Marissa's Blog

Resuscitation of Frozen Cell Lines

2008-06-13T10:16:15+02:00

Many cultures obtained from a culture collection, such as ECACC, will arrive frozen and in order to use them the cells must be thawed and put into culture. It is vital to thaw cells correctly in order to maintain the viability of the culture and enable the culture to recover more quickly. Some cryoprotectants, such as DMSO, are toxic above 4oC therefore it is essential that cultures are thawed quickly and diluted in culture medium to minimize the toxic effects.

A schematic diagram of "Resuscitation of Frozen Cell Lines"

Materials

Media– pre-warmed to the appropriate temperature (refer to the ECACC Cell Line Data Sheet for the correct medium and size of flask to resuscitation into.)

70% ethanol in water

DMSO

Equipment

Personal protective equipment (sterile gloves, Laboratory coat, safety visor)

Waterbath set to appropriate temperature

Glass Bottom Dishes

Microbiological safety cabinet at appropriate containment level

CO2 incubator

Pre labeled flasks

Marker Pen

Pipettes

ELISA plates

Ampule Rack

Tissue

Procedure

Read Technical data sheet to establish specific requirements for your cell line.

Prepare the flasks as appropriate (information on technical data sheet). Label with cell line name, passage number and date.

Collect ampule of cells from liquid nitrogen storage wearing appropriate protective equipment and transfer to laboratory in a sealed container.

Still wearing protective clothing, remove ampule from container and place in a waterbath at an appropriate temperature for your cell line e.g. 37oC for mammalian cells. Submerge only the lower half of the ampule. Allow to thaw until a small amount of ice remains in the vial - usually 1-2 minutes. Transfer to class II safety cabinet.

Wipe the outside of the ampule with a tissue moistened (not excessively) with 70% alcohol hold tissue over ampule to loosen lid.

Slowly, dropwise, pipette cells into pre-warmed growth medium to dilute out the DMSO (cell culture flasks prepared in Step 2).

Incubate at the appropriate temperature for species and appropriate concentration of CO2 in atmosphere.

Examine cells microscopically (phase contrast) after 24 hours and sub-culture as necessary.

Key Points

Most text books recommend washing the thawed cells in media to remove the cryoprotectant. This is only necessary if the cryoprotectant is known to have an adverse effect on the cells. In such cases the cells should be washed in media before being added to their final culture flasks. See Protocol 7 for further details.

Do not use an incubator to thaw cell cultures since the rate of thawing achieved is too slow resulting in a loss of viability.

If a CO2 incubator is not available gas the flasks for 1-2 minutes with 5% CO2 in 95% air filtered through a 0.25m filter.

For some cultures it is necessary to subculture before confluence is reached in order to maintain their characteristics e.g. the contact inhibition of NIH 3T3 (Prod. No. 93061524) cells is lost if they are allowed to reach confluence repeatedly.

Scouce: ECACC Handbook Protocol 2

Biousing Cell Culture Dishes List

2008-06-11T09:07:04+02:00

Cell culture is the process by which prokaryotic, eukaryotic or plant cells are grown under controlled conditions. In practice the term "cell culture" has come to refer to the culturing of cells derived from multicellular eukaryotes, especially animal cells. The historical development and methods of cell culture are closely interrelated to those of tissue culture and organ culture.

Animal cell culture became a routine laboratory technique in the 1950s, but the concept of maintaining live cell lines separated from their original tissue source was discovered in the 19th century.

--From wikipedia

Our products(such as cell culture dishes) are mostly for cell culture applications, review the category list below and click on a selection for product lists:

-- 35mm Cell Culture Dish

-- 60mm Cell Culture Dish

-- 100mm Cell Culture Dish

-- 35mm Glass Bottom Culture Dish

Compared with the other well known international brands, Biousing cell culture products have the following Advantages.

1. Smoothness

The smoothness of Biousing cell culture dish is as good as the best-selling brands. On the side wall there are three biousing brands.

2. Quality inspection report

We offer batch per batch quality inspection reports that can be accessed by email to info@biousing-inc.com.

3. GMP standard management

We emulate the management of pharmaceutical company to supervise the whole production process. A QA/QC system with SOPs and standard documentation management guarantees the quality of biousing products to the international standard.

Introduction of 96 Well ELISA Plate

2008-06-06T10:52:46+02:00

p>A Microtiter plate (spelt Microtitre in Europe) or microplate is a flat plate with multiple "wells" used as small test tubes. The microplate has become a standard tool in analytical research and clinical diagnostic testing laboratories. A very common usage is in the enzyme-linked immunosorbent assay (ELISA), the basis of most modern medical diagnostic testing in humans and animals. A microplate typically has 6, 24, 96, 384 or even 1536 sample wells arranged in a 2:3 rectangular matrix. -- from Wikipedia

Biousing Biotechnology Co., Ltd. is a professional biology hi-tech company that is focused on research, manufacturing and sales of high-level laboratory consumables, devices and reagents. Their featured ELISA produt is 96 well ELISA plate.

Features of 96 well ELISA plate:

Produced conform to the SBS-3d-standard exhibit finest workmanship. The binding capacity is 400-500ng/ cm2, CV<4%.

The bottom thickness of biousing 96 well cell culture plates are carefully lessened. This change assures less edge effect because the temperature will reach uniform faster.

The absolutely flat floor area, free from inclusions, guarantees the highest level of transparency. The detection background is lower than that of the other international brands.

The smoothness of Biousing cell culture plates is much better than the best-selling brands. This will greatly eliminate the system error when 96-well plates are used in ELISA.

The Usage of Glass Bottom Cell Culture Dishes

2008-06-06T10:49:39+02:00

How are glass bottom cell culture dishes typically used?

1. Maintain sterility: Open dishes in a sterile environment (e.g. laminar flow hood).

2. Pre-equilibrate dishes: Incubate the dishes with culture medium. Pipet 2-3 ml of medium into the 35 mm glass bottom cell culture dishes or 3-4 ml into the 50 mm glass bottom cell culture dishes and incubate at 37° C for 15 minutes.

3. Add cell suspension to microwell: Remove the culture medium by aspiration and plate cells onto the glass surface. Pipet 250μl of the cell suspension (cells suspended in culture medium) into the 10 mm diameter microwells or 500μl of cell suspension into the 14 mm microwells. Incubate the dishes for 1 hour at 37° C.

4. Add additional medium: After 1 hour, gently fill the remainder of the dish with medium Add 2-3 ml to the 35 mm glass bottom cell culture dishes or 3-4 ml for the 50 mm glass bottom cell culture dishes. Note: After the initial one hour period to allow cells to attach to the glass surface, it is important to fill the dish to normal levels in order to minimize the effects of evaporation and to avoid inducing changes in osmolarity.

Biousing 35mm Glass Bottom Cell Culture Dishes Product Features:

Glass bottom dishes have a thin and optically clear bottom. A clinically non-toxic adhesive is used to attach the cover glass to the bottom of the TC treated culture dish. Round cover glass is used to make this product more elaborate.

Silver jewelry wear rules

2008-06-05T04:31:55+02:00

Silver jewelry is a special thing in your daily life. You should find the best way to wear it. Maybe you are very puzzled how to choose a silver jewelry for your cloth. Now there are some rules can help you.

1. Professional clothes should come together with simple\ fine style silver necklace.

2. Leisure clothes should come together with special\ exaggerate style silver necklace.

3. Lovely clothes can come toether with silver bracelet with a little bell. It will let you very happy and lovely.

4. Silver jewelry with colorful man-made stone should go together with young girl.

5. Tibet silver jewelry must not go together with gold\golden jewelry. But different style silver jewelry can wear at the same time.

6. Tibet silver jewelry must not to together with professional cloth. It will let others think you are not professional person.

7. When you attend party or wear the gorgeous dress, you should come together with silver jewelry with diamond or other gem.

8. Silver jewelry will be oxidized and some part will turn to black. Please don't worry about it will affect you image. It looks like retro style. It's another sense of silver jewelry.

9. Silver jewelry belong to fashion things. Please prepare more styles in order to change to wear.

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Tiffany fashion jewelry purchase common sense

2008-06-04T12:05:18+02:00

Tiffany glow with the design of the exquisite dazzling or calm restrained, so that you can feel the culture of Tiffany brand, so the classification is very particular about brands, we can be grading on the main distinction between them and, according to our own demand to choose Tiffany jewelry.

Grade introduced: the hierarchy generally consists TIFFANY: real goods, Genuine; A+, a level; b level; other.

Real Goods is legitimate tiffany store with the sale of the real goods TIFFANY single laboratory;

Genuine refers to the original manufacturer TIFFANY store Availability production mode, and compared the lack of real goods single laboratory report, which is mainly used to export; and real goods Comparatively speaking, the general lack of laboratory report only single, with silver in 92.5 percent above.

A+ international best-selling refers to the TIFFANY products, the price is not high, but production steps, as well as the appearance of the final product are close to authentic.Not necessarily amount of silver up to standard, for the worship of Silver friends not too high, the proposed buy this. Fact to the high volume of silver really unnecessary and people could not see. Suggest that you buy this just general.

A level: bits is a poor place, with an average volume of silver lower number, such as: Will many of the "bread silver" ornaments (this does not ring for the beautiful, But long-time will not change color), in the process of making requests not stringent enough, such as polishing, laser logo, but it is not enough stringent checks, there defective rate is relatively high, the surface may not be entirely smooth, Cheaper prices.

B level refers to some small factories or workshops own family production of the so-called TIFFANY, of course, due to various reasons, the overall quality and quantity of silver have caught up with the front, and some quality really is not bad, but the majority are very difficult to say. If you are luck ,you can and may buy a similar, but in most cases can only feel a loss:)

Genuine: It is now the international market is the most commodity-like tiffany goods, TIFFANY Genuine can buy only a few major cities where the franchise, if scores can buy authentic pieces are deceptive, because not a few hundred pieces of authentic.

A+ goods: This is the best imitation goods, as Tiffany processing requirements for the silver decoration very high, so do the grading here a total of only 30 companies (That we are selling is the one), even as some businesses real goods sold. With its quality is Commodities without distinction, in full accordance with tiffany shape 1:1 manufacturing, materials identical polishing beautifully TIFFANY Lettering, 925 silver signs Fine.

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How to Choose The Right Bracelet

2008-06-04T09:02:12+02:00

In this article we explain how to choose the right bracelet. Your bracelet could be made in silver or gold, it could be a simple bracelet or be studded with stones and diamonds. Make sure that you know how to evaluate a good bracelet.

Step One

Basic Design: The first thing that you should consider is the basic design of the bracelet. The design should be streamlined without sharp or pointed edges. Sharp edges can not only injure delicate skin, but also get bent or dented easily. The type of mounting used for the diamonds and gemstones in your bracelet will depend on the design. Prongs used to mount gems need to be sturdy and strong. If the gemstones in your bracelet are mounted with thin needle-like prongs, the prongs can get caught in pockets and other places. This causes the prongs to gradually open up, this ofcourse loosens the gemstones which can then drop off. The design dimensions for your bracelet should take the metal weight into consideration. A wide width with low gold or silver weight, will mean that the metal is too thin. This can cause your bracelet to lose shape and get damaged.

Step Two

Metal Weight: The metal weight of the bracelet is another important thing to be checked. Good mounting of the gemstones or diamonds in your bracelet will need sufficient gold or silver weight. There can be no standard weight suitable for all bracelets, much will depend on the design, the number of gems and diamonds, the length and width of the bracelet etc. Looks can be deceptive so pay special attention to the weight of your bracelet. In general you can be sure that, ladies bracelets with a metal weight that is less than 10 grams will not be durable and sturdy. Your jeweller might tell you that, healthy metal weight will make your bracelet appear clumsy and bulky. Stop believing this nonsense, the truth is that the design needs to ensure that the bracelet does not appear bulky. The design for your bracelet should have good metal thickness, this will not be visible from the front of the bracelet. Compromising on the gold or silver weight of your bracelet would also mean that, the links that connect the segments of the bracelet will be weak. This can cause the bracelet to snap, it could then easily fall off your wrist and get lost. So remember that, good metal weight is essential for gold or silver bracelets.

Step Three

Gemstone Options:You should also be given a wide range of gemstone options to select for your bracelet. Many jewellers use whatever few gemstones they have and put a bracelet together. This does not work to your advantage as you are restricted in your choice. You could choose the gemstones in your bracelet based on color, type, birthstone or traditional beliefs. For example, a mother's bracelet could include the birthstone of the mother and all her children. Such family birthstone bracelets can be made only if a wide choice of gems is available. There is ofcourse the issue of budget that you have at your disposal. You might see a gorgeous sapphire bracelet but, the sapphires could drive the bracelet out of your budget. You should be allowed to choose the same bracelet with cheaper gems like, blue topaz, iolite or probably cheaper sapphires. A jeweller with limited access to gems and production facilities will restrict your choice too. There is also the issue of conditions in which your bracelet would be worn. For example, an emerald bracelet needs special care when wearing and storing, this is because of the nature of emeralds. You might pefer the same bracelet design with green tourmaline instead of emeralds. Your jeweller will need to satisfy your requirements and not the other way round.

Step Four

Choose The Metal: The metal for your bracelet will be a component of the price tag, a gold bracelet would add a substantial amount to the price tag. You should therefore have the option to choose gold or silver for your bracelet. Most jewellers are very eager to sell gold bracelets, but will either ignore you are provide you with second grade service if you talk about a silver bracelet. This is sad but true, so look for a jeweller who is willing to make a good quality silver bracelet for you if that is what you want. It is often said and rightly that, a good quality silver bracelet is better than a delicate and light weight gold bracelet. When you choose your silver bracelet remember that, no compromises regarding gemstone choice or craftsmanship need be made. For gold bracelets, you should have the option to select a 14k or 18k bracelet and also choose the gold color. If you are looking for a white gold bracelet, there is no reason why you should be happy with a yellow gold aquamarine bracelet. Jewellers make gold bracelets with low weight, this is done to allow lower price tags. They really don't care what problems these light weight junk will cause you after the payment has been made.

Step Five

Good Craftsmanship: Insist on good craftsmanship for your bracelet, this should be the case for gold or silver bracelets. Bad craftsmanship could also mean loose gemstones and badly connected links. It is true that mass produced bracelets cannot be given individual attention. This is the reason why a custom bracelet could be best for you. Good craftsmanship is essential for ladies and men's bracelets, make sure that your bracelet is well crafted. Good craftsmanship provides more than just good appearance for your bracelet, this will clearly work to your advantage in the longterm.

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The Meaning of Rings and Fingers

2008-06-02T09:27:00+02:00

Rings are circles. In all cultures the circle is a symbol of unity and eternity, encompassing all. In early cultures, rings were considered magical or sacred through their association with the sun, moon and gods, thus giving protection to the wearer by binding one with power and energy.

Some of the magical mythology of ancient times still influences how and why we wear rings. Kings, priests and healers wore rings on the index finger because that finger was thought to be especially powerful. Medicines were applied to the body with the index finger to give speed and power to their effect. Even today, wearers of healing gemstones wear the rings on the index finger to take the best advantage of the curing energies.

The strongest magical tradition that still holds fast today is the one about the third or ring finger. The ring finger was thought to contain a nerve that went directly to the heart. Wearing a wedding or engagement ring on the ring finger still symbolizes the binding commitment and union of hearts. The Meaning of Fingers When Wearing Rings:

Right Hand vs. Left Hand

In the dual nature of man, the right and left hands are part of his whole being yet represent his twofold conscious and subconscious mind. The left hand (the subconscious) is a reflection of his deeply buried instinct, beliefs and attitudes. The right hand (the conscious) reflects his logic and his awareness. Wearing rings on your left hand could symbolize your unknowing wish to strengthen the powers associated with the finger that wears the ring. Rings on the right hand reflect your desire to control your life and actions.

The Thumb: Will Power

The thumb represents the self. Set apart from other fingers but working in unison with them to give strength to the hand that the others cannot, the thumb symbolized our self in our world. It is associated with logic and will power which govern our actions. Rings on the thumb symbolize freedom and independence of thought and action.

The Index Finger: Authority & Ambition

This finger reflects our need to enhance our ego. The forefinger, throughout history, has represented authority and power. It is associated with leadership and ambition. Kings, priests and healers wore rings on the index finger because that finger was thought to be especially powerful. Nowadays, people wear rings on the index finger as a show of assertiveness.

The Middle Finger: Identity & Materialism

The middle finger is associated with our role in life. Being in the center of the hand, it symbolizes personal identity and those things that are at central to our world. Those wearing rings on the middle fingers are well balanced yet wish to be at the center of attention.

The Ring Finger: Emotion & Creativity

The third finger is associated with affections because it is the one with a direct connection to the heart. It also represents our creativity and artistic self. A wedding or engagement ring on this finger proclaims to the world that the wearer emotions and creative goals are committed to the giver of the ring. If the ring is acquired by the wearer instead of a mate, it symbolizes self worth and a commitment to one personal skills and talents.

Little Finger: Relationships

The little finger is at the opposite end from the thumb. While the thumb symbolizes the inner self, the little finger is associated with others outside of ourselves. It sits on the outside of our hands, facing the world. It is the relationship finger, expressing our attitudes towards other people, sex, and the material world. Rings on the little finger represent confidence and independence in personal and business relationships. Rings here can also express a person attitude about sexuality and how appealing they consider themselves to be.

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Cisco CCIE Routing and Switching Written 350-001 Exam

2008-05-31T03:17:39+02:00

CCIE Routing and Switching Written Exam 350-001 is a two-hour, multiple choice test with 100 questions covering Routing and Switching networking theory related to topics such as IP, IP routing, non-IP desktop protocols, bridging and switch-related technologies, and includes some equipment commands. The 350-001 exam is closed book and no outside reference materials are allowed.

Beta Exams

Each written exam version is offered first in beta form at a discounted cost of US$50. Beta exams are scheduled as you would other written exams and are available at all worldwide testing locations. A passing grade on the beta qualifies a candidate to schedule the lab exam. Results, however, are typically not available until six to eight weeks after the close of the beta. A candidate may attempt the beta exam only once during the beta period.

Cost

Written exams are administered by independent vendors at cost of US$315. Costs may vary due to exchange rates and local taxes (VAT, GST).

Expiration

Candidates must make an initial attempt of the CCIE lab exam(350-018 Lab and 350-001 Lab) within 18 months of passing the CCIE written exam. Valid passing scores on written exams expire after 18 months.

Locations

Written exams are taken at any worldwide VUE testing facility. See their websites for more details.

Results

Written exam results are Pass/Fail and are available immediately following the exam. The passing score is set by statistical analysis and is subject to periodic change.

Retakes

Candidates must wait five days between attempts at the written exam. Once a candidate has passed the exam, he or she may not take the same exam again (for recertification purposes) for at least 180 days.

Infomation from http://www.cisco.com/web/learning/le3/ccie/rs/written_exam.html

Preparing for the 350-001 exam? Searching 350-001 Test Questions, 350-001 Practice Exam, 350-001 Dumps?

Exam4sure 350-001 is written to coincide with the real test by the experienced IT experts and specialists. With the complete collection of Questions and Answers, Exam4sure 350-001 is high enough to help the candidates to pass this exam easily without any other study materials and no need to attend the expensive training class.

How to pass CCNA 6 Steps to Success

2008-05-30T04:43:31+02:00

CCNA is one of the most respected Associate level Certification in the world today.

Getting a CCNA will definitely help you to get a better job or at least get your foot into Professional Networking Field. When you meet a person that has CCNA degree you will notice that he or she knows something about Networking.

This article will describe and give you some tips on how to achieve CCNA.

I did it so can you, so lets get started.

1. Getting ready mentally

First thing you need to do is mentally prepare your self. What I mean by that is that you have to seriously think about on why are you getting CCNA and why do you want to be CCNA certified. You have to firmly decide and believe that you will get CCNA within next 3-6 months or so.

Try to budget your study time well. If you a very social person (like me) you will have to give up some of your social time for the next couple of months.

Your friends and family will understand. Trust me: it is well worth it. Once you get that cert you can make up for the lost social time.

2. Getting the right study material

Second thing you need to do is to get proper study material.

There is lot of controversy around this and some people go overboard with study guides, books, simulators and such.

I believe that two Cisco Press books INTR and ICND by Wendell Odom are enough as far as the books go. They are really well written and easy to follow. So sign up at http://www.ciscopress.com and get those two books. Make sure you got the latest version.

You will also want to get some kind of a simulator that will let you practice commands and that will also build up your confidence.

You can buy real equipment but that could get expensive. I highly recommend that you become member of Cisco Certification forum.

Forum is huge and you will get lot of helpful answers, tips and advices pretty quick. (I know I did)

3. Approach and diving deep

There are many different approaches to studying from books but I will tell you about mine. This step will take the most of your studying time.

- Before you even start reading any of the books I suggest learning binary math (really easy) and subnetting so you can do it in your sleep.

- Read both books casually once from front to cover (make sure you cover introduction and practice questions too). This will give you good overview.

- Install both CD’s that came with books and practices some of the questions. Don’t worry if you get lot of them wrong.

- Now, you will ready both books again but this time you will have to read it to truly understand the concept and how things work. Master one chapter and do questions from just that chapter until you sick of it. Then move to the next chapter.

- Once you mastered all chapters do lot of questions and labexercises. Those two CD’s will give you ability to do that.

4. Schedule the test

You’re not done yet with studying but it is really good to schedule the test after you completed step 3 in this article. Here is why:

If you schedule the test a month in advance right after you completed step 3, you won’t be able to slack and make excuses not to study hard until tests and it is also good to give your self a headline. I have seen people working on their CCNA for 2 years. They master one or two chapters, then they rest for 2 two months and right when they think they are ready for the next chapter, they forget what they have learned in the first chapter.

5. Read both books one more time to refresh

This is optional, but I highly recommend reading the both books one more time. If you read both books in a three week that will give you one more week before the test to cram which is subject of the next step.
So by now you should’ve read both books three times over. I also suggest re-reading questions and answers from both books one more time.

6. Cram, Cram and Cram

- This is the last part of your study and there is no turning back.

Deadline is hanging around your neck like a noose. You should cram Q&A for no more then 10 days before you take the test.

At this point it is really important that you get fresh and different questions then those included with your CD’s. Some people claims that brain dumps or Q&A are bad and evil. I tend to disagree with that. At this point you already firmly grasped the whole CCNA concept and Q&A will only help you. So get some Q&A exam question and cram, cram and cram them for a week.

- Don’t use books or CD’s anymore.

There is no looking back. No worries, material from the books will return to you at the right time.

- Don’t do any studying a night or a day before the test.

Go out with your wife or significant other to a dinner and a movie. Relax. It is very important to relax and get a good night sleep since one of those testing boots could really be intimidating. If you did all the steps above and read books with intention to understand the topics and how stuff works (no pun intended), and not just to pass the test you should be more then ready by now.

We came to an end of this short tutorial. I hope this article give you at least some ideas on how to approach studying for CCNA.

If you fail CCNA first time, don’t get discouraged. You will have more knowledge and confidence when you attempt it the next time then the person who passed it on the first try. Whatever approach you take I wish you good luck and prosper career.

CCNA exams list: 640-802, 640-816, 640-822, 640-811, 640-821.

About the Author:

Vanja Buric is Network Engineer, and works for Charter Communication Business Engineering Department,
and also owner of the http://www.vanjaburic.com website, where you can get latest networking news, articles,tips, free e-Books, virus alerts and lot more… as well as purchase IT Exam study guides.