Study Reveals Parasite-Infected Rodents Attracted To Cat Odor

New research shows how a brain parasite can manipulate rodent fear responses for the parasite's own benefit. The study, authored by Patrick House and Dr. Robert Sapolsky of Stanford University and released this week in PloS One, addressed how the single-celled parasite Toxoplasma gondii makes infected rodents more likely to spend time near cat odors. The study finds Toxoplasma-infected male rats have altered activation in brain regions involved in fear and increased activation of brain regions involved in sexual attraction after exposure to cat odors. The findings may help explain the biological bases of innate fear and sexual attraction.

Toxoplasma requires the cat digestive system for sexual reproduction. Infected rodents, with reduced fear response to cat odors, are presumably more susceptible to predation by cats, thereby enabling completion of the parasite lifecycle. Toxoplasma is manipulating the fear response specifically to the urine of cats -- infected rats behave normally on anxiety, fear, social and memory tasks, and retain fear behavior to non-feline predator odors.


"These findings support the idea that in the rat, Toxoplasma is shifting the emotional salience of the detection of the cat. They also suggest that fear and attraction might lie on the same spectrum, or at least that the emotional processing of fear and attraction are not entirely unrelated," House said.


The study does not advance evidence for how Toxoplasma is altering the brain, only evidence that it does. Previous research showed that Toxoplasma invades the brain of the host and settles near the amygdala, a region involved in a wide range of fear and emotional behaviors. This study extends these findings by showing that not only is Toxoplasma found in the amygdala of infected male rat hosts, but it also changes the way certain subregions of the amygdala respond to cat odor - specifically, by increasing neural activity in the presence of cat odor in regions normally activated by exposure to a female rat.


Up to a third of humans test positive for Toxoplasma, due largely to the consumption of undercooked meat or contact with cat litter. In humans, Toxoplasma exposure is most dangerous to developing fetuses and pregnant women. However, many recent studies find Toxoplasma exposure linked with schizophrenia, a disease noted for amygdala dysfunction and improper emotional response, compelling further investigation into what exactly Toxoplasma is doing in the host brain.


Funding: This work was supported by the National Institutes of Health (5R01 MH079296) and The Stanley Medical Research Institute (06R-1463). The funders had no role in study design, data collection and analysis, decision to publish, or preparation


Competing Interests: The authors have declared that no competing interests exist.


Article References:
House PK, Vyas A, Sapolsky R (2011) Predator Cat Odors Activate Sexual Arousal Pathways in Brains of Toxoplasma gondii Infected Rats. PLoS ONE 6(8): e23277. doi:10.1371/journal.pone.0023277

Scientists Take a Step Towards Developing Better Vaccines for Bluetongue

   Researchers have taken a step towards producing better vaccines against Bluetongue -- an important disease of livestock -- after successfully assembling the virus outside a cell. This research, recently published in the journal Proceedings of the National Academy of Sciences, could provide scientists with the tools to develop vaccines with useful new properties.
Professor Polly Roy of London School of Hygiene and Tropical Medicine, who led the team, explains "We've developed the tools and provided the instruction manual for developing new, more effective Bluetongue vaccines. This will not only be useful for combating Bluetongue but will provide insights into fundamental virus assembly that will be useful for producing vaccines for other viruses."
Better vaccines will be important to help combat the threat that Bluetongue poses to livestock farming in the UK and abroad. Bluetongue is a viral disease of cows and sheep that is transmitted by biting midges. Historically it has mainly affected African farms, but since 1998 the disease has been spreading across Europe. In 2007 one strain of the disease reached as far as the east coast of the UK. The disease is economically devastating and kills up to 70% of the sheep it infects.
Professor Roy continues "Bluetongue is an important virus to study because it poses such a threat to livestock farming, but it presents some considerable scientific challenges. By virus standards Bluetongue is quite architecturally complex and it has a relatively difficult genome to work with, so assembling it in a test tube was a significant challenge. No one had been able to get such a complicated virus to assemble outside a cell before."
Professor Roy and her team synthesised each of the virus's gene and protein building blocks separately and then combined them in the right order in order to produce a functional virus particle. Then, to check whether they had been successful, they infected some midge cells with the newly synthesized virus.
Professor Roy continues "When we injected the virus particles that we had assembled in the test tube into some midge cells they started behaving and replicating just as we would expect a wild virus to do. This was a really exciting moment. What had previously been a complex of proteins and other molecules whirred into activity and started making copies of itself."
Currently, Bluetongue vaccines are produced by chemical treatment of virulent viruses to inactivate them. These vaccines are effective at preventing the disease, but because it is difficult to tell the difference between animals that have been vaccinated from those that have recovered from an infection. This makes controlling outbreaks much more difficult.

 

This new approach provides an assembly kit for the virus which could allow scientists to design vaccines with useful properties. Developing a vaccine that is tagged with a marker, for example, would make it easier to tell the difference between animals that have been vaccinated and those that have suffered the disease.
Professor Douglas Kell, BBSRC Chief Executive, said "This is an exciting development and offers great potential for future vaccine development. Using the tools of synthetic biology, we are now able to assemble viruses piece by piece in a way that gives us far greater understanding of how they work. This approach could allow us to make safer and more effective vaccines against a range of viral diseases.
This research was funded by the Biotechnology and Biological Sciences Research Council (BBSRC).

The 5 most difficult veterinary clients

The 5 most difficult veterinary clients

Every practice has them: clients who inspire you to find a task that needs doing in the back or who trigger a frantic game of rock-paper-scissors to determine who has to deal with them. There's no other way to say it, some clients are just plain difficult. But a difficult client isn't necessarily a detrimental one. Sometimes, those cranky, stubborn, and annoying pet owners who seem like a curse are really gifts in disguise. And sometimes, skillful managing of these clients can transform pain to gain. Here's how to handle them.

Getty Images The Demander A Demander wants nothing but the best for her pet (who no doubt has a delicate constitution and sees the veterinarian on a regular basis for various issues). The Demander asks the doctor a million questions and often uses more than her allotted appointment time. She's on a first-name basis with each team member. If she sees a technician at the grocery store, she corners him with questions. She's been known to call the practice several times a day to give regular reports about her pet's current state of health. Although Demanders are, well, demanding, they're a boon to your practice. The Demander is among your top 20 percent of clients who produce 80 percent of your practice's business—part of the solid core that allows you to keep your doors open. Compliance is never a problem with The Demander. She recognizes and appreciates the value of the services you provide, and her desire to give her pet the best care is an attitude you should admire. As long as her needs are met, The Demander will be one of your biggest fans and will tell others how wonderful you are. How do you handle a Demander? Don't let The Demander take control. Some creative management will allow you to meet her needs while managing your associations with her. Don't be rude if you encounter The Demander outside the practice. Assure her it's great to see her, tell her you want to hear all about her pet, and ask her to call you at the practice. Do schedule additional time with the doctor and charge appropriately. Tell The Demander, "We typically schedule 20-minute appointments but would like to offer an extended appointment to make sure that you have enough time with the doctor to get all your questions answered." If The Demander agrees to this, be sure to mention any additional fees that may apply. Do (patiently) answer each and every one of The Demander's questions. Her intentions are noble. Do encourage The Demander to write down questions at home and bring the list when she comes in for her pet's appointment. This may decrease the number of times she calls your practice with queries, and it reinforces to her your commitment to her pet.

The Cheapskate The Cheapskate wants his dog treated for free. He waits until the end of the visit, after the exam and the radiographs and the lab work, to mention that he doesn't have any money right now. No payment options work for him. He earnestly promises to make payment installments and even signs a financial agreement. But The Cheapskate fails to follow through and is eventually sent to collections. In response, he files bankruptcy. Some time later, The Cheapskate returns to the practice for further treatment, and when he's advised that services can't be rendered without payment, he accuses the staff of being willing to let his pet die. As a client, The Cheapskate is a pain. His promise to pay isn't sincere, and he's unkind to those who refuse him free service. He'll suck your practice dry of energy and finances if you let him. To The Cheapskate, money isn't a problem because he has no intentions of paying in the first place. He'll require firm management to prevent him from taking advantage of your services. How do you handle a Cheapskate? Don't back down by changing your prices. Doing so diminishes the value of the services you provide and could ultimately undermine the practice. Prices are set at levels that allow the practice to stay solvent. Reducing them hurts the bottom line. Don't take attacks personally. The ultimate responsibility for the health and well-being of The Cheapskate's pet lies with The Cheapskate Do repeat yourself. The Cheapskate may need further reinforcement. Ask at the outset of every visit, "What form of payment will you be using today?" Do get The Cheapskate's agreement first. When diagnostics or treatments are needed, make it clear beforehand that payment is due at the time services are rendered. Once the doctor has completed a recommended treatment plan, technicians should review a printed copy with The Cheapskate that includes fees and expectation of payment. Obtain his approval and agreement to pay then proceed with the plan of care.

The Cynic The Cynic just got a new puppy, and things aren't going well. He chews on everything, barks too much, jumps on people all the time—and don't even get The Cynic started on house training! The Cynic has taken his pup to every doctor at the practice, plus a trainer and an animal behavioral consultant. He's been given numerous solutions to his problems but is full of reasons why those suggestions won't work. Although The Cynic is a pain, he can be a gift in disguise. By working straightforwardly with him, you can improve your client communication skills and educational abilities. Handling him may require patience and determination, but he has a problem you can solve. If you stick it out with him and resolve his issues, he'll sing your praises. How do you handle a Cynic? Don't let him believe there's no solution. You're the expert, and you know he's been given solutions that work. Don't continue offering alternatives. This communicates a lack of confidence in the solution he's already been given and indirectly reinforces his "victim" status. Do focus on task specifics. Speak directly to The Cynic, saying, "We know these solutions do work, without exception." Get specific about each situation. Go down a list and address each point, if necessary. Do give your suggestions in writing. Check in with him a few days later to see how things are going and what challenges he's experiencing. Stay solution-oriented and positive. The Cynic will feel your encouragement and have more energy to stick to the suggested program. Do talk frankly about compliance. Make sure he's aware that the responsibility for follow-through is on his shoulders. Let him know that if he does follow through, these methods will work.

The Bully The Bully is just plain mean. No one at the clinic has ever seen him smile. He's rude to the staff and other clients. He's quick to find fault with everything from the time he has to wait for the doctor to the cost of his cat's prescription food. He loudly—and sometimes vulgarly—proclaims his opinion on everything and has zero tolerance for other points of view. There's no denying it: The bully is definitely a pain. Your practice—and everyone in it—is better off without him. How do you handle a Bully? Don't be intimidated. Intimidation is the tool The Bully uses to get his way. Don't play into his hands, and don't cave in to his unfair demands. Don't engage in arguments. You won't change a Bully's mind on most issues, so don't bother trying Don't take his negative communication personally. The Bully treats everyone in a demeaning manner, not just you. Don't buy into his insults. Do be professional. Keep all traces of animosity and antagonism from your voice. Drop your tone of voice. Speak slowly with quiet dignity. Do make The Bully's visit task-focused. Don't give him a chance to push you around—take care of his needs as quickly and efficiently as possible. Do clarify your expectations. Treat The Bully respectfully and demand the same courtesy. Say, "I'm trying to help you with your problem, but when you speak to me so unkindly, I have a hard time staying focused on what's best for Brutus." Do establish a cut-off point. If The Bully won't comply, tell him your practice will no longer be able to provide services for him and his pets.

The Know-It-All The Know-It-All has already diagnosed his pet. He researched the symptoms on the Internet and talked to his neighbor, whose brother-in-law's co-worker's pet had the exact same symptoms. He insists that his cat just needs a simple prescription. The Know-It-All is impatient and annoyed at having to make an appointment, but he makes good use of his time at the clinic—he willingly provides diagnoses for other clients' pets that he encounters in the waiting room. He declines all lab work, because he knows his pet is in good health. Believe it or not, with proper management, The Know-It-All can be a gift to your practice. He wants the best for his pet and has a circle of friends to discuss veterinary care your practice offers. With clear guidelines on your expected client-practice relationship and with The Know-It-All's influential voice in your community, he can be a strong supporter and a source of positive referrals. How do you handle a Know-It-All? Don't let him dictate your practice's standards of medicine. If you give a Know-It-All a prescription and forego an appointment, you're communicating that your medical standards are negotiable. You're also encouraging similar behavior in the future. Don't engage in arguments about his opinions or diagnoses. It's rude (and usually pointless). Don't neglect making important medical recommendations, even though he may not accept the advice. Do educate him. The Know-It-All enjoys being in the know, obviously, and giving him correct information might empower him to make better choices for his pet. Do be agreeable (if you can). If the Know-It-All insists his pet has ear mites, say something like, "He very well may have ear mites. And if he does, you did the right thing by bringing him in for treatment." Do chart all doctor recommendations. If The Know-It-All declines these recommendations, chart that too. Do make an exam room available for The Know-It-All as soon as he arrives, in order to minimize his contact with other clients and their pets. The Know-It-All may not know as much as he thinks about veterinary care and could offer incorrect information to other clients. Debbie Allaben Gair, CVPM, is a Firstline Editorial Advisory Board member and a management recruiter and coach with Bridging the Gap in Sparta, Mich. Christine Hall Johnson is practice manager of PetsFirst! Wellness Center in Brigham City, Utah. Post your comments and questions on the community message board at dvm360.com/comment.

Clients are not your friends

Friends and family bring a lot of great things into our personal lives, but they also bring stress. For example, my wife is days away from giving birth to our second child. While she has been amazing through the past nine months, the reality is that spending time with a pregnant woman can be a bit like spending time in a field full of landmines. I recently explained this to the manager at the grocery store when I found the entire ice cream section off-limits after a freezer malfunction. He was about 18 and had no idea why I was so upset. He'll learn someday.

I care deeply about the anxieties and problems of my family and friends. The exhaustion and discomfort my wife experiences daily are things that I internalize and carry around with me. Her happiness and her perception of me affect how I see myself as a person and a spouse. When my friends struggle or ask for advice, I take their concerns on my shoulders and roll them around in my mind as I cook dinner, brush my teeth and read princess stories to my daughter. I take these stresses on because I love these people and because they are important in my life. But when a client causes that stress, that's another story.

A client with two faces

Recently, a client started visiting the clinic on a regular basis. She had brought home a new puppy, and I helped her work through her puppy wellness visits, a few behavioral bumps, a spay and some inappropriate urination problems. She has a great dog, treats the clinic's staff well and follows recommendations religiously. She lives near one of our technicians and always talks to her and high-fives her children when they're out in the neighborhood. I like this lady and I'm happy when she walks in the door.

This client was in the clinic recently, and we were addressing her pup's new affinity for urinating on expensive furniture. We laughed, she let her dog lick her mouth to the point that I got a little queasy and we generally had a good time. She elected to start a common antibiotic while awaiting diagnostic results.

Things changed a bit the next day. My receptionist came to me five minutes before closing. She said the client was on the phone, she wasn't happy and she wanted to come in. I asked the receptionist to tell her that I'd wait for her if she came right away. I was wrapping up the last of my paperwork when I heard her walk in and say: "Yeah, the pills Roark gave me yesterday f***ed up my dog!"

"Surely she's joking," I thought. "She can't be swearing at the front desk about anything an antibiotic did to her dog." I expected her to high-five me for waiting for her rather than blow up in the waiting room.

The exam went fine, other than the fact that she refused to look at me and swore that nothing could've caused her dog's behavioral change besides the single dose of antibiotic from the previous night. I did everything I could to pacify and educate this concerned and angry client before she walked out of the clinic without paying for the exam or any of the supportive care we provided. Three days later she called to mention that the dog was doing much better and that she remembered the patient might have fallen out of a van and landed on her neck shortly after receiving the antibiotic.

The aftermath

As I stood in the waiting room and watched the client drive away, I asked myself how deeply this person's anger would affect me. It's possible for me to let something like this wreck an entire weekend—especially when I'm so adept at devising creative ways to blame myself for medical phenomena over which I have no control. As I pondered my role in this patient's condition, two hard-learned lessons floated back to me:

1. You're never as good—or bad—as clients think you are. I once talked to a college professor about the reviews he got from students. He said that the key to taking feedback is to remember that no matter what you do, 10 percent of people will think you walk on water and 10 percent will think you're the worst person they've ever met. Neither group is right, so remove both from consideration and use the rest of the feedback to improve what you're doing. He was right. Don't let the clients who love you or those who despise you control your self-image or self-confidence.

2. Clients are clients, not friends or family. As a general rule, I like my clients. There are some clients I adore. I go the extra mile for them, check on them from time to time and visit their homes if they want me to perform euthanasia in that setting. But they're not my friends or my family.

Lesson learned

The difference between clients and friends is that friends don't pay me for my time during the majority of our interactions. I say the majority because I do have friends who bring their pets to me. Secondly, clients have a nasty habit of substituting entitlement for friendship and becoming very upset when they feel let down. And finally, while I accept the stress of family and friends, I choose not to take the emotions and frustrations of clients home with me.

Obviously, I hold onto the positive energies that clients bring for as long as I can, and some experiences I simply can't hang up with my white coat before clocking out. For the most part, I give my clients my best when I'm at work, I make sure they know who to go to if problems arise before I return to the clinic, and then I go home, making sure to pick up ice cream on the way.

Dr. Roark is an associate veterinarian in Leesburg, Va.

Scientific Stuff…Coming Soon

    It’s only few days on launching a new web site called Scientific Stuff, a new revolution in popular scientific networking world that will include most known sciences and public issues that publics care for and try to know as much as they can of important and daily information on everything goes around us in such an easy way without any complications. Scientific Stuff takes a logo of “ Scientific Vision For Different Life “, that enhance its role in spreading the scientific vision and establish a successful scientific network. Scientific Stuff is managed by a stuff of ambitious undergraduate students in collaboration with some establishments in Egypt. We hope all people get most benefit of this site.