Headlines on trial: The diluted truth

We live in a society that embraces things for being “alternative.” And that’s fantastic. If that wasn’t the case, American Idol would be the only show on TV, and Radiohead’s new album (or the seven before it) would hardly be the talk of the town. In other words, the world would be a far less interesting place.

But the alternative route becomes a problem when an idea gains merit simply for being unorthodox — when going against the status quo is sufficient to garner credibility. The field of homeopathy has been riding this wave for more than 200 years.

In the popular understanding, homeopathy is readily lumped in with all things alternative and “natural.” Yet, rather than being a hazy branch of complementary medicine, it is actually a field with a unique history and a wealth of literature to boot. Its skeptics are fierce, and its proponents still fiercer. Welcome to Homeopathy 101.

When the 18th century drew to a close, the German physician Samuel Hahnemann came up with a rather outlandish notion: that the best way to treat a disease was to use a substance that induces its symptoms in a healthy individual. Considering that his peers were busy bloodletting and prescribing leech therapy, this idea may not have seemed too far from the norm.

The theory was inspired by Hahnemann’s reaction to cinchona bark, a common treatment for malaria at the time. Since ingesting cinchona made him feel “languid and drowsy,” symptoms which he felt were similar to those of malaria, Hahnemann concluded that this property must be essential to its medicinal effects. Thus, the field of homeopathy was born.

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But there was a problem here. People were probably not too fond of taking medicines which had been specifically chosen to induce the symptoms they were already suffering from. To get around this inconvenient hurdle, Hahnemann added a further innovation to his recipe. He decided that the more you dilute a substance, the more you can “potentize” its healing abilities.

Any old dilution wouldn’t do the trick. In order to be effective, this procedure had to be carried out by administering ten hard strikes against an elastic object (a process referred to as “succussion”). Only then would you be able to activate the “spirit-like essence” of the substance being diluted.

What’s more, it’s remarkable how much diluting it takes to release the genie in the homeopathic bottle. We’re not talking about a splash of water in our whisky here. Homeopaths measure dilution on a centesimal (or C) scale, which involves diluting a substance by one part in 100 at every step. Given that your typical homeopathic treatment comes at a dilution of 30C, that equates to a dilution factor of 10 to the power of 60.

To put this in perspective, skeptics have noted that a dilution of 12C is the equivalent of adding a pinch of salt to the Atlantic Ocean. Quite some splash of water.

It’s convenient, then, that central to the current homeopathic philosophy is the idea that the elaborate process of succussion leaves an imprint of the diluted substance on water, or a “water memory.” The fact that this notion is widely refuted by physicists, chemists, and common sense alike is apparently of little concern to the homeopath.

Today, the concepts of “like curing like,” potentization, and extreme dilution persist largely unchanged within the homeopathy industry. In fact, they form the basis of a huge number of “remedies” in the homeopathic arsenal.

Whether or not you find these ideas credible is a matter of individual judgment. Personally, I like to have at least 12 molecules of active ingredient in any medicine I take. But that’s me. The seeming impossibility of the method should not be the sole reason for dismissing homeopathy. After all, there are more things in heaven and earth than are dreamt of in our philosophy.

What really matters is the clinical evidence for homeopathy. Specifically, how does it measure up under the inspection of a controlled clinical trial?

When it comes to this pivotal question, there is a huge amount of evidence out there — enough to give ammunition to both sides of the debate. Even for the hardened observer, the prospect of trying to unravel the key message from this tangled web of data can be rather daunting.

To help resolve this issue, it’s time to introduce another key concept of clinical science: the meta-analysis. Don’t be put off by the scary terminology. A meta-analysis essentially involves combining all the data from multiple, small trials into a single coherent analysis, then seeing which way the weight of evidence leans. It’s a pretty logical concept, and it might not be too unfamiliar. Rotten Tomatoes has been doing exactly the same thing for film reviews for years.

Crucially, a meta-analysis can reveal a significant clinical effect for a particular intervention when each individual trial had failed to recognize it. Alternatively, this method can dispel the apparent virtues of a treatment when some of the smaller trials might suggest otherwise. This makes it the perfect tool for examining the clinical evidence on homeopathy.

So what do the meta-analyses (and there have been several) have to say on the matter?

Perhaps the most comprehensive of these studies, examining 110 independent trials on homeopathy, was published by Professor Matthias Egger in The Lancet in 2005. In each trial, the therapeutic effect of a homeopathic treatment was measured (basically, did the intervention do anything?). But perhaps more importantly, the quality of each study was scrutinized. For instance, how big was it? Was it randomized? And was it blinded? All important stuff, which can drastically influence the outcome of a clinical investigation.

Here’s what it boiled down to (cue drum roll): while small, low quality trials often reveal a therapeutic effect for homeopathy, the better the study, the smaller this effect tends to be. And if you look exclusively at the largest, most scrupulous trials, homeopathy performs no better than placebo.

When it comes to issues of public health, we deserve the undiluted truth. If a remedy does not contain a single molecule of active ingredient, and cannot weather the scrutiny of a controlled clinical trial, it probably shouldn’t form the basis of a multi-billion dollar global industry.

Conventional medicine is far from flawless. It is built, however, on a system of constant re-evaluation, in which obsolete and ineffective practices are cast aside. Somehow, homeopathy has escaped the scrapheap.

Read Headlines on trial: The power of evidence

What happened to StudentsFirst?

In The Varsity’s February 28 issue it was revealed that StudentsFirst had decided to boycott the UTSU elections after alleged last-minute disqualifications. StudentsFirst presidential candidate Matthew Gray alleged that VP external candidate Rohail Tanoli and board of directors candidates Cloe Bilobe and Suzannah Moore were notified shortly before the all-candidates meeting that they did not receive sufficient nomination signatures to enter the race.

Before announcing the slate’s boycott Gray inquired as to whether the candidates could enter the race if an appeal found that they had the sufficient number of signatures. Both the CRO and the elections and referenda committee refused to provide a definitive answer.

On 3 March 2011 the CRO issued an interim report on the “ineligible nominees for the 2011 UTSU Spring Elections.”

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The report found that Rohail Tanoli — StudentsFirst nominee for Vice-President, External — received 217 nomination signatures, of which only 187 were eligible. Executive candidates are required to submit 200 eligible signatures to enter the elections race. Upon a recount on 2 March 2011, Tanoli’s inelligibility was confirmed.

StudentsFirst candidate for New College Director, Cloe Bilodeau, received a total of 21 nomination signatures. Board of direcors candidates are required to submit 25 signatures to enter the elections race. Victoria College Director Suzannah Moore submitted a total of 26 nomination signatures, of which only 21 were verified to be eligible.

Free association is a fundamental right

Elections plagued by a traditionally high incumbency rate and traditionally low voter turnout seem to be the model of democracy at U of T. Add to that a recent boycott of the upcoming UTSU elections by the only major opposition slate and it seems that student politics at the U of T are doomed to dysfunction. Students feel either apathetic and uninvolved or completely disenfranchised, and many believe the current system is not able to adequately address their concerns. Presented with this reality we are forced to ask the question: why are students required to be part of the union at all?

In 1948, Canada voted for the United Nation’s Universal Declaration of Human Rights. In 1982, we adopted our own Charter of Rights and Freedoms. In both these documents, freedom of association is listed as a protected right. The UN Declaration stated explicitly that no human being can be “compelled to belong to an association.” This right is absent at U of T. In direct contrast to both these documents, students are compelled not only to be part of the student union, but forced to pay dues whether or not they agree with how their money is being spent.

The current channels by which students can express their concern are criticized as being insufficient and biased towards the status quo. The turnout rate for past elections has rarely exceeded 10 per cent, with the near complete re-election of the incumbent members. When 60 per cent of Canadians turn out to vote, federal elections are lambasted as being unrepresentative. How representative, then, can UTSU be?

It is not surprising that students feel a sense of disenfranchisement, as the only channel available to them to affect policy change seems to be broken. The lack of such democratic accountability has led to the boycott of upcoming UTSU elections by the opposition slate, StudentsFirst.

These problems, however, are not restricted to U of T nor, indeed, to Canada. New Zealand has confronted these concerns by pushing for voluntary student union membership. Sir Roger Douglas, former Minister of Finance and currently an MP for the ACT Party, is championing a bill that would give students the choice to join a union or not. When asked for comment, Douglas stated, “At a fundamental level relationships between individuals and society should be based on consent. […] They should be based on voluntary cooperation.” It was this principal he sought to extend to student union membership. Involvement in UTSU is, of course, anything but voluntary.

If students had the choice to opt out of UTSU, the union would no longer be answerable only to rival slates at election time, but to every student. The Union would be held constantly accountable and would need to provide tangible improvements to student life. Students who felt they were best served by the union would keep their membership, while those who felt their concerns remained unaddressed could, if the democratic channels consistently failed them, opt out. To prevent freeloaders from benefiting from UTSU funds while not paying dues, simple caveats could be introduced. For example, a club wishing to receive UTSU funding might be required to have a majority of dues-paying members to be eligible.

The argument against this practice is, of course, that the union would then be sapped of funds and rendered unable to supply needed services. When confronted by this question, Sir Roger Douglas explained, “Any organization that can deliver services their customers want [���] will have no trouble attracting [membership].” In the case of student unions, if they “really do provide [needed] services […] then they should have nothing to worry about.” Experiences of voluntary student unions — which are the norm in Australia — have found this to be the case. While the budgets of some were depleted, many others actually saw an increase in funds as they focused their efforts on improving student life instead of championing political causes. It should also be noted that voluntary student unions have found sources of income outside of student levies (some being able to eliminate dues altogether) by receiving, for example, funding from local businesses who benefit from student patronage.

Ultimately, however, this issue goes beyond material arguments. The fact is that freedom of association is a Charter and human right. Even if voter turnout were 90 per cent and there was regular turnover in student representation, those individuals who felt UTSU did not reflect their interests should be guaranteed the ability to opt out. It is every student’s right as a human being to do so. As Sir Roger Douglas said on the floor of the New Zealand Parliament, “Associations […] are not truly representative of their members’ convictions if they are forced to join. They are, in fact, meaningless — the mere playthings of those who control them.”

Not enough space

A Governing Council meeting last October had to be briefly adjourned after several student protesters staged a protest inside Council chambers.

The upheaval was caused by the Policy on the Temporary Use of Space — administrative lingo for space booking — a two-page document outlining a new university policy on campus space. The document aimed to put current space bookings practice in print by updating the last policy, which was implemented in 1988 and only applied to the St. George campus.

The policy met controversy over a paragraph stating that “the university may, as a condition of booking, require that authorized security be made available during the use of the space […] at the cost of the user and to be arranged by the university.” In addition, it says that “the university at its discretion may assess additional security requirements and require that campus police be present at any event.”

Clubs lobbied student representatives to vote against the policy while students protested outside Simcoe Hall. The policy passed, accompanied with a set of procedures outlining how it should be implemented, to be determined by a nominated committee.

Student groups alleged that the security cost provision smacked of censorship, allowing the university to financially penalize groups who hold controversial events.

In 2006 and 2007, the Ontario Public Interest Research Group held two on-campus talks related to the Israeli-Palestinian conflict. In both cases, campus police determined the event to be a security risk, sent police officers, and later billed the group hundreds of dollars for security.

“I cannot recall the last time a campus group was, without requesting campus police to be present, forced to pay for the costs of campus police to be at an event,” said Jim Delaney, director of the office of the Vice-Provost Students. He added that unlocking a building after hours is sometimes annotated as a security cost.

Despite student skepticism, the policy stresses that fees should remain a rare occurrence.

“We normally do not charge recognized campus groups and student societies at all, except for reasonable cost recovery for additional services beyond making the space available (such as post-event cleaning),” it reads.

Provost Cheryl Misak told The Varsity that, although student groups could be charged if any event’s security costs were unusually high, the situation would be exceptionally rare.

“We’re working very, very hard to not charge student groups with security costs,” she said.

Established by the provost’s office in January, the Advisory Committee on the Temporary Use of Space is a group of student and administration representatives from all three campuses. They review and make recommendations on the procedures outlined for the newly approved policy, and examine how student activity space should and can be allocated.

The committee is being facilitated by Delaney, and its second meeting is next Monday. Here’s a breakdown of what it will be dealing with.

St. George campus

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The Office of Space Management oversees most room bookings on campus. Almost all OSM spaces are classrooms and seminar rooms, which are booked through its online booking service.

Many spaces on campus don’t fall under the authority of the OSM. While some rooms in the constituent colleges (Innis, New, University, and Woodsworth) are bookable through OSM, others are entirely managed by the colleges that own them. The federated colleges (St. Michael’s, Trinity, and Victoria) as well as the Faculty of Music, and Wycliffe and Knox colleges have wholly separate booking procedures. Colleges often give preferential treatment to their own clubs; some spaces are effectively barred from out-of-college clubs.

The OSM doesn’t charge recognized campus groups for space usage.

“One of the main issues we’re hearing from student groups is that they cannot always get bookings for space in the exact spaces they seek without incurring additional costs because the building needs to be opened up or because there are some additional costs that are connected to using certain types of space (e.g. caretaking costs),” Delaney said. “The question for us to explore is how we can make more desirable space available at a lower cost.”

“The office isn’t funded as well as it should be,” said UTSU VP Campus Life Corey Scott, noting that all campus group booking requests go through one OSM staff member. “I just don’t think U of T sees it as a priority, really.”

Groups can make reservations at a maximum of four weeks beforehand — a limit that doesn’t exist for external groups.

“In terms of what club executives are saying when they come to me — trying to find shortcuts or ways to get through a bunch of these policies — is that it’s incredibly frustrating,” said Scott.

The issue isn’t just indoors. Last October, the World Cup of Clubs soccer tournament, a day-long event organized by multiple cultural groups, was denied its request to use the King’s College Circle field for the full day. OSM cited office policy and students’ need to cross the field. Event organizers said the number of participants had to be limited and criticized OSM for what it deemed unwritten rules.

Hart House offers most of its rooms to students for free, with certain exceptions for larger venues.

Satellite campuses

Both UTM and UTSC have student centres, opened in 1999 and 2004 respectively, that serve as hubs of campus life. Both buildings are partially autonomous, with the local student union designating space usage. They contain offices of the campus’ student union, radio station, newspaper, pub, and sexual health centre, and also have multipurpose rooms for club meetings and events.

Although the UTSC student centre has club lockers, it has no office space to offer.

“We’re in a really tight squeeze when it comes to campus space,” said SCSU VP Campus Life Matthew Zajch, who compares the rapidly growing campus to “a kid who’s outgrown his clothes; it’s uncomfortable and you know there’s easy ways to fix it.”

With an athletic centre and a slew of campus buildings expected for the 2015 Pan Am Games, Zajch hopes university administration will offer some newly vacant space to students.

UTSC has a dance group culture, with more than a handful competing in monthly events. But with no designated dance studio and overused athletic facilities, many rehearse after-hours in open spaces across campus.

Booking space outside the student centres also seems easier at the satellite campuses. At UTSC the Campus Life Fund assists recognized groups with university-administered event costs, such as rental and clean-up fees. At UTM, clubs organize audiovisual needs for a fee with the campus’ technology department, but other fees are highly uncommon.

Student commons

St. George campus doesn’t have a student centre. Its closest match, the Sussex Clubhouse, houses over 50 campus groups in only three floors. It has limited rooms for clubs to meet in, although they are free to book, even in the evening. The building itself has finicky plumbing, cracking paint, and multiple asbestos warnings.

Both York and Ryerson universities have student centres, with club offices and multipurpose spaces.

Plans for a similar building for St. George campus have been kicking around for nearly six decades, repeatedly falling victim to competing visions and funding shortfalls.

A 2007 UTSU referendum approved a $20 million levy to pay two-thirds of the cost of a new Student Commons. UTSU collects a five-dollar levy each semester, which will rise to $14.25 when the centre opens. U of T administration will pay the remaining third.

Last November, the UTSU board of directors voted to resituate the project to 230 College St., current site of the Faculty of Architecture Landscape and Design building.

“I know the student commons will be a huge asset for clubs that need space on campus but don’t want to go through the hassle of OSM,” said Scott.

The project, still in the planning stage, aims to offer boardrooms, kitchens, office space, multipurpose rooms, and lecture halls, ostensibly by mid-2012.

Who signs it anyway?

One of the biggest points of contention among campus clubs is signing authority. At the moment, each club can use one signing officer. Requiring all events go through one single executive, combined with only being able to book events four weeks ahead, means clubs have a difficult time booking space in a speedy manner. Some groups have cancelled events after finding no compatible time.

A 2006 provost-authored report recommended that “campus groups be permitted to identify up to two contact people who are authorized to reserve space” and references a similar 1999 recommendation.

“At the time, there were some technical issues associated with the recommended change that made it difficult to implement,” said Delaney, adding that he expects a change “in the near future.”

When told that Ulife, U of T’s student life repository, allows upwards of four signing officers on its clubs recognition application, Delaney said it was a database issue.

“If I recall correctly, the issue was specific to the way the campus groups database was designed at the time and how it delivered information,” he said.

A year in review

The Varsity Blues men’s hockey team finished their season on February 19 in game 3 of the OUA East quarter-finals against the Carleton Ravens.

The Ravens won the best-of-three series 2–1 to advance to the OUA East semi-final round.

According to captain, Andrew Kizito, the team “came into the playoffs as the underdog with few people around the league expecting [them] to win.”

Having lost key veterans, Joe Rand, Eddie Snetsinger, and Brendan Sherrard last season, the Blues faced the difficult task of rebuilding a winning squad.

“When a team loses star caliber veterans, it’s always going to have an impact on the next season. Players of that quality are always difficult to replace,” said Kizito.

Faced with a tough task, the team got off to a slow start and didn’t earn their first regular season win until the end of October.

Kizito credited the slump to the team’s inability to keep composure during clutch moments of a game.

“This season we struggled to play a complete 60 minute effort night in and night out,” he said.
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The remainder of the season fared better for the squad, who figured out their team identity going into the second half following Christmas break.

In an exhibition game played over the holidays, the team beat the St. Mary’s University Huskies, the defending national champions, in a shootout.

“This victory provided a young team with a great deal of confidence as it proved that they could play with and beat anyone,” said Kizito.

Kizito thinks that it was a successful rebuilding as the team was able to make the playoffs.

“The good thing is that we showed improvement over time. No matter how bad or good a team is at the start of a season, the key to judging the success of a season rests upon whether or not the team improves or not.

“We made progress in the right direction, which I believe will carry into the next season,” he said.

Kizito is looking forward to getting back on the ice as he feels that the future is bright.

“This upcoming season I expect to see a maturing nucleus that has learned from this [rebuilding] experience. I expect to see a team that plays every game like it’s their last.”

Free wired

Last week’s alleged penetration of sensitive federal government networks by China-based hackers demonstrates the need for greater communications security in Canada. While the hackers did not steal any crucial secrets, they did gain access to the internal networks of three government departments responsible for the federal budget. It is unclear whether the hackers’ activities were state-sponsored, but if they were, this breach could amount to a 21st-century version of economic espionage. If the hackers had stolen budget secrets, they could have passed them on to investors who would then be able to make bets on the effect that the budget would have on Canadian stocks.

This breach highlights the paramount importance of keeping government communications safe. For the past decade, Canadian national security policy has focused nearly exclusively on counterterrorism. While the capacity of state-sponsored and freelance hackers to infiltrate government networks has significantly increased, it is unclear whether Canada’s capacity to defend itself from these kinds of attacks has increased at anywhere near the same rate. A decade spent focusing on terrorism has come largely at the expense of understanding and responding to other kinds of threats. This breach proves that it is now time to correct this security gap.

According to several reports, human error seems to have been responsible for this breach. Senior officials within the three departments were contacted with offers tailored to their status as “executives” within the government. Using the information provided by the officials who responded to these offers, the hackers accessed their computers remotely and sent requests to the department’s support staff for network passwords posing as the executives. With these passwords, they attempted to gain access to secret and top secret budget documents. However, communications security staff detected these infiltrations before the hackers could steal any sensitive information and prevented them from doing so.
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Though the successful defence mounted by Canadian security officials should be lauded, it is important to ensure that public servants take steps to prevent these kinds of breaches. Government security staff should require greater use of encryption, randomization, and other techniques that would make it harder for hackers to use any information they obtained. Moreover, they should expand the use of secure communications technology and alter existing technology, especially BlackBerries, to prevent the use of functions, such as instant messaging, which cannot be effectively secured. Such a program would be costly, but is crucial for keeping key government departments connected, but secure.

The Communications Security Establishment, whose staff successfully repelled the attack by Chinese hackers, would coordinate an expanded communications security program. CSEC is responsible for securing government communications, and also gathering intelligence on external threats to Canada’s national security, which it does by intercepting communications in cooperation with sister agencies in Australia, New Zealand, the United Kingdom and the United States. Since the September 11 attacks, its staff has expanded to meet growing intelligence gathering responsibilities. CSEC should be further expanded to meet the federal government’s need for greater communications security coordination.

CSEC is unique among Canadian intelligence and security agencies as it is directly supported by the Canadian military and under the authority of the Minister of National Defence, rather than the Minister of Public Safety. There is a special unit within the Canadian Forces, the Canadian Forces Information Operations Group, which is responsible for providing technical assistance to CSEC. It too should be expanded to provide additional support to CSEC especially in the area of communications security. Eventually, the Canadian government could also consider following the American model by creating a small, flexible “cyber command” to unify the military’s cybersecurity activities.

Within the context of current discussions between the American and Canadian governments on the possibility of more comprehensive security cooperation, our government should also consider whether Canada should cooperate more formally with the United States on cybersecurity. Eventually, this could take the form of adding a cybersecurity dimension to an expanded NORAD partnership, which would see the American and Canadian militaries ensure North American security in the air, at sea, and online. This “cyber-NORAD” would help Canada keep itself safe from this kind of cyberattack and build on decades of close intelligence and military cooperation between Canada and the United States.

While the infiltration attempt revealed last week was unsuccessful, foreign hackers will undoubtedly continue to try to penetrate Canada’s secure government networks. They will surely develop more sophisticated ploys and techniques aimed at stealing key government information. Canada must prepare to meet this threat head on by strengthening security, by improving vigilance among public servants, beefing up its civilian and military communications security staff, and better coordinating online defence activities with the United States. Perhaps these changes will take a successful attack on Canada, but hopefully the government will take note now and take the crucial steps to prevent future breaches.

A good sport: Summer around the corner

Toronto’s Major League Baseball team is coming off a good 2010, but there are several looming questions that will affect their success in 2011 and beyond.

Spring training has actually been going on for over two weeks and the first regular season game is less than a month away.

The Toronto Blue Jays are starting a new era, a post-Cito Gaston era. Boston Red Sox pitching coach John Farrell is leading the Jays now, and he promises to bring a new approach to a team whose fans were often both baffled and frustrated by Gaston’s fidelity to widely rejected old-school assumptions about how to run a baseball team.

The club finds itself coming off a remarkable 2010 season. It exceeded all expectations to post 85 wins (some thought they would win as few as 65) and important pieces of their future took huge leaps forward. It’s possible that the Jays could take a step back in 2011 in terms of wins and losses, yet still make progress towards the medium-term goal of a World Series championship.

Here are three big questions that will shape not only the Jays’ 2011, but the next five years or so.

1) Can the pitching keep it up? The Jays’ young pitchers made huge strides forward last year. Brandon Morrow, Ricky Romero, and Brett Cecil all emerged as potentially elite starters. The Jays also have a plethora of less-talented but still serviceable starters, including Jesse Litsch and Marc Rzepczynski. Most importantly, two studs in the minors — Kyle Drabek and Zach Stewart — could both see Major League time this year (in fact, Drabek is highly likely to be one of the team’s starters to begin the year). But the Jays’ pitching has been almost too good to be true. Young pitchers often suffer injuries and on-field setbacks. Can the Jays’ core keep it together? All signs point to yes, but you can never have too much pitching.
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2) Can Adam Lind transition to first base? Lind has always been an awkward-looking defensive player and extremely young to be a full-time Designated Hitter (a role usually reserved for older, beat-up veterans). For lack of an impact first baseman in the system, the Jays have opted to try him out full-time at first base and see what he can do. He has shown the potential to be an elite hitter (despite a dreadful 2010) but his viability as a useful asset to the Jays mostly hinges on whether or not he can play passable defence.

3) How will the club fare post-Vernon Wells? The face of the Jays franchise was traded to Anaheim to shed a tortuous contract. Finding a team to trade for Wells was nothing short of a miracle and a great move for the organization. But the hot and cold All-Star has been a fixture of the Jays clubhouse for nearly a decade, and a new generation of leaders will need to replace him. If the very young Travis Snider can have the breakout offensive year most believe he is capable of, that will go a long way to replace the solid offensive season Wells had last year that he won’t be contributing to the Jays anymore.

New HIV vaccine?

Engineers from MIT have designed a new type of vaccine that could potentially be used to prevent HIV and malaria safely and much more effectively. These new particles are described in the February 20 issue of Nature Materials.

The particles are formed out of concentric spheres made of fat. They carry synthetic versions of virus protein particles in their core. These nano-sized lipid-based vaccines can elicit the same strong immune response as a live virus vaccine, but are much safer due to their synthetic virus particles.

Vaccines work by priming your immune system. By exposing the immune system to an infectious agent, it can more easily recognize and destroy the same pathogen during a later encounter. Vaccines are designed to incite the production of either T cells (which destroy infected cells) or B cells (which secrete antibodies to target pathogens).

However, a vaccine for HIV — much like those for polio and smallpox — requires the activation of a subset of T cells called the killer T cells, using a weakened or disabled virus. Creating an HIV vaccine using a live virus is difficult because it is hard to render it harmless.

Some vaccines, like the diphtheria vaccine, can use recombinant or synthetic proteins, or molecules normally made by the virus. However, this route is inadequate for HIV or Hepatitis B vaccines, because the synthetic particles don’t elicit the same strong T cell response.
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Recently, scientists have tried working with the idea of encasing these synthetic vaccines in liposomes, or fatty droplets, which resemble normal viruses and can help stimulate killer T cells. Normally, however, these fatty droplets are unstable in bodily fluids.

Postdoctoral fellow James Moon, associate professor Darrell Irvine, and their colleagues at the Massachusetts Institute of Technology have developed a more stable way to assemble liposome nanoparticles. The virus antigen particles are packaged in multiple concentric liposomal spheres. The headgroups of adjacent lipid bilayers are then crosslinked, a technique to make them more stable and less likely to break down upon injection. The lipid bilayer structure allows these nanoparticles to be absorbed by your cells. Once inside, the harmless synthetic virus particles are released in the presence of enzymes that break down fat, called endolysosomal lipases. This provokes the killer T-cell response.

Moon and his colleagues used these nanoparticles to test the T-cell response in mice, to a protein called ovalbumin. They found that, after three immunizations using low doses of the vaccine, up to 30 per cent of all killer T cells in the mice were specific to the vaccine protein.

These results are comparable to vaccines that use live viruses, but they are much safer to prepare and use. The vaccines also elicited a strong antibody response. Researchers have yet to discover whether these vaccines can elicit the same strong response in humans.

So far, these newly constructed nano-sized lipid based vaccines are making for a potential safe delivery system for vaccines against hard-to-handle viruses like HIV or hepatitis B. Irvine and his colleagues have since moved on to try and develop these vaccines to immunize people against malaria, HIV, and cancer.