Postcards from the Northern Roman Empire

Some of the thin wood tablets found at Vindolanda in Northumberland, England. Image Copyright The Vindolanda Trust.

Correspondence whether via postcard or letter has been a method of human communication likely since people became literate. Old letters and postcards have been uncovered in attics, basements and garages, offering depth and richness to historical events or adding context to how humans lived in the past. But what about finding correspondence from more than a few hundred years ago?

Interestingly, archeologists were excavating in a Roman fort just south of Hadrian’s Wall and discovered well-preserved thin slices of wood with ink writing dating to the 1st century. While these 25 postcard-sized correspondence, found in a line about 3–4 meters long, are just the latest uncovered at the Vindolanda fort, the documents add to the history of Romans in Britain.

Many of the newly discovered wooden wafer postcards seemed to contain complete messages and could be read without the need for infrared photography. This treasure “hoard” of ancient Roman writing tablets offer insights such as a man named Masclus asking for leave. His previously discovered correspondence also from the Roman fort at Vindolanda included asking his commanding officer to supply more beer to his outpost.

The announcement of these 25 new Roman messages by the sponsors of the fort excavation are only preliminary overview of the find. In fact, archeologists are working on conserving and deciphering messages on the wooden tablets and plan on using infrared photography to reveal if there is any more writing on these postcards from the past.

Read more in the Vindolanda Trust Press Release.

Promega Third Party Forensic-Grade Certification

Promega has become the first major forensic manufacturer to achieve third party certification of the published ISO 18385 standard to minimize the risk of human DNA contamination in products used to collect, store and analyze biological material for forensic purposes.

On February 2, 2016, ISO 18385:2016 was published as the first international standard specific to the forensic manufacturing community. Since the standard was published, companies have begun to self-declare that they comply with the ISO standard. Some companies have gone a step further and reached out to Certification Bodies to provide an unbiased and independent assessment their compliance to ISO18385 through a third-party audit.

When consumers see an ‘ISO 18385 Forensic Grade’ labeled product, it should inspire confidence that the product was produced in accordance with a minimum set of criteria common to all manufacturers.

So what are you actually getting in a Forensic Grade labeled product? Continue reading

Cytotoxicity Testing of 9,667 Tox21 Compounds using Two Real-Time Assays by Promega

A recent paper in PLOS One demonstrated real-time cytotoxicity profiling of approximately 10,000 chemical compounds in the Tox21 compound library, using two Promega assays, RealTime-Glo™ MT Cell Viability Assay and CellTox™ Green Cytotoxicity Assay. This is exciting to me, a science writer working at Promega; exciting because it’s tricky figuring out how to write about the utility of our products without sounding like an evangelist.

I don’t know about you, but I tend to shut out evangelists and their messages.

Instead of me telling you about real-time viability and cytotoxicity assays from Promega, here is an example of their use in Tox21 chemical compound library research.

What is the Tox21 compound library?
As described in the article by Hsieh, J-H. et al. (2017) in PLOS One:
“The Toxicology in the 21st Century (Tox21) program is a federal collaboration among the National Institutes of Health, including the National Toxicology Program (NTP) at the National Institute of Environmental Health Sciences and the National Center for Advancing Translational Sciences, the Environmental Protection Agency, and the Food and Drug Administration. Tox21 researchers utilize a screening method called high throughput screening (HTS) that uses automated methods to quickly and efficiently test chemicals for activity across a battery of assays that target cellular processes. These assays are useful for rapidly evaluating large numbers of chemicals to provide insight on potential human health effects.” Continue reading

ISHI 28 Workshop: Towards Better Solutions for Body Fluid Identification

Although techniques for DNA analysis of forensic samples have evolved considerably in recent years, the methods used to identify particular body fluids in forensic casework have remained relatively unchanged over the same time period. This year, one of the workshops offered at the International Symposium on Human Identification (ISHI; to be held in Seattle from October 2-5), will be focused on current and emerging techniques for body fluid identification that promise change—applying molecular genetics and proteomics analysis to the problem of body fluid identification.

According to the ISHI conference website, the purpose of the workshop is to “highlight current serology methods using critical case examples while also exploring emerging methods that could complement or replace these traditional techniques”. Continue reading

Use of HIC high resolution chromatography and elastase for bottom up proteomics

One of the key applications used to characterize single or complex protein mixtures via bottom up proteomics is liquid chromatography−tandem mass spectrometry (LC−MS/MS).
Recent technical advances allow for identification of >10 000 proteins in a cancer cell line. On the peptide level chromatography methods, like strong cation exchange (SCX)
and hydrophilic interaction chromatography (HILIC), as well as high-pH reversed phase chromatography have been employed successfully. Because of its robustness
and ease of handling, the classical and still widely used approach for protein fractionation prior to LC− MS/MS is gel-based separation under denaturing conditions (SDS-PAGE).
Hydrophobic interaction chromatography (HIC) is a robust standard analytical method to purify proteins while preserving their biological activity. It is widely used
to study post-translational modifications of proteins and drug−protein interactions.  HIC is a high-resolution chromatography mode based on the interaction of
weakly hydrophobic ligands of the stationary phase with hydrophobic patches on the surface of the tertiary structure of proteins. By employment of high concentrations
of structure-promoting (“kosmotropic”) salts, proteins in HIC retain their conform

In a recent publication, HIC was used to separate proteins, followed by bottom up LC−MS/MS experiments (1).  HIC was used to fractionate antibody species
followed by comprehensive peptide mapping as well as to study protein complexes in human cells. The results indicated that HIC−reversed-phase chromatography (RPC)
mass spectrometry (MS) is a powerful alternative to fractionate proteins for bottom-up proteomics experiments making use of their distinct hydrophobic properties.

An additional observation noted that tryptic digests of the antibody used in the study yielded a protein coverage of 56% for the light chain and 63.2% for the
heavy chain. A consecutive proteolytic digestion protocol combing on-filter trypsin and elastase digestion drastically improved sequence coverage of
both light (100%) and heavy chains (99.2%).

Reference
1. Rackiewicz, M. et al. (2017) Hydrophobic Interaction Chromatography for Bottom-Up Proteomics Analysis of Single Proteins and Protein Complexes. J.Proteome.Res. 16, 2318–23.

Searching for Secrets in Single Cells

There has been a lot of effort recently to perform whole genome sequencing, for humans and other species. The results yield new frontiers of data analysis that offer a lot of promise for groundbreaking scientific discoveries.

One objective of human genome sequencing has been to identify sources of disease and new therapeutic targets. This movement has opened the door to create personalized medicine for cancer, whereby the genetic makeup of an individual’s tumors can be used to determine the most effective drug intervention to administer.

Interest in studying the characteristics unique to individual cells seems obvious when considering the function of healthy cells versus tumor cells, or brain cells compared to heart cells. What has surprised scientists is the realization that two cells in the same tissue can be more different from each other, genetically, than from a cell in another organ.

For example, a small number of brain cells with a specific mutation can lead to some forms of epilepsy while healthy people may also carry cells with these mutations, but too few to cause disease. The lineage of a cell, where it came from and what events shaped its development, ultimately determines what diseases can exist.

Continue reading

A Successful Launch for Biotechnology: The Basics for Middle School Teachers

Megan Wagner (left) and Katie Aliota, science teachers from Cardinal Heights Upper Middle School in Sun Prairie, WI; load an agarose gel with colored dyes.

Megan Wagner (left) and Katie Aliota, science teachers from Cardinal Heights Upper Middle School in Sun Prairie, WI; load an agarose gel with colored dyes.

Today’s blog is jointly written by guest blogger  Peter Kritsch, Biotechnology and Biology Teacher at Oregon High School and contributor Barbara Bielec. K-12 Program Director at the BTC Institute.

The BTC Institute has offered two graduate-level courses for high school teachers for many summers.  Biotechnology: The Basics and Biotechnology: Beyond the Basics have become very popular and are also drawing the interest of middle school teachers.  So, this June we piloted a new 3-day course designed specifically for them.  Representing different schools and districts, eight teachers learned how to extract DNA from strawberries, pour and run agarose gels, identify a taste gene, and received information on lots of resources to use with their students.

Through the BTC Institute’s Biotechnology Teacher Academy, these courses are offered at no cost and $300-$500 stipends are available.  A main Academy goal is to provide high quality professional development opportunities that prioritize content that participants can smoothly incorporate into their classrooms.   Our commitment to stipends is generously supported by the Wisconsin Space Grant Consortium (WSGC), Promega Corporation, Madison College and the BTC Institute.  (All three courses are offered for graduate credits from Edgewood College, and Viterbo University also offers credits for the two geared to high school teachers.)

The importance of this approach is affirmed by Sherry Jacobsen (Kromrey Middle School in Middleton, WI):

This [course] is such a gift to teachers!  Many times we aren’t treated as professionals so it was nice to be treated as a professional without a high personal cost.  I love how the course is so practical.  Many courses are only in theory and no application.  I can take so many useful ideas with me.

Biotechnology is making its way into the middle school classroom. With access to the BTC Institute’s Equipment Loan Program, teachers can check out micropipettes, gel boxes & power supplies, an ultraviolet light box and other equipment for up to two weeks.  Course participant Amy Reimer (Core Knowledge Middle School in Verona, WI), has already taken advantage of this program and noted that it was “great to review procedures” through the course and plans to borrow equipment again this coming year. Continue reading

Promega Tech Tours 2017: The Power to Solve for the Forensic Community

Governor John Bel Edwards of Louisiana made an appearance at the Promega Technology Tour in Baton Rouge. Pictures courtesy of Forensic Scientists at the Louisiana State Police.

2017 finds Promega on the road visiting cities all across the United States. This year we are presenting workshops from leaders in the forensics community on topics like maximizing success with challenging samples, improving laboratory efficiency and reducing backlogs, and new tools and technologies for the forensics laboratory. This highly popular workshop series is a great way to learn from your peers about new techniques and workflows and network with other forensics experts in your region.

There are several more tours left between now and the end of 2017. Find out if we are coming to a city near you and register today!

Just in Time for Wisconsin’s Invasive Species Month: Goats

Invasive kudzu vine

Invasive kudzu vine covering a forest

“In Georgia, the legend says
That you must close your windows
At night to keep it out of the house
The glass is tinged with green, even so
As tendrils crawl over the fields…”
—James Dickey (1)

I grew up in Georgia, where on a hot, humid summer day you could almost hear the hiss of growing vegetation, especially the Kudzu as it climbed over fence posts and encroached upon the roadside, the king of invasive species. In Florida you worry about the alligators along the roadside if you have a flat tire; in Georgia, beware the Kudzu.

Invasive species, animal and plant, are an issue in all ecosytems. Imported from distant (and not-so-distant) areas both by accident and misguided intent, invasive species are species that have escaped the checks and balances of natural competitors and predators that existed in their native habitats. This lack of predation and competition enables them to outcompete and overrun other species.

Kudzu may be one of the most recognized invasive species in the United States, but it’s probably not the worst. The zebra mussel is an aquatic animal that has invaded our waterways in Wisconsin. Oak savannahs and prairie ecosystems in the Midwest United States are threatened by many invasive plant species like garlic mustard and blister parsnip. The Wisconsin DNR lists nearly 150 restricted and/or prohibited invasive plant species in Wisconsin, including Kudzu (2). Continue reading

Five Ways to Explain CRISPR Without Delivering a Lecture

Recently a FaceBook friend of mine (who is not a scientist) shared a video from WIRED Science where the concept of CRISPR is explained at 5 Levels of Difficulty— for a 7 year old, a teenager, a college student, a grad student and a CRISPR expert.

First it was pretty amazing to me that my non-scientist friends are interested enough in learning about CRISPR to share this type of information—perhaps showing just how popular and exciting the method has become. People outside the scientific field are hearing a lot about it, and are curious to know more.

This video does a great job of explaining the technique for all its intended audiences. It also is a nice illustration of how to share information in an easily understandable format. Even with the 7 year old and 14 year old, the information is shared in a conversational way, with everyone involved contributing to sharing information about CRISPR.

Really nice. Here’s the WIRED video:


Continue reading