ATLANTA, Georgia (CNN) – Most of us have them — the personal ritual to deal with the “ick” of a public bathroom: wiping the seat with toilet paper, using a paper seat cover or even rolling up several pieces of toilet paper to create a thicker barrier between the skin and … the unknown.
But the toilet seat is actually the cleanest part of the bathroom, one expert says.
Charles Gerba, a microbiologist at the University of Arizona who has studied restrooms and other germ-infested environments for more than 20 years, says that because of the care people take when they’re about to sit, other parts of the bathroom are much more prone to delivering bacterial infections.
“One of the cleanest things in the bathrooms we find are the toilet seats,” Gerba said. “I’d put my fanny on it any time — unless it’s wet; then you’d want to wipe it first.” Avoiding bathroom ‘hot spots’ »
The Internet has come through for people who just want a clean place to go. New tools like MizPee (nationwide) and Diaroogle (New York only) will point you to the nearest public restroom and display extensive comments about those facilities from users, even delivering the information to your mobile phone. (Warning: CNN makes no promises about the cleanliness of the language in these bathroom locators.)
MizPee launched a year ago for people in San Francisco, California, after co-founder Peter Olfe saw that the city’s public library bathroom was “so disgusting,” said Dhana Pawar, vice president and co-founder of Yojo Mobile, which created MizPee. “Unfortunately, [MizPee] was inspired by that trip.”
Fueled by demand, MizPee has expanded to more than 22 cities in America and six in Europe, and has had more than 300,000 unique visitors. Users rate toilets on a scale from one to five toilet paper rolls and nominate the best and worst toilets for the Flush of the Year award. The site also gives users information on deals at restaurants, shops and services nearby, in addition to toilet trivia called “looisms.”
Women tend to have higher standards for bathroom cleanliness than men, often rating any given unisex bathroom lower than men, Pawar said. In general, many more women than men use the site, but male bikers and older men, especially colitis patients, also come to MizPee.
Women are also particularly concerned about finding clean bathrooms with changing stations, Pawar said. “You’d be surprised how few there are.”
Pawar said she herself is “really paranoid” when it comes to the restroom.
“I’m one of those really anal people who have to have a clean bathroom,” she said.
For many people, public bathrooms generate feelings of anxiety, fear and disgust.
“Basically, everybody is fearful of public restrooms,” said Dr. Lisa Bernstein, assistant professor at Emory University School of Medicine, who admitted that her mother always told her that she should never make direct contact with a toilet seat.
Research indicates that fear of the commode itself may be misdirected.
Public bathrooms may contain several kinds of harmful bacteria, including E. coli, salmonella, coliform, rotavirus, cold virus and the potentially deadly form of staph known as MRSA, experts say. But people are more likely to pick up these nasty bugs through touching things in the bathroom with their hands, not their behinds.
“I don’t think anyone would voluntarily sit on a seat with urine, but, in reality, urine touching intact skin on the tush won’t do anything,” Bernstein said.
More concerning, however, is a child who steadies himself or herself on a toilet seat by holding onto it and then leaving without washing hands, she said. Those germs could lead to an infection once the child’s hands touch the nose, mouth or eyes.
And don’t forget that unwashed hands have handled everything from the door knob to the lock to the flusher. Again, if you touch one of these objects and then rub your eye, nose or mouth, you’re apt to transmit that bacteria.
But there is hope. Here are hygiene helpers:
Wash your hands
Yes, it’s basic. But, in general, washing your hands is the most effective action you can take to prevent bacterial infections from a public bathroom, experts say.
“You can remove all gastrointestinal and respiratory infection bacteria by washing hands,” said Judy Daly, clinical microbiologist at the University of Utah and spokesperson for the Clean Hands Campaign. “Seventeen seconds of a little bit of friction, water and soap will really mediate bacteria.”
The American Society for Microbiology, which sponsors the Clean Hands Campaign, found in a study last year that about 77 percent of men and women washed their hands in public restrooms, down 6 percent from 2005. The observational study also found that women washed their hands more than men.
“It’s such an easy intervention,” Daly said. “If you get it to be a habit for a 30-day period, it’s something you do automatically.”
Use automatic devices
Recent bathroom additions like automatic hands-free faucets and paper towel dispensers diminish contact between your hands and bathroom items that may bear bacteria, Bernstein said.
Don’t let your belongings touch the floor
Gerba’s research found that the highest concentration of germs in a public bathroom are on the floor, the outside of the sanitary napkin disposal and the sink and water taps.
When Gerba looked at women’s purses, he found that one-third of them had fecal bacteria on the bottom. Make sure you hang your shoulder bag on a hook. If none is available, some people swear by hanging the strap around their necks.
Use the first stall
The middle stall of a public restroom usually has the most bacteria because people use it the most. “I guess people like company,” Gerba said. The first stall will probably be cleaner.
Recognize the best and the worst
As a rule, the cleanest toilets are usually in hospitals, because they use disinfectants heavily, but the worst are in airports and airplanes, Gerba said. The small size of airplane bathrooms, including the sinks themselves, make it hard for people to wash their hands — in fact, Gerba’s study found a thin layer of E. coli in an airplane bathroom.
As for the airports themselves, “In the men’s room at Chicago O’Hare, I don’t think the toilet seat ever gets cold,” Gerba said.
Don’t hold back
It’s fine for a woman to hover over the toilet seat if she doesn’t want to sit down, but if she doesn’t empty her bladder completely, she’s at risk for a urinary infection, Bernstein said.
“You may be doing yourself more harm than good,” she said.
Along the same lines, you can develop urinary infections from “holding it in” too long just because you don’t want to use a particular facility. Better in a public stall than not at all.
Put it in perspective
Although the bathroom seems like a nasty place, the possible infections from the dreaded stall are no different from the ones you can get anywhere else in public.
“They’re the same bugs we transmit shaking hands,” Bernstein said. “People are more freaked out about restrooms, but the same thing applies anywhere in public.”
After all that research — he’s had the cops called on him while prowling around bathroom floors — Gerba has no problem with sitting down on public toilets. But Bernstein still uses one or two seat covers, “because of what my mother taught me,” she said.
By Elizabeth Landau
CNN
Monday, October 13, 2008
Sunday, October 12, 2008
Saturday, October 11, 2008
The Peacock Flowers of Lavasa
But beauty seen is never lost,
God’s colors all are fast;
The glory of this sunset heaven
Into my soul has passed…..
-John Greenleaf Whittier, Sunset on the Bearcamp, 1876
It had been quite a while since I visited Lavasa. I was looking forward to smell the red earth again. This red earth has a fragrance different from any other part of India. I was missing my home in the mountains. As soon as I crossed the Lavasa Dwaar, I noticed the colors. There were flowers starting to bloom in the Mose valley. We were greeted with red gladioli in the newly laid out picturesque flower-beds!
Come experience the vibrant waves of color that have started covering the hillsides at Lavasa. This wonderful display of horticultural beauty surprised me and promises to welcome us into a sea of floral color and aromatic delights. The gardeners have been busy in the monsoons and their results are just showing. I must have gone up and down the slopes from Ekaant to Portofino more than a 50 times but this time was surprised with the vibrant peacock flowers of Lavasa - I stopped and walked in the sloping hill-side gardens for hours. It was a stunning day, beautiful sunshine, so the flowers were open and could be enjoyed. I had noticed a few flower-beds coming up on the hill slopes especially at vantage viewing areas after the Lavasa-Dwaar but these Peacock Flowers of Lavasa are something different. They have changed the blue and green Lavasa landscape to red and yellow sprinkled all over the green countryscape. My wife was the flower-expert this time and instantly diagnosed the flower-fields to be Caesalpinia Pulcherrima (I was impressed with a gynecologist identifying the flower type spot-on!).
In the genus Caesalpinia the most popularly planted species is Caesalpinia pulcherrima. Common names for this species include Poinciana, Peacock Flower, Red Bird of Paradise, Mexican Bird of Paradise, Dwarf Poinciana, Pride of Barbados, and flamboyan-de-jardin. It is a shrub growing to 3 m tall, native to tropical America. The leaves are bipinnate, 20-40 cm long, bearing 3-10 pairs of pinnae, each with 6-10 pairs of leaflets 15-25 mm long and 10-15 mm broad. The flowers are borne in racemes up to 20 cm long, each flower with five yellow, orange or red petals. The fruit is a pod 6-12 cm long. It is a striking ornamental plant, widely grown in tropical gardens. It is also the national flower of the Caribbean island of Barbados, and is depicted on the Queen's personal Barbadian flag. In India it is found in the tropical rain forests. With a beautiful inflorescence in yellow, red and orange, it is called "Ratnagundhi" colloquially.
Medicine men in the Amazon Rainforest have long known some of the medicinal uses for Caesalpinia pulcherrima, which is known as ayoowiri. The juice from the leaves is said to cure fever, the juice from the flower cures sores, and the seeds cure bad cough, breathing difficulty, and chest pain. Four grams from the root is also said to induce abortion in the first trimester of pregnancy.
Word lover that I am, I searched for the translation of Caesalpinia Pulcherrima, figuring it meant something like "the most beautiful king of plants" (since I know from Akeela and the Bee that pulcher is Latin for beauty, and I figured Caes... meant "king" like Caesar). What I found out is that Caesalpinia was named after Andrea Cesalpino (1519--1603), an Italian botanist (citation). And Pulcherrima, as I guessed, means "most beautiful."
And the playground of Poseidon still looks best at Dusk(see picture). Dusk refers to the period of time following sunset. Although commonly confused with twilight, dusk is the time frame that occurs either before or after a twilight - when the sky is still generally bright and blue, but there is no sun to accompany it.
Twilight, again. Another ending. No matter how perfect the day is, it always has to end.
Stephenie Meyer, Twilight, 2005
Friday, October 10, 2008
Thursday, October 9, 2008
Applications of PCR
The Polymerase Chain Reaction (PCR) has found widespread application in many areas of genetic analysis. This is a list of some of these applications:
1 Medical applications
2 Infectious disease applications
3 Forensic applications
4 Research applications
Medical applications
PCR has been applied to a large number of medical procedures:
The first application of PCR was for genetic testing, where a sample of DNA is analyzed for the presence of genetic disease mutations. Prospective parents can be tested for being genetic carriers, or their children might be tested for actually being affected by a disease. DNA samples for Prenatal testing can be obtained by amniocentesis, chorionic villus sampling, or even by the analysis of rare fetal cells circulating in the mother's bloodstream. PCR analysis is also essential to Preimplantation genetic diagnosis, where individual cells of a developing embryo are tested for mutations.
PCR can also be used as part of a sensitive test for tissue typing, vital to organ transplantation. As of 2008, there is even a proposal to replace the traditional antibody-based tests for blood type with PCR-based tests.
Many forms of cancer involve alterations to oncogenes. By using PCR-based tests to study these mutations, therapy regimens can sometimes be individually customized to a patient.
Infectious disease applications
Characterization and detection of infectious disease organisms have been revolutionized by PCR:
The Human Immunodeficiency Virus (or HIV), responsible for AIDS, is a difficult target to find and eradicate. The earliest tests for infection relied on the presence of antibodies to the virus circulating in the bloodstream. However, antibodies don't appear until many weeks after infection, maternal antibodies mask the infection of a newborn, and therapeutic agents to fight the infection don't affect the antibodies. PCR tests have been developed that can detect as little as one viral genome among the DNA of over 50,000 host cells . Infections can be detected earlier, donated blood can be screened directly for the virus, newborns can be immediately tested for infection, and the effects of antiviral treatments can be quantified.
Some disease organisms, such as that for Tuberculosis, are difficult to sample from patients and slow to be grown in the laboratory. PCR-based tests have allowed detection of small numbers of disease organisms (both live or dead), in convenient samples. Detailed genetic analysis can also be used to detect antibiotic resistance, allowing immediate and effective therapy. The effects of therapy can also be immediately evaluated.
The spread of a disease organism through populations of domestic or wild animals can be monitored by PCR testing. In many cases, the appearance of new virulent sub-types can be detected and monitored. The sub-types of an organism that were responsible for earlier epidemics can also be determined by PCR analysis.
Forensic applications
The development of PCR-based genetic (or DNA) fingerprinting protocols has seen widespread application in forensics:
In its most discriminating form, Genetic fingerprinting can uniquely discriminate any one person from the entire population of the world. Minute samples of DNA can be isolated from a crime scene, and compared to that from suspects, or from a DNA database of earlier evidence or convicts. Simpler versions of these tests are often used to rapidly rule out suspects during a criminal investigation. Evidence from decades-old crimes can be tested, confirming or exonerating the people originally convicted.
Less discriminating forms of DNA fingerprinting can help in Parental testing, where an individual is matched with their close relatives. DNA from unidentified human remains can be tested, and compared with that from possible parents, siblings, or children. Similar testing can be used to confirm the biological parents of an adopted (or kidnapped) child. The actual biological father of a newborn can also be confirmed (or ruled out).
[edit]Research applications
PCR has been applied to many areas of research in molecular genetics:
PCR allows rapid production of short pieces of DNA, even when nothing more than the sequence of the two primers is known. This ability of PCR augments many methods, such as generating hybridization probes for Southern or northern blot hybridization. PCR supplies these techniques with large amounts of pure DNA, sometimes as a single strand, enabling analysis even from very small amounts of starting material.
The task of DNA sequencing can also be assisted by PCR. Known segments of DNA can easily be produced from a patient with a genetic disease mutation. Modifications to the amplification technique can extract segments from a completely unknown genome, or can generate just a single strand of an area of interest.
PCR has numerous applications to the more traditional process of DNA cloning. It can extract segments for insertion into a vector from a larger genome, which may be only available in small quantities. Using a single set of 'vector primers', it can also analyze or extract fragments that have already been inserted into vectors. Some alterations to the PCR protocol can generate mutations (general or site-directed) of an inserted fragment.
Sequence-tagged sites is a process where PCR is used as an indicator that a particular segment of a genome is present in a particular clone. The Human Genome Project found this application vital to mapping the cosmid clones they were sequencing, and to coordinating the results from different laboratories.
An exciting application of PCR is the phylogenic analysis of DNA from ancient sources, such as that found in the recovered bones of Neanderthals, or from frozen tissues of Mammoths. In some cases the highly degraded DNA from these sources might be reassembled during the early stages of amplification.
A common application of PCR is the study of patterns of gene expression. Tissues (or even individual cells) can be analyzed at different stages to see which genes have become active, or which have been switched off. This application can also use Q-PCR to quantitate the actual levels of expression.
The ability of PCR to simultaneously amplify several loci from individual sperm has greatly enhanced the more traditional task of genetic mapping by studying chromosomal crossovers after meiosis. Rare crossover events between very close loci have been directly observed by analyzing thousands of individual sperms. Similarly, unusual deletions, insertions, translocations, or inversions can be analyzed, all without having to wait (or pay for) the long and laborious processes of fertilization, embryogenesis, etc.
1 Medical applications
2 Infectious disease applications
3 Forensic applications
4 Research applications
Medical applications
PCR has been applied to a large number of medical procedures:
The first application of PCR was for genetic testing, where a sample of DNA is analyzed for the presence of genetic disease mutations. Prospective parents can be tested for being genetic carriers, or their children might be tested for actually being affected by a disease. DNA samples for Prenatal testing can be obtained by amniocentesis, chorionic villus sampling, or even by the analysis of rare fetal cells circulating in the mother's bloodstream. PCR analysis is also essential to Preimplantation genetic diagnosis, where individual cells of a developing embryo are tested for mutations.
PCR can also be used as part of a sensitive test for tissue typing, vital to organ transplantation. As of 2008, there is even a proposal to replace the traditional antibody-based tests for blood type with PCR-based tests.
Many forms of cancer involve alterations to oncogenes. By using PCR-based tests to study these mutations, therapy regimens can sometimes be individually customized to a patient.
Infectious disease applications
Characterization and detection of infectious disease organisms have been revolutionized by PCR:
The Human Immunodeficiency Virus (or HIV), responsible for AIDS, is a difficult target to find and eradicate. The earliest tests for infection relied on the presence of antibodies to the virus circulating in the bloodstream. However, antibodies don't appear until many weeks after infection, maternal antibodies mask the infection of a newborn, and therapeutic agents to fight the infection don't affect the antibodies. PCR tests have been developed that can detect as little as one viral genome among the DNA of over 50,000 host cells . Infections can be detected earlier, donated blood can be screened directly for the virus, newborns can be immediately tested for infection, and the effects of antiviral treatments can be quantified.
Some disease organisms, such as that for Tuberculosis, are difficult to sample from patients and slow to be grown in the laboratory. PCR-based tests have allowed detection of small numbers of disease organisms (both live or dead), in convenient samples. Detailed genetic analysis can also be used to detect antibiotic resistance, allowing immediate and effective therapy. The effects of therapy can also be immediately evaluated.
The spread of a disease organism through populations of domestic or wild animals can be monitored by PCR testing. In many cases, the appearance of new virulent sub-types can be detected and monitored. The sub-types of an organism that were responsible for earlier epidemics can also be determined by PCR analysis.
Forensic applications
The development of PCR-based genetic (or DNA) fingerprinting protocols has seen widespread application in forensics:
In its most discriminating form, Genetic fingerprinting can uniquely discriminate any one person from the entire population of the world. Minute samples of DNA can be isolated from a crime scene, and compared to that from suspects, or from a DNA database of earlier evidence or convicts. Simpler versions of these tests are often used to rapidly rule out suspects during a criminal investigation. Evidence from decades-old crimes can be tested, confirming or exonerating the people originally convicted.
Less discriminating forms of DNA fingerprinting can help in Parental testing, where an individual is matched with their close relatives. DNA from unidentified human remains can be tested, and compared with that from possible parents, siblings, or children. Similar testing can be used to confirm the biological parents of an adopted (or kidnapped) child. The actual biological father of a newborn can also be confirmed (or ruled out).
[edit]Research applications
PCR has been applied to many areas of research in molecular genetics:
PCR allows rapid production of short pieces of DNA, even when nothing more than the sequence of the two primers is known. This ability of PCR augments many methods, such as generating hybridization probes for Southern or northern blot hybridization. PCR supplies these techniques with large amounts of pure DNA, sometimes as a single strand, enabling analysis even from very small amounts of starting material.
The task of DNA sequencing can also be assisted by PCR. Known segments of DNA can easily be produced from a patient with a genetic disease mutation. Modifications to the amplification technique can extract segments from a completely unknown genome, or can generate just a single strand of an area of interest.
PCR has numerous applications to the more traditional process of DNA cloning. It can extract segments for insertion into a vector from a larger genome, which may be only available in small quantities. Using a single set of 'vector primers', it can also analyze or extract fragments that have already been inserted into vectors. Some alterations to the PCR protocol can generate mutations (general or site-directed) of an inserted fragment.
Sequence-tagged sites is a process where PCR is used as an indicator that a particular segment of a genome is present in a particular clone. The Human Genome Project found this application vital to mapping the cosmid clones they were sequencing, and to coordinating the results from different laboratories.
An exciting application of PCR is the phylogenic analysis of DNA from ancient sources, such as that found in the recovered bones of Neanderthals, or from frozen tissues of Mammoths. In some cases the highly degraded DNA from these sources might be reassembled during the early stages of amplification.
A common application of PCR is the study of patterns of gene expression. Tissues (or even individual cells) can be analyzed at different stages to see which genes have become active, or which have been switched off. This application can also use Q-PCR to quantitate the actual levels of expression.
The ability of PCR to simultaneously amplify several loci from individual sperm has greatly enhanced the more traditional task of genetic mapping by studying chromosomal crossovers after meiosis. Rare crossover events between very close loci have been directly observed by analyzing thousands of individual sperms. Similarly, unusual deletions, insertions, translocations, or inversions can be analyzed, all without having to wait (or pay for) the long and laborious processes of fertilization, embryogenesis, etc.
Wednesday, October 8, 2008
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