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Saturday, April 18, 2009

All About Blood: Back to Basics





Blood is red when oxygenated and turns blue when deoxygenated.

The blood smells like metal rust due to the presence of iron (Fe) which sits at the centeal structure of the red blood cells.
Let's start with agglutinogen. What is agglutinogen or antigen? It simply a protein in the blood that has the capacity to agglutinate or clump together which might result to death during blood tranfusion. When red blood cell clump together to form a mass or body, it will obstruct the flow of blood thus resulting to decrease oxygen level in the body resulting to death. There are two types of agglutinogen: Agglutinogen A and Agglutinogen B.

These agglutinogens are inherited in such a manner that some people may have one, may have both simultaneously, or neither of them on their cells.

O-A-B Blood Types
Blood Types are classified into O, A, B, and AB depending on the presence or absence of
the two agglutinogens, the A and B agglutinogens.


Simplifying the Jargon
Let's start with blood type O has genotype or allele of OO, does not contain any agglutinogen but contains agglutinin A and agglutinin B. When we say agglutinin it attacks agglutinogen to form a clump of cells. For example agglutinin A will attack A agglutinogen thus forming a coagulate leading to blood vessel blockage, that's the rule of thumb for other blood types. In simple terms, agglutinin attacks/binds agglutinogen. Blood type A has two genoytypes AO and AA , contains agglutinogen A and agglutinin B. The agglutinin B will attack B agglutinogen forming clumps of cells. Blood type B has BO and BB genotypes, contains B agglutinogen and agglutinin A. Blood type AB has a genotype of AB with A and B agglutinogens, not containing any agglutinin.Please keep this in mind. Please see the table for summary of the discussion.
Why Blood type O is said to be the universal blood donor? The answer is that patients with blood type A or B can receive blood type O ( because BType O does not contain any agglutinogen).
Blood type O patients should receive blood type O only. You cannot give them blood type A or B, blood cells will clump if unattended it would lead to death.
Why blood type AB is called or considered as royal blood? People with this blood type can receive AB blood type ONLY. You cannot give them blood type O since it contains agglutinin A and B. Only about three percent of the population have this blood type. That's why it is called a royal blood.

The Use of O-A-B Blood Type for Paternity and Maternity Test.
Again, each blood has its own genotype:
Type A has AO AA
Type B has BB BO
Type AB has AB
Type O has OO
Questions:
1.






Friday, April 17, 2009

IRRI JOB OPENING-Editor

This is just a temporary post.

IRRI
International Rice Research Institute
Human Resources Services
Communication and Publications Services (CPS) invites applicants for the position:
Assistant - Editorial (2009-R-46)
Basic purpose : The successful candidate will provide editorial and secretarial support in producing science publications, and ensure the timely publication of IRRI serials and monographs, including International Rice Research Notes (IRRN) through Open Journal Systems (OJS)
Major responsibilities:
Provides support in editorial and secretarial areas in producing publications.
· Keyboards corrections for various publications, including the IRRN, proceedings, Discussion Paper Series, Limited Proceedings, Technical Bulletins, news releases, and other materials such as donor reports, concept notes, and project proposals.
· Uses Open Journal Systems (OJS) in managing IRRN submissions and ensuring that the whole editorial process for all submissions is running efficiently until accepted manuscripts are published online using the same open-source technology.
· Formats and ensures completeness of manuscripts before signing off on them for layout (e.g., Discussion Paper Series, Limited Proceedings, and Technical Bulletins).
· Checks reference citations for format and style and for accuracy.
· Does publication layouts (e.g., Discussion Paper Series, Limited Proceedings, and Technical Bulletins) if needed.
· Organizes and maintains databases (either using a simple spreadsheet or other appropriate software) for all incoming editing jobs (e.g., journal articles, papers for technical publications, IRRN submissions, other materials).
· Monitors movements and status of submitted manuscripts (e.g., technical publications, journal articles, IRRN submissions).
· Proofreads manuscripts, reports, and page layouts of publications and other materials for accuracy and adherence to Institute and other relevant publishing guidelines.
· Coordinates procedural tasks of in-house and outsource personnel in layout and design of publications.
· Assists in preparing and coordinating materials (e.g., manuscripts/page or layout proofs in CD format or hard copies) for sending to editors or service providers.
· Performs necessary follow-up or relevant action regarding areas of concern.
Provides secretarial services/administrative support to the Editorial section and administrative support to other CPS sections.
Performs other duties as may be assigned by the supervisor.
Qualification requirements:
Minimum education : Bachelor's degree in communication arts, computer science, or related field
Experience required : 2–3 years' experience in communication work or publishing, including multimedia production
Skills and abilities : Excellent written and verbal communication skills, computer application knowledge and skills required (Microsoft Office suite, Adobe suite, InDesign, Content Management Systems software, e.g., Joomla, Open Journal Systems)
Applications : Qualified candidates should submit letter of application, comprehensive résumé, transcript of records, and names and contact details of 3 referees to IRRI Recruitment at the HRS Office, F.F. Hill Building, IRRI Los Baños, Laguna, or email to IRRIRecruitment@cgiar.org. You can also mail application with complete requirements to
Assistant - Editorial (2009-R-46)
Human Resources Services
International Rice Research Institute
DAPO Box 7777, Metro Manila
*Screening will start on 17 April 2009 and will continue until a suitable candidate is identified.

Information Campaign Against MYOPIC EYE





What is myopia?

Myopia is a medical term for shortsightedness. The first sign of the disease is seeing far objects a little bit blurry. The eyeball is too long, or the cornea is too steep, so images are focused in the vitreous inside the eye rather than on the retina at the back of the eye (wikipedia). Most opthalmologists and optometrist would correct the defect by prescribing glasses or contact lenses. It can also be corrected by LASIK, a refractive surgery of the eyes. People with myopic eye have a very high positive refractive power so the lenses prescribed are the negative diopters. Well, diopters is the optical measure of the refractive power of the lens. For more information(http://en.wikipedia.org/wiki/Myopia or watch http://www.youtube.com/watch?v=0oYkZRBvLiA ).
Illustration
Here is how they correct myopic eye with a concave lens( Thinner at the middle, thicker at the edges or sides). Concave lens diverge light source in order to focus the image directly in the retina.
Degree
Myopic eye has positive diopters which means too high optical power or high refractive power which can be corrected by negative diopters of concave lenses.
Myopic Severity is classified as:

1. Low myopia usually describes myopia of −3.00 diopters or less ( 300grade or less).
2. Medium myopia usually describes myopia between −3.00 and −6.00 diopters( 300-600grade). Patients are positive with pigment dispersion syndrome or pigmentary glaucoma
3. High myopia usually describes myopia of −6.00 or more(> 600 grade). They are likely to have retinal detachments and primary open angle glaucoma. They may experience floaters, shadow-like shapes which appear singly or in clusters in the field of vision. Thirty percent of myopes have high myopia
Epidemiology:
The prevalence of myopia has been reported as high as 70-90% in some Asian countries, 30-40% in Europe and the United States, and 10-20% in Africa( Source wikipedia).
Well this incidence is highly prevalent in Japanese and Korean people. Japanese are known for their electronic work and highly meticulous and detailed art. Well, Koreans are known for their love of computer games and also for their electronics.
Highly educated people have higher cases of myopia than their counterparts.
Causes:
1. genetic - abnormalities in the PAX6 gene
2. environment - extensive near work( excessive reading, computer games).
Remedies:
For officeworkers:
1. Learn to relax your eyes every 30 mins when working in front of the computer or reading by looking at far away objects.
2. Engage in physical activities like sports ex. jogging religiously.
3. Have a good nutrtion for your eyes.
Comment
I have a low level myopia and I intend to rest my eyes every 30 mins when reading or working in front of the computer. I try to relax my eyes by looking at a far away greeny objects like trees or any plant. I am starting to wear a low positive diopter lens to help my eyes while focusing near objects.
Suggestion
For best advise or opinion, consult your doctor.

Read Bates Method suggesting the use of eye exercise.
For more info(http://en.wikipedia.org/wiki/Bates_Method)

Thursday, April 16, 2009

Growing Concerns Regarding Breast and Cervical Cancer

Breast Cancer



Cancer is a word derived from the crab shaped tumor removed from the women breast using crude surgery about 2000 years ago. Breast cancer is a genetic disease which can be aggravated by the stress in the environment. It can also be attributed to hormonal imbalance particularly estrogen and progesterone. According to medical practice, it is a must to check your breast for a possible occurence of tumor.Tumor or tumour is the name for a swelling or lesion formed by an abnormal growth of cells(http://en.wikipedia.org/wiki/Tumor). I want to caution everyone that not all tumors should be a cause for alarm. Tumor can be classified as benign or malignant. Benign means it is solitary and does not invade adjacent tissues and organs.The picture below illustrates a benign tumor in the face./ Malignant tumor is the one associated with cancer which is mobile and capable of invading other tissues and organs.

Breast cancer is one of leading cause of death in women today. Therefore, regular breast examination should be done by you or if necessary your trusted medical personnel. If you observed that you have hard lump or small balls in your breast before regular menstruation(reg. menstruation 20-32d of the mo.), consult your doctor. Breast examination can be done quadrant method or by clock method. For the specifics of breast examination, visit the site or watch (http://www.youtube.com/watch?v=Po2lGo7LIPM or http://www.patient.co.uk/showdoc/40000260/) .


Cervical cancer

It is a contagious and communicable disease that can be acquired through physical contact even the slightest skin contact (open wound) with infected body fluids. The leading cause of this disease is the human papilloma virus. In the Philippines, high incidences of HPV associated cervical cancer was brought about by the Overseas Filipino Workers from Saudi and Europe.
This disease will not give you early symptoms until the level of fatality is high. For sexually active individuals, please do get your regular Pap smear.

This is a sexually transmitted disease that can enter the female body during coitus or sexual intercourse with a multisexual partner. During repeated tearing and shearing of the vaginal walls, breaks will be an avenue for the entry of HPV. Cancer begins and then the genital warts.

Is it treatable?

Again the old cliche" Prevention of an ounce is better than a pound of cure". Stage III and IV cervical cancer are said to be untreatable.

Surgery, radiation therapy and chemotherapy are the treatment available for stage I and II cancer.


For sexual active individuals(10 to 45 y.o.) , marketable vaccines are now available such as Cervarix (http://www.gsk.com.au/products_vaccines_detail.aspx?view=122) and Quardricil.





For more info.Read my recent updates. Or click the links and ads related to the discussion.

Tuesday, March 4, 2008

Cellphones May Cause Cancer: Science, Technology and Society


According to the British Journal of Cancer(2005), long term exposure to radio frequency (RF) waves from cellphones increases the risk of tumor growth in the brain. This research was further supported by the pooled study showing 96 cases with malignant brain tumor by using a cellphone 1 hour a day for a period of ten years or more.This study also showed there is a higher risk of developing a tumor on the side of the head frequently used when making a call. From the Australian Newspaper,1997 by Steward Fist, A Swedish study showed that heavy users of cellphone had a 240 % increase chance in brain tumor development on the side of their head where the phone is used on. According to REFLEX study funded by several European Nations from the Environmental Health Journal(2006), they found that RF waves from cellphones causes an increases in single and double stand DNA breaks which causes mutation and can lead to cancer and was reported to activate certain genes involved in cell division causing uncontrolled cell growth. This study was further supported by the study conducted by Dr. Singh and Dr. Henry Lai from the Washington State University which revealed same result in rats. RF waves causes thermal and non-thermal effects which adversely affects health and can lead to cancer.
Mice were commonly used in the experiments because they can produce offspring in a shorter time. Man will not expose himself to hazardous conditions in the laboratory and neither he desires to do so. Survey is then used as an alternative to study human beings having cancer associated with cellphones. The basis for comparative medical effects is that mice and human are mammals. DNA level experiments which showed accompanied mutations were the basis of experimental inferences and conclusions. What can be true to mice can be in some ways extrapolated to man but not at all times. This remains a controversy in the field of gene technology and biomedical research especially to those research groups trying to prove that indeed cellphone waves might trigger cancer. In addition, they have to consider the bioethics and animal rights. On the other hand, corporate research groups are also using this method but they are using engineered strain of mices which shows to have tolerance against cancer.
In economics and political terms, unprecented magnitude of the potential effects or consequences of modern Science and technological innovations is popular justification Societal Control of Science and Technology(SCOST). According to McGinn(2002), one major justification of SCOST appeals to the importance of freedom in the form of voluntary choices. It is said that the consumer cannot truly make a voluntary choice because important informations about product choices like features,ingredients, performance and possible effects on health and safety are witholded by companies, then an external party will arise to combat the ignorance by providing the people the access to relevant and important products about the product. In this case, cell phone companies conducts their own experiment to show that their products poses no harm to people.
In the book of McGinn (2002), it states that companies like in this case telecommunication companies are afraid to provide relevant information due to economic reasons because if they reveal those information , it may disclose property trade secrets about the product and will surely increase the price of the product.The mere presence of such information would create unwarranted alarm or anxiety rather than educating the people.This entail a decrease in profit in the case of the firm.One of the possible SCOST intervention points in the life cycle of a scientific or technological endeavor is the emergence of alleged consequence of product which is affected by legislative limitation , product ligatation and regulation.
In the major Western countries, the privates sector influence on Science and Technology is at least as important as the national government. It is the sphere in of business where the primary but not the sole source of societal influence in the private sector came from. It is said that the consuming public is conditioned by corporate advertising. Due to economic reasons and to counteract the results of non-for-profit groups that cell phone can cause cancer, cell phone companies funded their own research groups to prove that cellphone cannot cause cancer.
The issue of 1.6 as SAR(Specific Absorption Ratio) as safe is still questionable. According to some scientist , the 1.6 SAR value is already too high but cellphone companies insist that it is safe.

Mechanism: B to Z DNA Transition

DNA can change its shape to achieve its purposes in life. Z DNA was thought to be an inherently unstable. It was the first non-B form of DNA to be discovered. It contains an alternating sequence of purine and pyrimidine.The orientation of its H-bonded base pairs are turned upside down. Unlike A or B DNA, Z DNA is a left handed helix composed of base pairs in which each of the purines has undergone a rotation from the anti- to syn- conformation.The sequence of DNA strands that form duplexes adopting the Z conformation must alternate purines with pyrimidines (i.e. GCGCGC), and the solvent conditions must usually include high ionic strength or high concentrations of organic solvent. Although the low-energy forms of right-handed duplexes of B-DNA and A-RNA are structurally very different, they adopt similar left-handed Z-conformations (Nakamura et. al,1995).

The discovery of Za protein that specifically binds to Z DNA implicated that this form as a biologically functional DNA component. Today, Za is used to locate B-Z junction. The B-Z junction is the connection between the two forms of DNA.B-Z junction have this orientation major groove of B-DNA joins to the minor groove of Z-DNA whereas the minor groove of B-DNA joins with the major groove of Z-DNA.

Ha et al(2005) group suggested based on the experiments the most acceptable model of B to Z DNA transition that Z DNA formation might start with the breakage a single bp(2 N bases) in the B form then it will swing round at 180 and re-pair Z DNA conformation then the process would continue from the initiation point either unidirectionally or bidirectionally until the entire track is transformed it to Z-DNA helix.The breakage of single bp otherwise known as base extrusion is a well known scheme used by enzymes that edit or repair DNA.Base extrusion can be triggered when the DNA is exposed to extreme conditions like high temperature and also by mutation. The chance of A-T and G-C to be extruded is assumed to be equal. The base pairs with respective B to Z helices retain their standard A-T and G-C base pairing and stacking. Due to the discovery of B-Z junction it is reasonable to believe that Z DNA is stable and energetically feasible and due to the advancement of Molecular Genetics and Biophysics additional roles of Z-DNA is expected to emerge.

References

Ha,et.al(2005).Nature

Monday, March 3, 2008

Warning: Women Beware of Your Cycle

In a news published in Nature Magazine, it was cited that fertile women tend to be more attracted to single unattached men than married men. Whereas, women in a relationship are attracted to coupled men at nonfertile stage. This observation serves as a supporting evidence that oestrus in women which was once thought to be lost in human evolution is alive and well says Eli Finkel, a psychologist from the Northwestern University in Evanston, Illinois. Oestrus is Latin for Estrous cycle which pertains to the physiologic changes occuring in females. In mammals, it is best expressed during menstrual cycle.