Friday, July 29, 2011
Le Cabaret Frappe
So, I got out of the lab around 6:30PM today and decided to head into town for some dinner. I went to the usual area to find some food and noticed some music and purple lights in the distance. To my surprise they were holding a concert in one of the parks near Victor Hugo (this is the central park of downtown). It was called Le Cabaret Frappe. I saw the flyers for it earlier in the week, but didn't realize it was a public concert, apparently it was playing from July 23rd -29th. Usually there are night concerts starting at 7PM and playing about 3 bands a night, one at 7, the others at 9 and 11. I went for the 7PM showing and guess who I saw, Michel! He was using his bike as a stool and was perched up near a tree. The group that was playing, HK & Les Saltimbanks, had a reggae, hip hop, rap feel. I didn't really understand what they were singing about, Michel said it was political in nature, but either way it was very nice to hear. One thing I do like about the French music is the incorporation of the accordion. If you have the chance, you should check out some of the bands on the cabaret frappe website.
Wednesday, July 27, 2011
Nice Evening Meal
Phew. Just finished dinner. It was a home cooked meal for once. Well, as home cooked as one can get when living in a guest house with limited cookware and spices, but nonetheless enjoyable and, at least for me, soothing. This week and next week will be stressful. My time here in Grenoble working with the Vivaudou Group is coming to a close and, as with all endeavors to achieve results, results are slow to appear, which is in contradiction with what I hoped to achieve here. Then again, I guess I couldn't really say how much work could reasonably be accomplished in seven weeks.
Cooking is nice because it provides time to reflect. In between chopping, sauteing, seasoning, and allowing each of the flavors to meld, the day's pace slows down and you can spend more time processing and assessing things you couldn't throughout the day. This evening was one of those cases. Lucky for me that I had a special treat. Anne brought me a bag filled with fruits (fruits, French word) and vegetables (legumes, French word) from her garden. =) I've a picture of the gifts below. The tomatoes were awesome. They had a sweet tinge to them and lacked the acid notes found in grocery market tomatoes. These, were real tomatoes ripened on the vine. Along with the tomatoes (tomates), there were zucchini (courgent) and squash. With the tomatoes I made a tomato salad with pieces of herb cheese. The zucchini was sauted in butter, along with some beets I had in the fridge. In addition, I made my own rendition of a croque monsieur by pan frying buttered bread with pieces of Gruyere cheese and ham in between each piece of bread and finally finished the meal with an apple and some bread and cheese. Yum.
Looking at it, I've at least come to better understand how to perform the basics of patch clamping and have been introduced to other techniques, like two electrode voltage clamp (TEVC) and droplet-interface bilayers (DIBs). Each time, I learn a bit more about the oocyte system I'm using, whether it be methods to stabilize membranes which show no promise and others which have shown hints of promise but require further investigation. Little by little, we'll tease out an answer, but in a short time, probably not. That's science. It's funny though, when you observe a different outcome you want to investigate it more and more and in doing so you've come to better understand your system of study. Since many of these experiments are new to both our groups, we are doing just that, and at the same time trying to provide a biological or chemical explanation for the outcome we see. That's why it's sometimes good to have a nice evening meal as it provides time to reflect on the days events, consolidate and organize the various attempts made and their respective results, provide an explanation or possible explanations for your results, and construct future experiments to support or disprove your hypotheses. Each takes time and why not spend some time thinking over some nice food.
Cooking is nice because it provides time to reflect. In between chopping, sauteing, seasoning, and allowing each of the flavors to meld, the day's pace slows down and you can spend more time processing and assessing things you couldn't throughout the day. This evening was one of those cases. Lucky for me that I had a special treat. Anne brought me a bag filled with fruits (fruits, French word) and vegetables (legumes, French word) from her garden. =) I've a picture of the gifts below. The tomatoes were awesome. They had a sweet tinge to them and lacked the acid notes found in grocery market tomatoes. These, were real tomatoes ripened on the vine. Along with the tomatoes (tomates), there were zucchini (courgent) and squash. With the tomatoes I made a tomato salad with pieces of herb cheese. The zucchini was sauted in butter, along with some beets I had in the fridge. In addition, I made my own rendition of a croque monsieur by pan frying buttered bread with pieces of Gruyere cheese and ham in between each piece of bread and finally finished the meal with an apple and some bread and cheese. Yum.
Looking at it, I've at least come to better understand how to perform the basics of patch clamping and have been introduced to other techniques, like two electrode voltage clamp (TEVC) and droplet-interface bilayers (DIBs). Each time, I learn a bit more about the oocyte system I'm using, whether it be methods to stabilize membranes which show no promise and others which have shown hints of promise but require further investigation. Little by little, we'll tease out an answer, but in a short time, probably not. That's science. It's funny though, when you observe a different outcome you want to investigate it more and more and in doing so you've come to better understand your system of study. Since many of these experiments are new to both our groups, we are doing just that, and at the same time trying to provide a biological or chemical explanation for the outcome we see. That's why it's sometimes good to have a nice evening meal as it provides time to reflect on the days events, consolidate and organize the various attempts made and their respective results, provide an explanation or possible explanations for your results, and construct future experiments to support or disprove your hypotheses. Each takes time and why not spend some time thinking over some nice food.
Le diner
Saturday, July 23, 2011
Le Tour de France
What an exciting day. The Tour de France held the penultimate stage here in Grenoble. The course was 42.5 km, starting and ending on the northeastern side of town with a climb up through the eastern mountains. The riders have to mountains to climb, first is the Brie-et-Angonnes which sits at 475 m above sea level, followed by Saint-Martin D'uriage which is at 593 m. For reference, Grenoble sits about 213 m from sea level and . Here's a map of the course.
I rode the bus into town and then walked over to the start of the course by about 10AM. It was quite the spectacle. Near the Velodome, each team had set up their trailers and were preparing bikes for the day and eager fans were sitting outside the gates, peering through visible spots cheering on their favored team. There was even a band, yes a band in the musician-sense, of guys dressed as vikings playing rehearsed songs. It was great to see! Other people had bought or brought flags of their respective countries and were wearing them as capes. I walked down the race course a bit and unexpectedly ran into some friends. We parted from the area around a little after 1pm, I to do some shopping, and they to return home and have some lunch.
As I walked back there were a group of students, probably middle or high school, asking us to sign something for the deaf and mute. This particular girl wouldn't leave me alone, so I decided to donate 2 euros. I accidentally took out 1 euro and she asked for the second. I pulled out a 2 euro coin and hoped to take back the 1 euro coin, but before I could, she closed her hand. In the end I ended up giving her 3 euros (150% more than I decided to). I've never experienced such a thing in the U.S. Though people ask for donations and pledges, they don't grab money from you like that. This isn't the first time I've heard to be careful in France regarding people asking for money or donations. In Paris, it's common to see people selling these "love bracelets," woven wristbands. Without asking you, they would try and tie one of these bands around your wrist and then ask for 5 euros. You need to be very careful about this type of "salesmanship." In contrast though, there was another group in Paris near the Gares Montparnasse that was advocating cancer awareness and they were quite pleasant to deal with. So I'm not sure, but in the end, I need to be more cautious.
From here, I returned to the guesthouse, took a nap and then decided to head back into town to see if there were events going on in celebration of the tour de France. In an anticlimatic way, there was none. I didn't hear bands playing. The nightlife didn't seem any busier. Restaurants seemed the same and streets seemed less crowded. Where had all the people who had been there during the race gone? I returned to the area where the race started and found my answer. The caravans had all left, not a single one was still near the Velodome. For the most part, the park was cleared out, you could barely tell there had been a race during the day. The trampled green grass will probably grow back within a week. It's quite a sad scene to see such a well-televised event come and go like that and leave very little trace outside of a poster ornews column. Sigh.
I rode the bus into town and then walked over to the start of the course by about 10AM. It was quite the spectacle. Near the Velodome, each team had set up their trailers and were preparing bikes for the day and eager fans were sitting outside the gates, peering through visible spots cheering on their favored team. There was even a band, yes a band in the musician-sense, of guys dressed as vikings playing rehearsed songs. It was great to see! Other people had bought or brought flags of their respective countries and were wearing them as capes. I walked down the race course a bit and unexpectedly ran into some friends. We parted from the area around a little after 1pm, I to do some shopping, and they to return home and have some lunch.
As I walked back there were a group of students, probably middle or high school, asking us to sign something for the deaf and mute. This particular girl wouldn't leave me alone, so I decided to donate 2 euros. I accidentally took out 1 euro and she asked for the second. I pulled out a 2 euro coin and hoped to take back the 1 euro coin, but before I could, she closed her hand. In the end I ended up giving her 3 euros (150% more than I decided to). I've never experienced such a thing in the U.S. Though people ask for donations and pledges, they don't grab money from you like that. This isn't the first time I've heard to be careful in France regarding people asking for money or donations. In Paris, it's common to see people selling these "love bracelets," woven wristbands. Without asking you, they would try and tie one of these bands around your wrist and then ask for 5 euros. You need to be very careful about this type of "salesmanship." In contrast though, there was another group in Paris near the Gares Montparnasse that was advocating cancer awareness and they were quite pleasant to deal with. So I'm not sure, but in the end, I need to be more cautious.
From here, I returned to the guesthouse, took a nap and then decided to head back into town to see if there were events going on in celebration of the tour de France. In an anticlimatic way, there was none. I didn't hear bands playing. The nightlife didn't seem any busier. Restaurants seemed the same and streets seemed less crowded. Where had all the people who had been there during the race gone? I returned to the area where the race started and found my answer. The caravans had all left, not a single one was still near the Velodome. For the most part, the park was cleared out, you could barely tell there had been a race during the day. The trampled green grass will probably grow back within a week. It's quite a sad scene to see such a well-televised event come and go like that and leave very little trace outside of a poster ornews column. Sigh.
Wednesday, July 20, 2011
Soup and Science
It's been a while since I discussed some science. As to be expected, experiments always take longer than expected and protocols don't always go as planned. We tried polymerizing a patch membrane excised from an oocyte using patch clamp protocols. Patch clamp is a technique developed in 1976 by Neher and Sakmann in order to study ion channels. For their work, they received the Nobel Prize in Physiology Medicine in 1991.
In the simpliest explanation, patch clamp measures the current flowing between two electrodes placed on different sides of an excised piece of cell membrane expressing ion channels or receptors. To excise membrane, a glass capillary is heated and pulled to make a pipette with an 1-3 micrometer aperture. This pipette is pressed against a piece of cell membrane and a small suction is applied, causing the membrane to press against the pipette walls, generating a highly resistive seal (on the order of gigaohms, hence it is called a "gigaseal") and capable of maintaining membrane integrity even after excising a piece by quickly retracting the pipette. Ion channels or receptors carried within the patch maintain their activity and are kept in their native environments for the most part. Agonists and antagonists may be administered to the patch to observe changes in the conductance state (fancy phrase to say how current changes) of the ion channel or receptor.
Explaining how patch clamp works is easy, actually getting a gigaseal is more difficult, and it seemed almost impossible for me today. Christophe didn't seem to have a problem forming a gigaseal, so I must have been having a bad day. To further complicate matters, gigaseals are only formed with still living oocytes. Old oocytes, and any cell for that matter, or dead oocytes have "leaky" membranes and it is incredibly difficult to form a gigaseal. If I recall correctly, we went through three oocytes this morning before we found one which could form a gigaseal, attempting to form a seal at least three times per oocyte. Sigh.
It probably didn't help that I was feeling a bit under the weather these past few days and the rainy weather didn't help but perpetuate the gloomy feel. To perk myself up, I asked Christophe if there were any places to buy soup and bread. To my surprise, soup is not a common food to find in France due to the underlying connatation that only poor people eat soup. In the winter months, eating soup is more acceptable, but in summer, not so much. This is different from America, where year around we can purchase items like "soup and salad," or "half-sandwich and soup" for lunch everyday throughout the year. I think the best example of the U.S. equivalent is where people shop. When I was growing up, I don't remember people openly admitting they shopped at such places as Goodwill, Salvation Army, or the Thrift Store. I feel nowadays, it has become more acceptable, at least among the younger generations to look for clothing there. Apparently there is a spinoff store called the Buffalo Exchange that utilizes some of the same principles, with one exception, that they buy back used clothing and then resell it for reduced cost. I went there last Halloween to purchase some items for my Waldo costume (it's actually quite nice and you can find a couple articles of clothing that are well worth the visit). Either way, a connatation is a connatation. I wanted soup. So, I rode my bike into town, walked into the supermarket bought some soup, bread, saucission, a mixed berry tart, fruit and a couple snacks and had a nice dinner outside in the sunshine with a cup of tea and a paper from Analytical Chemistry.
In the simpliest explanation, patch clamp measures the current flowing between two electrodes placed on different sides of an excised piece of cell membrane expressing ion channels or receptors. To excise membrane, a glass capillary is heated and pulled to make a pipette with an 1-3 micrometer aperture. This pipette is pressed against a piece of cell membrane and a small suction is applied, causing the membrane to press against the pipette walls, generating a highly resistive seal (on the order of gigaohms, hence it is called a "gigaseal") and capable of maintaining membrane integrity even after excising a piece by quickly retracting the pipette. Ion channels or receptors carried within the patch maintain their activity and are kept in their native environments for the most part. Agonists and antagonists may be administered to the patch to observe changes in the conductance state (fancy phrase to say how current changes) of the ion channel or receptor.
Explaining how patch clamp works is easy, actually getting a gigaseal is more difficult, and it seemed almost impossible for me today. Christophe didn't seem to have a problem forming a gigaseal, so I must have been having a bad day. To further complicate matters, gigaseals are only formed with still living oocytes. Old oocytes, and any cell for that matter, or dead oocytes have "leaky" membranes and it is incredibly difficult to form a gigaseal. If I recall correctly, we went through three oocytes this morning before we found one which could form a gigaseal, attempting to form a seal at least three times per oocyte. Sigh.
It probably didn't help that I was feeling a bit under the weather these past few days and the rainy weather didn't help but perpetuate the gloomy feel. To perk myself up, I asked Christophe if there were any places to buy soup and bread. To my surprise, soup is not a common food to find in France due to the underlying connatation that only poor people eat soup. In the winter months, eating soup is more acceptable, but in summer, not so much. This is different from America, where year around we can purchase items like "soup and salad," or "half-sandwich and soup" for lunch everyday throughout the year. I think the best example of the U.S. equivalent is where people shop. When I was growing up, I don't remember people openly admitting they shopped at such places as Goodwill, Salvation Army, or the Thrift Store. I feel nowadays, it has become more acceptable, at least among the younger generations to look for clothing there. Apparently there is a spinoff store called the Buffalo Exchange that utilizes some of the same principles, with one exception, that they buy back used clothing and then resell it for reduced cost. I went there last Halloween to purchase some items for my Waldo costume (it's actually quite nice and you can find a couple articles of clothing that are well worth the visit). Either way, a connatation is a connatation. I wanted soup. So, I rode my bike into town, walked into the supermarket bought some soup, bread, saucission, a mixed berry tart, fruit and a couple snacks and had a nice dinner outside in the sunshine with a cup of tea and a paper from Analytical Chemistry.
Friday, July 15, 2011
Now the REAL work begins
As I depart Grenoble, I am very happy and grateful for the time that we have spent together. I have wanted to collaborate with the Channels Group at IBS for an extended period and we had begun to discuss some rough opportunities to do so last Spring. As many of you know, the activation barrier to discussing a collaboration and actually performing it is quite high. This is particularly true when working to build international collaborations with different time zones, research areas, etc.
The GREET program opened a very important door and made it possible to spend time with our new collaborators and to discuss and plan extensively how to proceed. As I leave Grenoble, we have a very clear plan with defined action points and items that we will continue to develop. Further, I leave Mark behind to continue collecting preliminary experimental data, learning new techniques and making a new sensor protein that will form the basis for some of our future works. While it is possible that our groups would have still found the time and effort to collaborate, the GREET program enabled that opportunity to be accelerated and strengthened. So for that, I’d like to say a special THANK YOU to ACS, the ACS Office of International Activities and the GREET program staff.
Thursday, July 14, 2011
Bastille Day
Today is Bastille Day (English term), or more commonly called La Fête Nationale, and in France, it marks the anniversary of the storming of the Bastille on July 14, 1789 and the start of the French Revolution. In a sense it is similar to our Independence Day and is filled with celebrations around town. I missed the military parade earlier in the day due to travel, but I did get to see the evening fireworks and Champs de Mars concert at the foot of the Eiffel Tower with my friend Alli and some of her friends.
The theme of the concert was equality, more specifically to advocate tolerance of other nationalities. Their lineup constituted over 50 artists and it was very nice. I really didn't understand what they were singing or saying (minus a Michael Jackson song they played), but I certainly enjoyed the day. At just the concert, 1.2 million people showed up. To put that into perspective, that's larger than the population of Tucson. Fantastic!
The theme of the concert was equality, more specifically to advocate tolerance of other nationalities. Their lineup constituted over 50 artists and it was very nice. I really didn't understand what they were singing or saying (minus a Michael Jackson song they played), but I certainly enjoyed the day. At just the concert, 1.2 million people showed up. To put that into perspective, that's larger than the population of Tucson. Fantastic!
Wednesday, July 13, 2011
Somewhat jealous
On Monday after work Michel took us to dinner. Before we headed into town, we took a 20 minute car ride up to the northern mountains to a fort built at the mountain top. The road was steep and narrow. If I had to guess it was barely wide enough for two Honda Fits to lie side by side. There were tens of very sharp switch backs and it almost seemed impossible to see if another car was coming up or down the switchback until you got pretty close (then again I was sitting in the back seats). Unfortunately the fort is closed on Mondays so we weren't able to get in, but that didn't stop us from exploring a bit. Off to the side of the fort entrance, there's a staircase built into the mountain side that allowed us to reach the very top of the mountain peak. We scaled no more than 3-4 meters and voila, we were at the top.
The cliff face is incredibly steep, it drops straight down right after the edge. Great for paragliders, not so great if you don't enjoy heights. Regardless of the height, the view was absolutely breath-taking, and I mean it. The sun was about 1.5 hours from setting, so there was more than enough light to see the whole city and into the glacial valley. Facing east you could see Mt. Blanc, the highest peak in the Alps, just above the trees; facing south you could oversee all of Grenoble and even some towns more east in the valley; to the west were more mountains. Maybe it was the sun, maybe it was just low hanging clouds, but there was a faint blue haze that defocused objects that were farther in distance, adding to the valley's beauty.
There was a walking trail carved out from the many hikers making a dirt path through the lush greenery. Outside of this 15 inch dirt road, you had plants with yellow and purple flowers, large rocks, trees and still active insects (I saw some flies, bees, and ants). Heck, the bees were so busy with the pollen they didn't even notice us. The trail stopped at a gap in the mountain top, so that's where we stopped. A bit more east though, and across the gap, there was a path built into the mountain side with a passage way that cut through the solid rock. Apparently it extends for miles. That's when it hit me; there aren't close places with such beauty, history, and sights in the U.S. I don't mean the U.S. doesn't have such places, they just aren't normally a 20 minute drive up the mountainside from a well-populated city. And that, is why I'm somewhat jealous.
From here, we walked back to the car, but we didn't go into town immediately. We noticed some hikers walking up an even higher cliff than we were previously on and so we decided to follow suit, even though I wasn't wearing the right shoes (just a pair of sandals). The adventure started out down a hill side with various size stones. Some were about the size of a baseball, others grapefruit-size. At the bottom, we paralleled what seemed to be a man-made moat. Odd, yes, I wouldn't expect a moat on a mountaintop. Interestingly, parallel to the length of the moat, and situated in the center of the moat side, was a small jail-like housing. On our way back to the car we looked inside and on the wall there was a sign. Michel translated and apparently the jail-like place housed cannons of sorts. If intruders tried to get across the moat, they were fired at.
The moat ended and a path leading to this new mountaintop started. We made it up without too much trouble. The hikers we saw earlier were having an evening picnic with the sun set. They had carried up a case of wine and laid out a blanket on the ground. I saw what looked like a pasta salad with chunks of tomato, though I couldn't really tell. They took some pictures for us and we did they same for them. It was very fun. We stayed up there, for about 10 - 15 minutes, then decided to return to town for dinner. By the time we returned to the car, it was about 8:15PM.
Dinner was yummy. It was three courses for 27 euros. For my first course, I had a salad with fried cheese and thick slices of a prosciutto-like meat, then rabbit with a bed of vegetables for my second course. I've never had rabbit before. It didn't taste "gamey" at all, and was very lean. I think I enjoyed the vegetables and the sauce they used a bit more than the rabbit meat. Then for desert I got sorbet. It was a good meal for the end of the day.
Fort St. Eynard
On Monday, our host, Dr. Michel Vivaudou – Head of the Channels Group at IBS – took us for a short trip up to Fort St. Eynard (or here). We had seen the view of the city from Le Bastille and it was stunning, however, it did not prepare us for the amazing view of the city and region found from Fort St. Eynard. The trip up through La Tronche and surrounding suburbs around Grenoble was beautiful. Upon arriving at the fort, we took a short walk up to the “edge”. From the edge you can see Mont Blanc, as well as most other key mountains and regions in that surround Grenoble. It was stunning and the pictures that will be posted below do not do this view justice (in all fairness, I only took my cell phone).
The fort is situated at the top of one of the mountains to the north of Grenoble and there is a sheer face that has a vertical drop >1000 m (I think, it actually seemed higher so I’ll have to check the stats). It was a stunning view and an even more stunning fete to think that the Fort was built atop the mountain over 100 years ago with little modern machinery. We took another short hike to the other side of the fort to see a slightly different angle including Le Bastille, which from this height looked rather small.
Afterwards, we headed to Centre Ville Grenoble (downtown) to have a very nice French dinner and enjoy the company of our host. I’ve said many times on this blog how lucky we were to have such good collaborators and hosts, and every time I’ve meant it. We are very grateful for all that they have done to make us feel welcome both in the lab and out. I hope to be able to return the favor soon!
A view over the edge. It's a LONG drop |
Grenoble from Ft. St. Eynard |
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Au revoir
It is with a bit of sadness that I leave Grenoble to return back to the US. I am very excited to see my family again and to return to my “real job” but the time in the lab here and the relationships that have been established have been very memorable and I am anxious to continue our work. A quick note of thanks again to our hosts and lab mates, particularly Dr. Christophe Moreau and Dr. Michel Vivaudou. So for now I say, “au revoir” to Grenoble (or maybe “à bientôt” would be a better choice of words).
Tuesday, July 12, 2011
Marseille, You Say?
Last Friday (July 8), Mark and I decided to head to the Mediterranean Port city of Marseille. I have wanted to see Marseille for some time, as it came highly recommended by a friend. We booked the train and headed down Friday evening on the TGV (the fast train). The TGV travels >250 km/hr and can go faster, or so I’m told. We arrived in Marseille about 2.5 hours later with big ambitions. I should have probably been skeptical when our French friends in Grenoble would only say, “Marseille, huh? It’s in the south of France”. I wasn’t sure what that statement was supposed to mean but in retrospect, we should have read between the lines.
Marseille is a port city with a stunning harbor. It is the primary route of ferry traffic and is the port of entry for most of the goods and peoples coming from the Mediterranean region. It is also the port of entry for a large number of cruise ships. As we left the train station headed to find our hotel, we quickly realized we were not in Grenoble anymore. While Grenoble is a relatively small, easy-going city, Marseille is more reminiscent of a large US metropolis. It is, after all, the second largest city in France. Our hotel was right in the city center, about 10 min walk from the train station. In theory that was a great idea. In practice, the city center was more than a bit frightening at times.
After hotel check-in, and dealing with a security issue that I’ll spare the details of, we headed down to the harbor to have some dinner and enjoy the sea. It turned out to be a nice evening and the harbor is a very active and interesting place.
The next morning we made a tour of some of the more popular sites in the city. Notre Dame de la Garde, Palais Pharo and Palais de Longchamps. There are some stunning sites in Marseille and you are never far from the coastline, which is quite nice. After touring the city for the day, we took the “slow” train back to Grenoble through the French Alps, where we saw probably the most stunning scenery of the trip (up until that point).
After returning to Grenoble we were talking with our friends in about our trip and again we heard (more than once), "well that’s Marseille, it’s in the South of France.”
Palais de Longchamps in Marseille. You have to see it to believe it. |
Arc de Triomph in Marseille |
A view of Marseille from Notre Dame de la Garde |
A view of Marseille from Notre Dame de la Garde |
A view of Marseille from Notre Dame de la Garde |
An old US tank in the streets of Marseille. |
It is apparently perfectly acceptable to park on the sidewalks in Marseille. |
Fort St. Nicholas - One of several old forts that guarded the harbor. |
I had to go to Marseille to see the same things I have in the back yard. |
The harbor in Marseille. |
Simple is better
Today was a more science filled day. We wanted to see if partitioning in polymerizable monomers would increase the stability of an ooctyes plasma membrane. The plasma membrane is held together by weak van der waals interactions, and something as simple as transferring a piece of membrane across an air-water interface is enough to disturb the bilayer structure. If we want to use ICCR's in a biosensor platform, we need to satisfy several criterion, two of which our lipids research hopefully fulfills: we must 1) provide a hydrophobic environment that, for the most part, mimics the protein-lipid interactions found in a real plasma membrane such that the ICCR correctly folds, and 2) provide a membrane with extended lifetime for longer term use in, e.g. diagnostics or high throughput screening of drugs.
In an ooctye, a large amount of structural stability is provided by the vitelline membrane. In our experiments, we decided to remove this membrane and directly partition monomers into the plasma membrane. That part, and the polymerization was easy, but, the big question was, how would we quantitatively determine whether the oocyte had increased structural stability?
Generally, ooctyes have a spherical shape, which is relatively easy to deform, especially once the vitelline membrane (VM) is removed. If you were to transfer the VM-less oocyte to a paper towel, the surrounding water would quickly soak up, and the oocyte would flatten out like a pancake. In contrast, if the VM is still attached, the oocyte still has some structure even after the surrounding water is removed. To give an idea of it's shape, picture a water droplet you've put on your desk; it's somewhat round, but not completely. We could use this physical test to observe structural stability, comparing non-peeled ooctyes, peeled oocytes, and polymerized oocytes. Alternatively, we could try chemical tests, exposing oocytes to different solvents.
Christophe and I tried both physical and chemical tests. To dry the surrounding water, we used a piece of paper and a paper towel. The paper was much slower at absorbing water, so we discontinued its use. The towel was useful. It absorbed water quickly. However, it was hard to discern the oocyte shape. From there, we moved onto chemical tests. We tried ethanol, soapy water, decane, SDS solutions, and chloroform. The chloroform was funny, because it immediately turned the low density polyethylene petri dish into a goopy mess. As a chemist, I should have known that would happen, but in the spirit of investigation, I was mostly caught up in testing the stability.
Suprisingly, the oocyte can handle many chemical insults. They withstood ethanol; chloroorm and decane removed some of the lipids on the dark side of the oocyte, but did not compromise its stability; SDS and soapy water caused the oocytes to disintegrate, but only after an extended period (20 minutes). Certainly these tests should be performed again to ensure we obtain the same results.
From there, we decided that an air-water interface transfer provided the easiest to interpret results, it was simply a matter of how to replicate the transfer without the need of a towel. Christophe took some oocytes sitting in a petridish of water and removed the water with a pipette. Voila!! The oocytes behaved similar to the paper towel; the peeled oocytes flattened like a pancake and the non-peeled oocytes kept their shape. The polymerized oocytes were a bit harder to discern, and we'll try again. In the end, the best test was the simpliest.
In an ooctye, a large amount of structural stability is provided by the vitelline membrane. In our experiments, we decided to remove this membrane and directly partition monomers into the plasma membrane. That part, and the polymerization was easy, but, the big question was, how would we quantitatively determine whether the oocyte had increased structural stability?
Generally, ooctyes have a spherical shape, which is relatively easy to deform, especially once the vitelline membrane (VM) is removed. If you were to transfer the VM-less oocyte to a paper towel, the surrounding water would quickly soak up, and the oocyte would flatten out like a pancake. In contrast, if the VM is still attached, the oocyte still has some structure even after the surrounding water is removed. To give an idea of it's shape, picture a water droplet you've put on your desk; it's somewhat round, but not completely. We could use this physical test to observe structural stability, comparing non-peeled ooctyes, peeled oocytes, and polymerized oocytes. Alternatively, we could try chemical tests, exposing oocytes to different solvents.
Christophe and I tried both physical and chemical tests. To dry the surrounding water, we used a piece of paper and a paper towel. The paper was much slower at absorbing water, so we discontinued its use. The towel was useful. It absorbed water quickly. However, it was hard to discern the oocyte shape. From there, we moved onto chemical tests. We tried ethanol, soapy water, decane, SDS solutions, and chloroform. The chloroform was funny, because it immediately turned the low density polyethylene petri dish into a goopy mess. As a chemist, I should have known that would happen, but in the spirit of investigation, I was mostly caught up in testing the stability.
Suprisingly, the oocyte can handle many chemical insults. They withstood ethanol; chloroorm and decane removed some of the lipids on the dark side of the oocyte, but did not compromise its stability; SDS and soapy water caused the oocytes to disintegrate, but only after an extended period (20 minutes). Certainly these tests should be performed again to ensure we obtain the same results.
From there, we decided that an air-water interface transfer provided the easiest to interpret results, it was simply a matter of how to replicate the transfer without the need of a towel. Christophe took some oocytes sitting in a petridish of water and removed the water with a pipette. Voila!! The oocytes behaved similar to the paper towel; the peeled oocytes flattened like a pancake and the non-peeled oocytes kept their shape. The polymerized oocytes were a bit harder to discern, and we'll try again. In the end, the best test was the simpliest.
Sunday, July 10, 2011
Nearing the End of the First Journey
As my last week in Grenoble begins, I look back on our time here with great satisfaction. The quality of the scientific interactions and the personal relationships that have been developed are higher than I would have ever dreamed. We knew from previous works and reputation that the Channels Research Group at IBS performed very high quality science. What we didn’t know was what high quality individuals they are. Our colleagues here have proven yet again that you can be exceptional scientists and at the same time be wonderful people.
From the moment we arrived in Grenoble Dr. Christophe Moreau has gone beyond all expectations to make our time here productive, but even more so, to make it fun. Group leader Dr. Michel Vivaudou has welcomed us into his lab and has shared his science with us in an open and unfettered manner, allowing us to understand what is really being done in the lab on a day by day basis. The research synergy between our labs is almost immeasurable and should position us to work together for the foreseeable future. Overall, it has been demonstrated time and again that we made the right choice in coming to Grenoble and working with our colleagues here.
Though my time here is coming to an end this week, Mark will continue here for another 4 weeks, continuing to strengthen our collaboration and helping us collect the data necessary for the two proposal submissions that we have planned for the coming months.
Some Science
It seems to rain mostly at night here in Grenoble. Even though dark, ominous clouds visibly creep across the northwestern mountains, it never seems to rain substantial until nighttime. It's kind of like an empty threat that looms throughout the day. But right now there are thunderstorms in the not so distant mountains and I can hear rain outside. OH, there's a flash in the sky! These storms are as spectacular as the ones' in Tucson, but they are still nonetheless fun to watch if they are "your-sort-of-thing." Either way, it's a good chance to sit down and contemplate on some of the new sciences I've been introduced to here working with the Vivaudou group. I can't say I'm an expert - in training I'm more knowledgeable about marine chemistry (undergraduate work) and am now becoming more knowledgeable about lipids, sensors, experimental design, etc. - but at least I can provide a cursory discussion of the technique.
In the Vivaudou lab, ICCR's are expressed in Xenopus oocytes (these are frog eggs). Frog's from the Xenopus genus are relatively large frogs with claws. Their eggs are routinely used in protein expression studies because one can inject mRNA or exogenous DNA coding for a particular protein of interest and get protein expression (pretty cool if you ask me). See the citation below for the fundamental paper. The are a number of interesting consequences, such as the ability to analyze isolated receptors or ion channels; mutating receptors or channels and then expressing them in order to understand structure and function; and study receptor-ligand interactions.
The Xenopus oocyte are about 1 mm in diameter and are thus visible to the naked eye. There are different stages of ooctyes, but researchers primarily use stage V and VI. Here's a site with some good pictures of frogs and eggs. In stage V and VI, the oocyte has two distinct hemispheres, one corresponding to the animal pole (dark) and one corresponding to the vegetal pole (light). The vitelline membrane, a thin, clear membrane, encases the two hemispheres and provides the oocyte with some structural support. Further encasing the vitelline membrane is the follicle cell layer, which carries blood vessels. In a way, they remind me of miniature pearl tapioca.
That's all for now, more to come later.
Gurdon, J.B., Lane, C.D., Woodland, H.R., Marbaix, B. Use of frog eggs and oocytes for the study of messenger RNA and its translocation in living cells. Nature (1971), 233, 177-182.
In the Vivaudou lab, ICCR's are expressed in Xenopus oocytes (these are frog eggs). Frog's from the Xenopus genus are relatively large frogs with claws. Their eggs are routinely used in protein expression studies because one can inject mRNA or exogenous DNA coding for a particular protein of interest and get protein expression (pretty cool if you ask me). See the citation below for the fundamental paper. The are a number of interesting consequences, such as the ability to analyze isolated receptors or ion channels; mutating receptors or channels and then expressing them in order to understand structure and function; and study receptor-ligand interactions.
The Xenopus oocyte are about 1 mm in diameter and are thus visible to the naked eye. There are different stages of ooctyes, but researchers primarily use stage V and VI. Here's a site with some good pictures of frogs and eggs. In stage V and VI, the oocyte has two distinct hemispheres, one corresponding to the animal pole (dark) and one corresponding to the vegetal pole (light). The vitelline membrane, a thin, clear membrane, encases the two hemispheres and provides the oocyte with some structural support. Further encasing the vitelline membrane is the follicle cell layer, which carries blood vessels. In a way, they remind me of miniature pearl tapioca.
That's all for now, more to come later.
Gurdon, J.B., Lane, C.D., Woodland, H.R., Marbaix, B. Use of frog eggs and oocytes for the study of messenger RNA and its translocation in living cells. Nature (1971), 233, 177-182.
Thursday, July 7, 2011
Affordable Travel
Once again, I'm amazed at how affordable student travel is in Europe. Craig and I went to the train station today to purchase tickets down to Marseille, a seaside city in southern France, and the ticket woman offered me a student train pass. It allows me to get tickets with discounts ranging from 25-60%. I have one thing to say to that - SWEET!
Praying for Rain
Today, I prayed for rain! Why, you ask? Today was the day for Via Ferrata (a different link to this particular via ferrata is here). It is very difficult for me to explain this with the clarity that it deserves so I really suggest you visit one of the excellent websites on the subject such as this one, this one or this one. In short, a Via Ferrata is a “path” (I use this term very loosely) that goes up the side of the mountain and then across the rock face consisting of rock holds, iron bars and most importantly a safety cable that must be used at all times. There are some iron spikes in rock faces (these are the easier parts) with various forms of torture including single line cable bridges, rock gaps, etc. Historically, it developed in the Austrian Alps and, as it’s considered to be a bit easier than rock climbing, it allowed people to reach new heights (literally). In the early 1900’s the Italians built Via Ferrata routes through the mountains to transport troops, artillery, etc. during war time. In much of the late 20th and early 21st centuries, Via Ferrata has become an adventure sport. France is probably the modern capital of the sport and the French are among the most active participants.
When we first arrived in Grenoble, Christophe took us to the park to show us the Via Ferrata route to Le Bastille. It is in two sections and according to ViaFerrata.org (I looked this up AFTERWARDS, thank goodness) the first section, the one we did, is ranked between difficult and very difficult on the various sites, while the second section is ranked extremely difficult, the highest ranking. Christophe had the idea that we should experience this for ourselves. In my younger (and thinner) days, I had no problems with such activities and actually really enjoyed them. Of course those who know me, know that I’m no longer younger or thinner. At any rate, this is something that I really, deep down wanted to do, but also something that I doubted I would be able to accomplish and thus my pride would be wounded in front of my new Alpine friends and colleagues, not to mention the very real and very serious possibility of being stuck on the side of a mountain. If you could see this rock face, you would understand why I was concerned. According to the statistics, its 120 m high (I think this might be a bit off as it seemed less) and 250 m long – I believe this value.
So back to rain – I knew the only thing that would save my pride was rain. It’s just too dangerous to do in the rain with a slippery granite face. I’ve been watching the forecast all week and there has been rain predicted for Thursday, our chosen day. At 11:45 today, my prayers were answered – it began to rain and my pride (and for that matter the rest of me) would be intact. However, the rain was short lived and before noon the sun was out again. So, Via Ferrata, here we come!
We arrived at the park and “saddled up” in our safety harnesses, etc. Then we took a practice loop through the introductory course to make sure we knew what we were doing (the answer is still probably no, for me at least, though I have to admit Mark looked like a pro). This loop was about 15 m high and 15 m across before descending (the really tricky part). Then, it was off to the real “trail”.
I’m not sure if it was the best thing or the worst thing, but Mark and I had no idea the path that the “trail” would take or when it would end. An hour later and a lot of hard work hanging over the side of a rock face that was very high above the park below and we reached the top (of the first section). A very important thing to know about Via Ferrata (at least this one) is that there is NO turning back (it’s a one way adventure) and there’s NO opportunity to quit along the way. There is quite literally, only one way out so when you do this, you are ALL IN. To be sure, there were times I wondered if I would make it but we plugged on and made it to the end. It was the single most exhilarating and exhausting thing that I have ever done.
Afterwards, it was off for a very well deserved lunch. I must thank our hosts Christophe and Michel, as well as our colleague Nico, for taking us on this extreme adventure. It was certainly a first for me and the experience of a lifetime. I look forward to one day trying the second section (maybe on sabbatical).
I am very glad it did not rain!!
Note, it is extremely difficult to take pictures while hanging for dear life over a large drop but our host Michel Vivaudou managed to do so and we will post them when he provides them. For now I have provide a few taken with my cell phone when I wasn't clinging with all my might.
Christope leading the way on the "training run".
Nico and Mark on the "training course".
A view from the cable bridge of the park below.
A few other climber following our path - this photo puts into perspective where we had come from.
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