.  The capillaries and osteoblasts migrate into the center of the epiphyses, ends of the bones.  The same process that occurred at the primary ossification center occurs in the epiphyses.

• The epiphysis is occupied with spongy bone; however, some of the original cartilage remains exposed to the joint cavity called articular cartilage.  The articular cartilage thwarts damage to bones when they are in contact.  The epiphysis  is separated from the diaphysis (shaft of the bone) by epiphyseal cartilage or epiphyseal plate.  The epiphyseal plate is usually located at the metaphysis (where epiphysis and diaphysis come together).

Intramembranous Ossification:  This process occurs when osteoblasts differentiate within mesenchymal or fibrous connective tissue to form bones.

• Mesenchymal cells start the process of ossification as they gather together and produce organic components of matrix, resulting in mineralization of the osteoid (tissue which turns into bone).  These mesenchymal cells then differentiate to form osteoblasts while calcification takes place.  Calcification is the process of depositing calcium or calcium salts.  The bone then grows out from the ossification center in spicules which are small struts.  Some of the osteoblasts become trapped in the process of ossification, forming osteocytes.

• In order for the bones to continue growing and for the cells to stay alive, they require oxygen and nutrients.  As a result, the fusing of spicules traps some of the blood vessels within the bone.

• At first, the bone is composed of only spongy bone.  However, through remodeling, compact bone and marrow cavity could be formed.

Related posts:

1. Alcor Life Preservation via Cryonics

A synthetic version of the camouflage mechanism could be injected into the patients, which would teach our immune system to identify HIV and neutralize it.  This idea has been devised into a candidate vaccine and is being evaluated in animals and possibly in humans within two years.  The research is led by Ben Davis, Professor of Organic Chemistry at University of Oxford and is the latest breakthrough in AIDS research.

Moreover, the largest candidate vaccine trial in Thailand indicated that an agent, RV144, can reduce the chances of acquiring an HIV infection by a third.  Although the results and statistical significance were small, this discovery may help us immunize people against the virus and ensures that it is possible to do so.

Another research published last month also provided some breakthrough in AIDS research as they identified two antibodies, which neutralize a wide range of HIV strains.  These antibodies maybe used in designing the vaccines that are far more effective than the RV144.

However, Professor Davis offers a novel method in combating HIV through creation of improved vaccines using the field of synthetic biology.  The scientists are pursuing to recreate natural molecules with slight modifications in hope that they would be pathologically useful.  When HIV binds to the T-cells of the immune system, it uses a surface molecule, glycoprotein 120 (GP-120) in order to infect them.  Although most of the GP-120 mutates quickly, one segment of it always remains uniform, the silent face.  The silent face could be a key target for antibodies produced by vaccines.   The silent face is invisible to human immune system because it is coated by sugars which are too complicated for antibodies of the immune system to distinguish and remove.  “The virus uses this trick to decorate itself with what is effectively camouflage.  It has a cloak of invisibility, as it were,” said Professor Davis.   In most patients, as the silent face goes uncovered, the immune system does not produce antibodies against it; however, in one patient an antibody has been discovered, 2G12.

Davis’s team formulated synthetic sugars which surround the virus’s silent face and slightly altered it so that it would be easy for the immune system to identify it.  Through lab tests, researchers discovered that 2G12 antibody binds to these synthetic molecules, concluding that they should prepare and teach the body to make these antibodies.  “We’ve done the whole thing with chemistry,” he said.  “We’ve built constructs that look like the silent face, but which the body recognizes as being unnatural.  We hope it will create an immune response.  We’re turning the virus’s shield into its Achilles’ heel.  If we can build something that elicits antibodies towards the silent face, we could have a vaccine against HIV.”

In order to test the synthetic silent face molecules, 30 different ones have been created which are implemented in rabbits to reveal whether or not their body would encourage the production of antibodies to fight the silent face.  The results should be available within three to six months.

Remaining hopeful, Professor Davis said, “As soon as one shows neutralizing properties, we hope within two years we could see it in people.”

Related posts:

1. Antibodies that may Prevent HIV
2. Dirty Showerheads & Bacteria

British researchers discovered that removal of a gene associated with nutrients and growth allowed the mice to increase their lifespan by 20 percent, justifying why eating less is better for your health and can increase longevity. A drug that could target this specific gene can also combat aging-related diseases.

“What we have shown is that this gene is one that regulates life span and also determines how healthy animals are in middle and late age,” said Dominic Withers of the Center for Diabetes and Endocrinology at University College London.

The mice were bred by removing the ribosomal S6 protein kinase 1 (S6K1) gene that allowed their bodies to conduct in a “similar way to mammals whose calorie intake is restricted,” said the researchers.

“These mice were resistant to type 2 diabetes … and they also appeared to have reduced incidence of the mouse-equivalent of osteoporosis — so they had stronger bones,” Withers said.

Not only were the mice treated by an experimental condition that enable them to live longer, but they also had improved balance, strength, coordination, suggesting a healthier brain. “Our results demonstrate that S6K1 influences healthy mammalian life span,” the researchers wrote in their study.

In the past, studies about calorie restrictions have discovered that eating less does have long-term benefits and many researchers are hoping to replicate their findings in people through drugs. Withers knew of many pharmaceutical companies attempting to manipulate the S6K1 pathway, hoping that it would prevent age-related diseases, if the treatment or drug were safe.

A similar gene, the AMP-activated protein kinase, AMPK was also on the same pathway as S6K1, suggesting that current drugs which target the AMPK may also produce similar results of increased longevity and improved health. Metformin, a common diabetes drug which stimulates the AMPK, could be used to test this hypothesis.

However, since there is a difference between lifespan of mice and human beings, researchers are uncertain about the extent to which the drugs would affect human health and lifespan. But the researchers remain hopeful as Withers said that the study has been conducted in mice and monkeys and has the potential to offer clues into the human functions.

“The big implication is that intervening in aging protects against a broad spectrum of aging-related diseases, and there is now a druggable pathway providing a means to do this which could be used, in principle, in people,” he said.

Related posts:

1. Resveratrol: Anti-Aging Miracle?
2. Antibodies that may Prevent HIV
3. Smallest Laser makes DNA Manipulation Possible

Hormones:
Most of us suffer from acne during puberty when our body begins to produce hormones called androgens.  These hormones over-stimulate the sebaceous glands, which release an oily lipid secretion.  The secretion is stimulated by adrenal glands and gonads.

Sebum Production:
Sebaceous glands secrete sebum which is a lipid product made up of triacylglycerides, cholesterol, proteins and electrolytes.  Because of the overstimulation of the sebaceous glands by androgens, there is an excessive production of sebum.  As the sebum travels up the follicle and onto the skin surface, it mixes with bacteria and dead skin cells.  This extra production of sebum clogs up the follicles, causing acne.  During adolescent years, the sebum production is at its peak and usually decreases after twenty years.

Bacteria:
On our skin surface lays the bacteria Propionibacterium acne, which maintain the sebum production system.  However, when follicles are plugged, the bacteria quickly multiply, causing inflammation.  These bacteria use sebum as a nutrient for growth; the increase in sebum production allows the bacteria to rapidly increase in number as they have the necessary nutrients for growth.  Through chemotaxis or inflammatory response, the body sends white blood cells to attack the exceeding number of Propionibacterium acne.  As a result, the pimples tend to become red, swollen, and sometimes even painful.  There is also an accumulation of pus as the white blood cells hydrolyze free fatty acids in the follicles.

Follicular Obstruction:
In people with acne, sticky squamous epithelium lines the follicle.  In most people, dead cells from the follicle are shed away as they move to the skin’s surface.  However, in people with acne and increased sebum production, these dead cells are not shed away properly and become adhesive to the follicles.  Sometimes, these cells are shed away at a quicker rate, creating a mixture of sebum and dead skin cells.  This results in the obstruction of follicles and thwarts the skin from naturally renewing itself.

Genetics:
Sometimes the cause of acne is due to the genetic factors or traits we have inherited from our parents.  Researchers have not yet discovered the specific genetic factor that affects acne.

Related posts:

1. Hair Pigmentation: Why does it Gray?
2. Healthier Skin: Only a Few Steps Away

The study include 1,169 subjects both nondiabetic men and women who had been previously hospitalized for their first heart attack.  The subjects had to fill out a uniform health questionnaire, which had questions regarding chocolate consumptions within the past 12 months.  Chocolate, through previous researches, has been known to contain flavonoid antioxidants that are presumed to be beneficial for cardiovascular diseases.

Three months after being discharged from the hospital, the patients were involved in health examinations and were followed by researchers for the next eight months.  The researchers also used the Swedish national registries of hospitalization and deaths in order to examine their patient’s activities within those eight months.  In order to legitimize the study and ensure that the consumption of chocolate was causing the increase in survival rate, researchers had to control age, sex, obesity, physical inactivity, smoking, education, and other factors.

However, before concluding that this study shows a cause and effect correlation, we must scrutinize the study’s weaknesses.  The fact that the study was observational and not randomized suggests that we cannot ascertain that it was cause and effect.  Although researchers had considered many other factors, they had not accounted for the idea of placebo effect.  It may be that the increase in survival rate was due to the improvement in mental health caused by chocolate consumption. Moreover, the scientists also did not examine what type of chocolate the patients were consuming; milk chocolate is known to have less flavonoid than dark chocolate.  Though the chocolate consumption showed an increase in survival of patients who had suffered from a heart attack, it did not confirm a reduction in risk for nonfatal cardiac events.

The study does have many factors that could invalidate the results; however, Dr. David L. Katz, an associate professor of public health a Yale believed that the study was “an interesting element, following a group of adults who’ve had a heart attack and noting an impressive reduction in cardiac deaths.”

Another interesting component of the study was that as the patients consumed more chocolate, their risk of death decreased.  Compared to the patients who consumed no chocolate, those who ate it less than once a month had a 27 percent reduction in risk of cardiac death; those who ate it once a week had a 44 percent reduction, while those who ate it twice or more a week had a remarkable 66 percent reduced in risk for cardiac death.

According to Dr. Kenneth J. Mukamal, an associate professor of medicine at Harvard, there has been tons of data suggesting that chocolate lowered blood pressure, which might be the reason why there was a decrease in risk of cardiac death in this particular study.

Dr. Katz said, “I like the study.  It adds to the general fund of knowledge we already have.”

However, before we all begin replacing health snacks with chocolate, Dr. Mukamal suggested a note of caution, “Although this is interesting and provocative, chocolate does not come without costs.  For people looking for a small snack to finish a meal, this is a great choice.  But it should be supplementing healthy eating and replacing less healthy snacks.”

Related posts:

1. Can Breast Feeding reduce cancer?
2. Ted Kennedy’s Death: Analysis of Glioma
3. Green Tea & Cancer: Is there a link?

Within 90 minutes five of the teachers became ill and reported symptoms to authorities.  The brownies tested positive for cannabinoids and after seeking medical advice two of the teachers were also tested positive for THC, an active substance in marijuana.

“They didn’t know they were eating pot brownies, so it’s not the same symptoms as someone who deliberately ate them at a party and got high,” Ms. Fogleman, one of the teachers reported.

The teachers eventually recovered and the sidewalk vendor also disappeared after making a meager $1.50 for each brownie.

…wonder how the teacher didn’t realize she was buying a stash of ‘special’ brownies.

No related posts.

A research of fifty showerheads from nine different U.S. cities showed that about 15 showerheads or 30 percent of them contained high levels of Mycobacterium avium which when inhaled or consumed cause lung infections.  These researchers from University of Colorado stated that the amount of Mycobacterium avium found in these showerheads was almost 100 times higher than the number found in household water.

Norman Pace, a researcher, stated, “If you are getting a face full of water when you first turn your shower on, that means you are probably getting a particularly high load of Mycobacterium avium, which may not be too healthy.”

Mycobacterium avium causes pulmonary diseases, which exhibit many common symptoms such as fatigue, breathlessness, and lasting drug cough.  It usually attacks people with deteriorated immune system, but it may sometimes infect others that are healthy.

Pace believes that the increase in pulmonary diseases from “non-tuberculosis” mycobacteria may be caused by people engaging in more showers and fewer baths.  As the showerhead sprays out the water, droplets filled with pathogens linger within the air causing one to inhale the pathogens into the deepest parts of their lungs.  The Mycobacterium avium are able to survive within the showerheads because of the warm, dim, and moist insides where the bacteria are able to form “biofilms.”

Although this might have little to no effect on healthy people, researchers recommend people with deteriorated immune systems to use metal showerheads and replace them as frequently as possible.  “This really shouldn’t concern average, healthy people.  The main concern is for people who are immune-compromised,” researcher Leah Feazel told Reuters Health.

No related posts.

The Process of Hair Pigmentation

Process of Hair Pigmentation

Like our skin, hair get’s its natural pigment from the formation of melanin.  Melanin consists of cells known at melanocytes that position themselves at the openings of hair follicles on the skin’s surface in order to inject themselves into the keratin that our hair is composed of.  Now hair has two types of melanin pigments, a darker brownish pigment known as eumelanin and phaeomelanin, a lighter yellow pigment.  The combination of these two results in the wide array of hair colors.

Throughout the growth of your hair melanocytes continue to pass pigment to keratinocytes, the primary protein substance in hair and nails.  The combination and continual injection of melanocytes leads to different pigments in hair.

So, Why does it Gray?

Pigment production is a complex process and varies depending on genetic factors, one being the Mc1R gene.  The gene is known to have some control associated with the red pigment in human hair and a few other species.  So now what does that have to do with gray hair?

Many families studied have had members with graying hair at early ages, some even as early as their 20’s, clearly proving that genetics plays an important role in determining your hair’s health.  Researchers believe that ethnicity and stress can also be key factors in the production of melonacytes.  Stress harmones may impact the activity and growth of melanocytes, however, a clear link has not yet been found between stress and graying hair.

“Graying could be a result of chronic free radical damage,” says Ralf Paus, professor of dermatology at the University Hospital Schleswig-Holstein in Lübeck, Germany. Stress hormones produced either systemically or …could produce inflammation that drives the production of free radicals—unstable molecules that damage cells—and “it is possible that these free radicals could influence melanin production or induce bleaching of melanin,” Paus says. “There is evidence that local expression of stress hormones mediate the signals instructing melanocytes to deliver melanin to keratinocytes,” notes Jennifer Lin, a dermatologist who conducts molecular biology research at the Dana-Farber / Harvard Cancer Center in Boston.

Another research group suggests that the graying of hair occurs due to a chemical chain reaction caused by a drop in the levels of catalase.  Less catalase means that the hydrogen peroxide in our hair cannot be broken down leading to an eventual build up that bleachers our hair from inside out.  The study hopes to aid in the development of new “anti-graying” products.

Hopefully that answers some of your questions, but a ‘true’ link to the graying of hair has not been clearly defined yet.

No related posts.

Enjoy and feel free to share your own!!

Banana Mask

• 1 ripe banana
• 1 tablespoon honey
• 1 orange or lemon
• Add a few drops of orange or lemon to a mixture of banana and honey.  Mix and apply to face.  Leave on for 15 minutes and rinse.

Clay Mask

• 1 tablespoon green clay
• 3 drops of essential palmarosa oil
• 1 teaspoon apricot kernel oil
• Mix all the ingredients together and add water if needed.  Apply the mask and leave it on for 10 minutes.  Rinse off with warm water.

Milk of Magnesia Mask

• 1 bottle of flavorless Milk of Magnesia
• Apply the Milk of Magnesia to face and rinse after 10-15 minutes.

Apply Mask

• One peeled apple
• 3 tablespoons of honey
• Slice the apple and blend it together with the honey.  Apply to face and rinse with warm water after 10-15 minutes.

Cucumber Mask

• ½ cucumber
• 1 egg white
• 1 teaspoon lemon juice
• 1 teaspoon mint
• Mix all the ingredients and refrigerate for 10 minutes.  Apply to face and leave it on for 15 minutes.  Rinse first with warm water and then cool water for a fresh feeling.

Strawberry Mask

• Four ripe strawberries
• 1 teaspoon plain yogurt
• Smash the strawberries with a spoon or a fork and mix it with the plain yogurt.  Apply the mask to face and rinse off with lukewarm water after 10-15 minutes.

Oatmeal Mask

• 1 cup oatmeal
• 1 teaspoon lemon juice
• 1 tablespoon yogurt
• In a blender, mix all the ingredients listed above.  Apply the paste to face and rinse off with warm water after 10-15 minutes.

Mixed Mask

• 1 boiled potato
• 1 tomato
• Few slices of papaya
• Cucumber
• Blend all the ingredients together to create a paste.  Apply the mask and rinse off after 10-15 minutes.

Juice Mask

• Tomato juice
• Cucumber juice
• Lemon juice
• Calamine powder or gram flour
• Using the ingredients listed above create a paste.  Apply it to face and rinse off with warm water once the mask is dry.

Carrot Mask

• Carrot
• Lemon Juice
• Blend the carrots and lemon juice to create a paste.  Apply it to skin and rinse off after 10-15 minutes.

Related posts:

1. Homemade Face Masks for Normal Skin
2. Remove Spots Naturally
3. Healthier Skin: Only a Few Steps Away

Those who have acquired trichomoniasis, an STD caused by Trichomonas vaginalis, were slightly more likely to develop prostate cancer, compared to those who were not affected by this STD.  However, more importantly, the study suggests that the STD might result in a formation of a more aggressive prostate cancer as Lorelei A. Mucci, epidemiologist and co-author of the study states that “they were nearly three times as likely to die of the disease once they had prostate cancer.  Our finding suggests that infection may make prostate cancers more aggressive and more likely to progress.  ”

The study included analysis of 673 men who developed prostate cancer and 673 men who did not.  The patients were also examined to see if other environmental factors were affecting the results such as age or smoking status.  Some of the 673 men who developed prostate cancer had an account of trichomoniasis as confirmed by their blood samples.

A previous study done by Mucci and his colleagues on Sept. 9 in the Journal of the National Cancer Institute, also reported similar findings: a link between STD trichomoniasis and aggressive prostate cancer.

Although the two studies had similar results, there are many doubts as the aggression of prostate cancer could be caused by inflammation, which is the result of an infection.  Moreover, previous studies have not found a link between STDs and prostate cancer; however, these studies did not have the lengthy and scrutinizing follow-up like the newer studies, according to Durado Brook, MD, MPH and director of prostate cancer at the American Cancer Society.

“We can say from this study that there may be a link between this sexually transmitted infection and more aggressive prostate cancer, but more research is needed to confirm this,” he says.  However, researchers remain hopeful as an affirmation of this link can provide insight into the aggression level of prostate cancers.

Related posts:

1. Tamoxifen: Causing Breast Cancer?
2. Can Breast Feeding reduce cancer?
3. Green Tea & Cancer: Is there a link?