Author: Sara Klink

DNA Amplification Using Body Heat, No Instrument Required

Posted on by Sara Klink

Cartoon by Ed Himelblau
Cartoon by Ed Himelblau Copyright Ed Himelblau.
When I was in the lab, there was more than a few times I held tubes in my hand (maybe even under my arm) to make them thaw faster, especially reaction buffers. However, I never considered whether this could be a strategy for actual incubation although humans run at about 37°C and many restriction enzyme reactions proceed most efficiently at 37°C. But research published in PLOS ONE by Crannell, Rohrman and Richards-Kortum took this idea and decided to experiment with the possibility of eliminating an instrument-based DNA amplification. Continue reading “DNA Amplification Using Body Heat, No Instrument Required”

Improving Cancer Drug Screening with 3D Cell Culture

Posted on by Sara Klink

Differential contrast image of HCT116 colon cancer spheroid grown in a 96-well hanging-drop platform after seeding with 800 cells. Copyright Promega Corporation.
Differential contrast image of HCT116 colon cancer spheroid grown in a 96-well hanging-drop platform after seeding with 800 cells. Copyright Promega Corporation.
Tissue culture using primary or cultured cell lines has long been a mainstay of testing compounds for inhibiting cell growth or promoting apoptosis during screening for cancer drugs. However, the standard culture conditions result in monolayers of cells, dividing and growing across the bottom of a well, plate or flask in a single layer. The drawback of this technique is that organisms do not come in monolayers; a three-dimensional (3D) spheroid is closer to the in vivo state, especially if the spheroids are made up of more than one cell type like tumors in multicellular organisms. Even more beneficial would be using 3D cultured cells in high-throughput screening to facilitate compound profiling for target effectiveness and cytotoxicity. In a recent PLOS ONE article, researchers used normal and breast cancer cells both in monoculture and coculture to test a set of compounds and found results differed between 2D and 3D cultured cells. Continue reading “Improving Cancer Drug Screening with 3D Cell Culture”

Promising Treatment for Marburg Virus Hemorrhagic Fever

Posted on by Sara Klink

I admit to some trepidation about the diseases that may be harbored in my backyard. For example, do the mice in my yard and, despite my and my cats’ efforts, in my house carry deer ticks that harbor the bacterium Borrelia burgdorferi, which causes Lyme disease? Should I be keeping an eye on the vitality of the birds around my property and density of my local mosquito population for potential risk of West Nile Virus transmission? As troublesome as these infections can be, mortality is low for infected humans. Contrast that with the mortality rate of up to 90% for the filoviruses Ebola and Marburg. I find it easy to dismiss these viruses because the reservoir (asymptomatic host) is not in the Upper Midwest but rather Africa, but the tragedy of the Ebola outbreak in the West African countries of Liberia, Sierra Leone and Guinea demonstrates the number of lives lost in an epidemic. Currently, there is no therapy or vaccine to treat these deadly viruses other than transferring antibodies from survivors to those infected. Therefore, the article in Science Translational Medicine about an antiviral treatment that protected macaques injected with a lethal dose of Marburg virus was welcome news.

Continue reading “Promising Treatment for Marburg Virus Hemorrhagic Fever”

Investigating the Role of Hair Proteins in Fighting Cancer

Posted on by Sara Klink

Human Hair 40X Magnification.
Human Hair 40X Magnification. Taken at Strathclyde University Forensic Science Department by Edward Dowlman
Many scientists seek anticancer compounds derived from plants (e.g., black raspberry extract). What about something a bit closer to home: byproducts from humans? Markowicz et al. were interested in the effects that hair degradation products could have on cancer cells, specifically melanoma.

Hair from two donors, a gray-haired elderly man and a young brunette woman, were collected after a haircut and separately processed by activation in sodium hydroxide prior to digestion with pepsin, a protease that cleaves at the C-terminus of phenylalanine, leucine, tyrosine and tryptophan. The digested fragments were extracted, frozen and dried down. The remaining unsolubilized material was dried, ground and redigested with pepsin, yielding two samples of pepsin digests from each hair sample. The final pepsin digests were suspended in 70% ethanol. Continue reading “Investigating the Role of Hair Proteins in Fighting Cancer”

Can Fruit Flies Glow in the Dark?

Posted on by Sara Klink

Fruit fly. Image from morguefile.
Question: How is a fruit fly like a firefly? No, this is not an obvious answer (their names start with the letter “f”) or the beginning of a bad entomology joke. These two organisms may both be winged insects, but as it turns out, what makes the firefly light show such a special treat on summer evenings is something that fruit flies, the bane of the kitchen in the summertime and annoyance for labs near Drosophila researchers, can mimic with a little help from a synthetic luciferin substrate as reported in PNAS. Continue reading “Can Fruit Flies Glow in the Dark?”

Uncovering the Life and Death of a Mummy

Posted on by Sara Klink

Frontal view of the mummy
Panel A of Figure 1 shows the frontal view of the mummy. Panzer, S. et al. (2014) Reconstructing the Life of an Unknown (ca. 500 Years-Old South American Inca) Mummy – Multidisciplinary Study of a Peruvian Inca Mummy Suggests Severe Chagas Disease and Ritual Homicide. PLoS ONE 9(2): e89528. doi:10.1371/journal.pone.0089528

Deciphering how an ancient person lived and died is based heavily on the context of the buried body or mummy, including the soil around the gravesite, artifacts present in the grave and if nothing else, the location of the remains. What happens when there is no context? With skeletal remains or even bone fragments, which is primarily what is found at many burial sites, there is some information that can be derived but mummies that include tissue as well as bone offer a greater opportunity to learn about a deceased individual’s life. A recently published PLOS ONE article of a bog body identified using analyses across several scientific fields demonstrates how we can uncover the story of a person who lived several centuries ago based on her mummified remains. Continue reading “Uncovering the Life and Death of a Mummy”

Fun with Chemistry for Valentine’s Day

Posted on by Sara Klink

Image credit: Morguefile

Looking for last-minute gift ideas? Wondering what chemistry has to do with Valentine’s Day? The chemists of the American Chemical Society (ACS) have curated a web page called Valentine’s Day Chemistry that offers gift ideas (for example, make a crystal heart using pipe cleaners, borax and hot water), explains the chemistry behind chocolate and flowers, shows a video that equates chemical bonding to people interacting at a party and more. The links and videos offer something for everyone, whether you want to have fun with friends and family of all ages or just want to learn something new about chemistry.

Happy Valentine’s Day!

Amino Acid Analogs as Possible Cancer Drugs

Posted on by Sara Klink

HeLa cells stained with Hoechst 33258. By TenOfAllTrades (From English wiki 1.) [Public domain], via Wikimedia Commons
Scientists look in unusual places for potential anticancer treatments. I have reviewed papers that investigated the possibility that dandelion root may harbor anticancer treatments, milk fat may moderate cancer metastasis and the effects of chemotherapy, and black raspberry extract may even prevent cancer. Sometimes, research avenues come down to an observation about what a tumor cell needs to grow and exploring the idea that molecular analogs might be a tool to block cancer growth. For the work reported in Drug Design, Development and Therapy, analogs of the amino acid glycine, specifically glyphosate and aminomethylphosphonic acid (AMPA), the degradation product of glyphosate, were used to explore this idea in cancer cell lines. Continue reading “Amino Acid Analogs as Possible Cancer Drugs”

When Did Cats Become Companion Animals?

Posted on by Sara Klink

Is that a mouse? Image source: morgueFile.

I am unabashedly a cat person, heavily influenced, I suspect, by the ever-fluctuating population of cats that roamed the family farm. Most of these outdoor cats were skittish around humans, but sometimes there were friendly female cats with a litter of kittens that were fun to chase, pick up and stroke. While the farm’s clowder of cats would eagerly await table scraps my mom would put out in the evening, there was plenty of opportunity for the felines to hunt vermin around the farm. It is this function—rodent control—that may be the reason that many of us share our homes with cats. One hypothesis to explain the association between cats and humans is rodents were stealing from human grain stores and cats could control rodent populations. However, there was not much data to confirm this hypothesis. Recent archeological evidence from China seems to support this view of cat domestication as reported in the Proceedings of the National Academy of Sciences. Continue reading “When Did Cats Become Companion Animals?”