Qualitative Detection of Glucose in Urine

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Glucose is not present in urine, in general because in the kidneys, glucose is reabsorbed from the filtrate of glomerulus, across the tubular epithelium of proximal tubule into the bloodstream. Therefore, normal glucose range in urine is 0 mg/dL, or rarely up to 15 mg/dL. If higher than normal levels of glucose (0-15 mg/dL) is found in urine, then it can be suspected as diabetes, pregnancy, or renal glycosuria. Presence of glucose in urine was commonly tested to monitor diabetes in the past. Now, blood tests for glucose is easier than urine test. The glucose urine test may be done when there is suspect of renal glycosuria.

One of the test is based on the basis of character of glucose as it is a reducing carbohydrate because of a free aldehyde group. During the reduction process of Cu(OH)₂ to CuOH by the glucose aldehyde group, and itself is converted into a carboxyl group. CuOH and its degradation product, Cu₂O, are colored compounds. In excess of CuSO₄, the high Cu(OH)₂ content may lead to the formation of black CuO particles. This is called Trommer’s reaction and explained in the following equations;

Trommer's Explannation

Karl Trommer (1806-1879), German chemist first developed this copper reduction test in 1841, and more stable copper sulphate reagent was explained by Hermann von Fehling (1812-1885) in 1850. Even more sensitive copper reagent was described in 1908 by Stanley Benedict (1884-1936). Later, Ames (1945), the research team led by Albert & Helen Free, developed Clinitest tablet, which contained cupric sulfate, sodium hydroxide, and citric acid mixed with a bit of carbonate to make it fizz. Helen M. Free (1923-) and Alfred Free (1913–2000), revolutionized diagnostic urine testing with their invention of a chemically coated paper dipstick that measures a patient’s blood/urine sugar by changing color when dipped in a blood/urine sample.

Determination of protein concentration

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Introduction
Finding the exact quantity of proteins in a solution is very often necessary in the biochemical practice and to analyse clinical samples as well as in research. There are many ways to measure protein concentration. In chromogenic methods, the absorbance of a coloured product formed by the protein and an organic molecule is measured. Protein concentration can also be determined from the protein's own (intrinsic) UV absorbance. However, these methods may give different results for different proteins of the same concentration. Also, different methods can yield somewhat different results for the same protein. Also, dilution factor may be a important parameter.

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There is no absolute photometric protein concentration assay. All methods have advantages and disadvantages and we must choose among them by taking the following aspects into consideration: specificity, sensitivity, the measurable range of concentration, the accuracy, the nature of the protein to be examined, the presence of materials interfering with the measurement, and the time required for the measurement.

Principle
Biuret test
Molecules with two or more peptide bonds react with Cu²⁺ ions in alkaline solution and form a purple complex. Nitrogen atoms of the peptide bonds form a coordination bond with the metal ion. The quantity of the complexes formed is proportional to the number of peptide bonds.

In practice, the determination of protein concentration is done using a calibration curve created using samples of known concentration. The protein treated with biuret reagent is measured at 540 nm after the purple product is formed.

The advantages of the method include that only few materials (e.g. Tris and amino acid buffers) interfere with it, it can be done in a short time and does not depend on the amino acid composition of the protein. Its disadvantages are its low sensitivity and that it requires at least 1 mg of protein.

Lowry (Folin) protein assay
This is sensitive technique where a coloured product is formed similarly to the biuret reaction, but a reagent strengthen the colour, which is kown as Folin–Ciocalteu reagent (a mixture of phosphotungstic acid and phosphomolybdic acid in the Folin–Ciocalteu reaction). The reaction mechanism is not well understood, but involves reduction of the Folin–Ciocalteu reagent and oxidation of aromatic residues (mainly tryptophan, also tyrosine). The strong blue colour is created by two reactions: (1) formation of the coordination bond between peptide bond nitrogens and a copper ion and (2) reduction of the Folin-Ciocalteu reagent by tyrosine (phosphomolybdic and phosphotungstic acid of the reagent react with phenol). The measurement is carried out at 750 nm.

As in the biuret reaction, a calibration curve is created (for example using BSA, bovine serum albumin), and the concentration of the unknown protein is determined from the curve.

The advantages of the method include that it is quite sensitive and is able to detect even 1 µg of protein. Its disadvantages are that it takes rather long to carry out, is disturbed by various materials (including ammonium sulphate, glycine and mercaptans) and that the incubation time is critical. As different proteins contain different amounts of tyrosine, the amount of the coloured product will also be different. As a consequence, this method is more suited to compare the concentration of solutions of the same protein than to absolute measurement.
Source:

List of Experiments for Biochemistry Laboratory work

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                        List of Experiments for Laboratory work
Course Title: Laboratory work I: Biochemistry (Microbiology)
Credit: 1                                                                                                                                  

1. Preparation of normal, molar and percent solutions.
2. Preparation of different buffer solutions and measure their pH.
3. Determination of the isoelectric point of casein (of milk).
4. Titration of amino acids and find the physical constants.
5. Study the effects of temperature and pH on the enzymatic activity of salivary amylase.
6. Estimation of given protein concentration by Bradford, Lowry (Folin) protein assay and by Biuret test.
7. Qualitative detection of glucose in urine (the Trommer reaction).
8. Quantitative determination of glucose in blood by a glucose-oxidase method.
9. The determination of activity of the Krebs cycle dehydrogenases in the liver.
10. Determination of total cholesterol concentration in serum.
11. Determination of urea concentration in serum and urine.
12. Quantitative determination of phospholipids concentration in serum.
13. Determination of saponification value of the fat.
14. Separation of amino acids by chromatographic techniques and detection by nin-hydrin test. 

A Strategy Game in Linux Environment, 0 AD (zero-ey-Dee)

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If you are fond of strategy game, 0 A.D. (zero-ey-dee) is one of the best game, which is available in Linux (also in Windows and Mac). It is a free, open-source, historical Real Time Strategy (RTS) game.

The game winning secrets resembles with the “age of empire 2,” i.e., build more and more modern weapons and attack as soon as possible. Defensive strategy hardly works.

However, currently it is available only in alpha version, by Wildfire Games. Even though it is in alpha phase. I have tested and it is working well in Ubuntu 12.04 LTS except the movement became very slow in some missions.

0 AD provides a platform not only for playing game, but also we can build a scenario and map ourselves. Here are some print-screens.

Is Debian the Most Stable Linux Distro?

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I have been using Fedora for many years. Fedora is the leader out-breaking new software. I have found many research related software are more comfortable in fedora than some other Dostros, which I have tested. But the greatest drawback of this OS is the instability and crashing of several times. Surprisingly windows 7 showed great improvement, however, it is not freeware.

Because of YUM and RPM system and is bluish configured, I had shifted in CentOS. Although CentOS is designed for server, it was good in desktop also. And I could install research related software and they were working well, however, not good for Skype. But when I made update a few days after installing 6.3, the system did not start. There was no facility for bug report at that case. It booted only and hanged on log in screen. I had restarted several times but same problem persisted.

Then I tried Linux Mint. I surprised with its awesome feature. Really, it was very good looking. But yesterday when I updated Linux Mint 14, Nadia, I got the same problem as CentOS. Does it mean Linux OS are still in infancy in terms of reliability and stability.

Probably, I have to try Debian but may I install the latest version of some software such as Libreoffice, VLC, Autodock, Chimera, etc.

At this stage I need such Distro, which is stable for at least for 2-3 years without compromising for the latest software and security. I mean the software / application could be installable a few months later than the final release date, if not immediately. Please comment if you have any idea.

Online courses by reputed universities free of cost

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No doubt, Nepal is one of the poorest countries, however, our education and courses, syllabus is still competitive. Further study in reputed university is very difficult for us because our government never supports for any scholarships, unlike other developing countries. Here are some websites where we can find some lectures offered by MIT, Harvard University, etc. These are absolutely free. Though, we have very slow internet and limited time of electricity supply, still we can try.
EdX (Most of the courses are about electronics, computer, physics, etc.)
Coursera (This offers a wide range of courses including physics, computer, biology, etc.)

Lipid Structures

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Some structures of lipid. Forget about exact geometric isomerism and stereocenter.

Simple Lipids

Prostaglandin

Scholarships in China for Nepalese

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Three Gorges University (CTGU), Yichang, Hubei, China has offered the fellowships for Nepalese. This is  one of good options to pursue a degree in China. It will provide 10 scholarships each year including Hydro-power and electrical engineering (4), medicine (2), Chinese language (2) and Business Studies (2).  Prof. Dr. Krishna Adhikari and Ex-PM Madhav Kumar Nepal has facilitated for this MoU. How much stipend will they provide? Not confirmed yet. Source:Gorakhapatra

In addition, Chinese Academy of Science also provides PhD fellowships under TWAS-CAS scheme, which provides at least $500 per month and this is sufficient to cover a good living expenses. 

How Does Bovine Serum Albumin Protein Look Like?

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If you are a biologist, serum albumin protein is very common to us. It is one of the abundant proteins in our body as well as the component of egg. Here are the some pictures of the bovine serum albumin that I have drawn using a software and x-ray crystallographic data deposited in protein data bank (3V03).

Ribbon structure of bovine serum albumin in black background

Ribbon structure of bovine serum albumin in black background side view

Ribbon structure of bovine serum albumin (3V03) in white background front view

Ribbon structure of bovine serum albumin in white background side view

Ribbon structure of bovine serum albumin (3V03) in white background left view

Tips to Prevent the Spread of Infectious Diseases

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Let's admit it, nobody wants to be sick. From the common cold to more serious strains of the flu, many infectious diseases run rampant through modern society. You cannot just stop all contact with the outside world in order to stay healthy, but there are many ways you can help lessen your odds of contracting an infectious disease. If you want to stay healthy even when surrounded by sick people, here are six ways you can help prevent contracting an infectious disease.

1. Wash Your Hands
One of the most important ways you can be proactive in preventing the spread of infectious diseases is by washing your hands. Everything you touch can contain disease causing microbes and the best way to avoid these microbes from causing illness is by washing your hands. To get the most out of hand washing, make sure you washing your hands vigorously for about 20 seconds. This should wash away all the unhealthy germs.

2. Stop Sharing
If you truly want to protect yourself from an infectious disease, refrain from sharing personal items like toothbrushes, makeup, towels and razor blades. Sharing these items can increase your chances of contracting an infectious disease.

3. Get Vaccinated
A wide variety of vaccinations can help you protect yourself from contracting infectious diseases. If you want to eliminate your chances of obtaining one of these horrible illnesses, stay up to date on your vaccinations and get a yearly flu shot.

4. Cook Safely
Many infectious diseases are caused by unsafe cooking habits. Before you cook, make sure you thoroughly wash your hands so to avoid contaminating the food your are cooking. Also, make sure foods like vegetables are washed properly so to clean away possibly bacteria.

5. Safe Sex
Though it is not common in Nepal, because of cultural and tradition. Many infectious diseases are spread through sexual contact, and that is why it is important to wear a condom each time your have sex. If you are in serious relationship, ask your partner about his or her sexual past and if necessary, have that person submit to std testing if you want to engage in sexual acts without the use of condoms.

6. Travel Cautiously
In a variety of countries, there are an abundance of diseases that are not necessarily seen in America. Before you travel abroad, make sure you are aware of the types of illnesses that are common to the country you will be visiting. Be sure to get the vaccinations needed for a health and safe vacation.

Fortunately, the risk of contracting an infectious disease can be minimized greatly if you follow the six above listed tips. In order to protect your health, always remember to wear a condom, be a cautious traveler, cook food properly, wash your hands, get vaccinated, and never share personal items. At that point, you can be certain that you will be doing all you can to help protect yourself from contracting an infectious disease.

This is guest post by Ian Watertown who writes about health, travel & more here.

How the World of Medicine is Changing Today

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Each day the pharmaceutical industry is making further strides in creating medicines to help a variety of different ailments. In the past 100 years, medication has gone from helping people live to be 50 to helping people live until 80 and beyond. Why is this? It is because the pharmaceutical industry is constantly developing even better medications and with better medication comes the possibility of a longer life span. The world of medicine is constantly evolving and here are some of the ways medication is evolving today.

1. Choice
From medications that help control the symptoms of diabetes to inhalers that help asthmatic people breathe, the pharmaceutical industry has created a variety of different medications to help alleviate the symptoms associated with many common illnesses. This means people have more choice when choosing medications. This is a great change from the medications of years past.

2. Availability
In today's world of medicine, it is now possible to help those in disease stricken countries obtain the medications they need for a healthier population of people. Each day, more and more people in poor countries are receiving the medication they need to survive.

3. Vaccines
The pharmaceutical industry is constantly coming up with vaccines that can help protect against a variety of different diseases and illnesses. Since the flu shot to vaccines that helps prevent girls from contracting HPV, the world of medicine is always researching and creating new vaccines. The vaccines of today are more advanced than the vaccines of years gone by.

4. Compounding Results
Because of advances in medicine, people have more options when it comes to taking care of their health. When people realize there are a variety of treatment options for what ails them, it may encourage them to get the help they need to manage their illness. This in turn will create a healthier population of people. In years gone by, people did not have the healthiest options available today and that is a major change in medicine.

5. Where the Heart is
Heart disease is a major problem for many people. Because of this, plenty of research has been done to help make heart surgery more successful. Many people may one day require heart surgery and with changes in medicine, it is more likely that the surgery will be a success.

6. Wellness
One major change in medicine that is certain to gain more attention in the years to come is the ability to monitor at risk individuals before they get sick. Through the use of genomic medicine, it may one day be possible to predict a disease before it occurs so a person can take preventive measures that may stop the disease ahead of time.

Modern-day medicine is changing constantly. As a result, people are experiencing longevity and a higher quality of life. Thanks to advances in medical technology, the world of medicine is evolving for the better on an almost daily basis - as can be seen by the examples listed above. Now all we have to do is wait for whatever is the next :)

This is guest post by Jenna Hayworth who writes about health, current events & more here.

Call for Abstracts ICIDN-2012 Conference (Dec. 15-18, 2012)

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Message on the behalf of Santosh Thapa, ICIDN Secretariat

Dear interested all,
We are now accepting abstracts for oral and poster presentation at the "First International Conference on Infectious Diseases & Nanomedicine-2012 [ICIDN-2012]" scheduled on 15-18 December, 2012 in Kathmandu, Nepal. Abstracts can be submitted by Undergraduate/Post-graduate students or early career Scientists, Researchers, Professors and can be on any topic in infectious diseases and nanomedicine.To submit your abstract, please follow the following two step process.

(1) Download the Abstract Template from. The guidelines for preparation of abstract is also included within the template.
(2) Email your abstract (maximum one page) to icidn2012@gmail.com, mentioning the preferred way of presentation (oral or poster).

The deadline for abstract submission is : 15 October, 2012
Decision regarding your abstract will be communicated to you by email before: 31 October, 2012. For papers to be included into the conference final program, the author must register by: 1 November, 2012. We look forward to Welcoming you in Kathmandu in December this year.

Thank you.
With warm regards,
Santosh Thapa
ICIDN Secretariat
P. O. Box 24411
Kathmandu, Nepal