Tag Archives: pcr

Testing Water for Antibiotic-Resistant Bacteria

Antibiotic-resistant bacteria are an important concern for disease prevention in the future. UA doctoral candidate Victoria Obergh is testing Tucson-area wastewater systems to find out where these bacteria can be found.

In the lab, Victoria Obergh transfers bacterial DNA samples into a tray. A graduate student in the University of Arizona’s Department of Soil, Water and Environmental Science, part of the College of Agriculture and Life Sciences, Obergh works with the samples under a sterile hood sporting an ultraviolet light to kill any unwanted DNA. (more…)

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Exotische Beute

Neben klimatischen Entwicklungen zählt der Einfluss invasiver Arten aus der Tier- und Pflanzenwelt zu den wichtigsten Ursachen für den globalen Wandel. Dr. Anita Juen untersucht die Auswirkungen der Ankunft eines asiatischen Regenwurms auf Räuber-Beute-Beziehungen in einem der ältesten Wälder der Erde in den USA.

Sie lockern das Erdreich auf, kompostieren abgestorbene Pflanzenreste und tragen zu einem „gesunden“ Boden bei: Regenwürmer gelten als Nützlinge und sind in jedem Garten gern gesehene Gäste. Doch bereits seit einigen Jahren beginnt das positive Image dieser Würmer immer stärker zu wackeln. „Einige Arten breiten sich angesichts der verstärkten internationalen Vernetzung auf der ganzen Welt aus und können unter Umständen ganze Ökosysteme verändern“, erklärt Anita Juen vom Institut für Ökologie der Universität Innsbruck. Die Wissenschaftlerin befasst sich mit Themen wie Artenvielfalt in landwirtschaftlich genutzten Flächen oder natürliche Schädlingsregulation und erforscht mithilfe molekularer Methoden Entwicklungen in Nahrungsnetzen. In einem vom FWF geförderten Projekt mit dem Titel „Einfluss invasiver Arten auf Räuber-Beute-Beziehungen“ untersucht die Ökologin am Beispiel der asiatischen Regenwurmart Amynthas agrestis mögliche Konsequenzen dieser Invasion nicht-heimischer Würmer in einem Nationalpark im Osten der USA. Während zahlreiche Studien die teils massiven Auswirkungen auf Bodenstruktur oder Vegetation belegen, ist das Wissen über potenzielle Veränderungen in Nahrungsnetzen bisher sehr lückenhaft. „Regenwürmer spielen in der Nahrungskette eine wichtige Rolle und stehen am Speiseplan zahlreicher Arten“, sagt Juen. „Ich habe mir die Frage gestellt, ob das Eintreffen einer neuen Spezies Auswirkungen auf das Beuteschema räuberisch lebender Tiere hat“. (more…)

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The final nail in the Jurassic Park coffin

It is hardly possible to talk about fossil insects in amber without the 1993 movie Jurassic Park entering the debate.

The idea of recreating dinosaurs by extracting DNA from insects in amber has held the fascination of the public for two decades. Claims for successful extraction of DNA from ambers up to 130 million-years-old by various scientists in the early 1990s were only seriously questioned when a study at the Natural History Museum, London, was unable to replicate the process. The original claims are now considered by many to be a text-book example of modern contaminant DNA in the samples. Nonetheless, some scientists hold fast to their original claims.

Research just published in the journal The Public Library of Science ONE (PLOS ONE) by a team of researchers from the Faculty of Life Sciences at The University of Manchester can now confirm that the existence of DNA in amber fossils is highly unlikely. The team led by amber expert Dr David Penney and co-ordinated by ancient DNA expert Professor Terry Brown used highly-sensitive ‘next generation’ sequencing techniques – the most advance type of DNA sequencing – on insects in copal, the sub-fossilized resin precursor of amber. (more…)

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Jurassic Park molecules?

Enzymes evolved in the lab hold commercial and scientific promise

Whether big, small, slimy, or tall, most animal bodies are symmetric.

Except for sea anemones, starfish, sponges, and the like, animals have bilateral, or right-left, symmetry. Us included.

The bilateral body plan became the norm over eons of evolution. But what about molecules? Have any evolved common structures like a body plan? (more…)

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Better Way to Understand Plasmid Cloning from AddGene

Medical research has been studying molecular cloning for centuries. While many remember the Scottish lambs as the first successful cloning, there have been countless medical advances since then. Many of them are not as evident or dramatic as Molly the sheep, they have been blazing the trail for cloning vital organs, DNA strands and chromosomes in hopes of curtailing or even curing the maladies that plague the human race. Plasmids are at the forefront of this research in hopes they can learn how to insert DNA strands and restructure diseases or ailments on a molecular level.

It is difficult to describe what Plasmid is exactly. Plasmid is a biologically engineered DNA strands that are meant to be used in existing organisms as well as creating new ones. There are many aspects of it used in different ways from molecule cloning, manipulating genes or advancing medical research. Plasmids are circular fragments of double-stranded DNA. Plasmids are used in DNA strands and they can be replicated independently of original chromosomal DNA that created them. While they are mainly used for studying purposes at the moment in biological laboratories, they are meant to advance medical research and hopefully be used to prolong human life. (more…)

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Duplex-sequencing Method Could Lead to Better Cancer Detection and Treatment

During an ice climbing trip to the Canadian Rockies last Christmas, two young researchers from the University of Washington, Drs. Michael Schmitt and Jesse Salk, talked about a simple but powerful idea to get better results when looking at cancer cells. If they could reduce the error rate in DNA sequencing, then researchers could better pinpoint which cells are mutating.

This improvement could lead to early diagnosis of cancer and a better treatment plan once researchers knew which cells were resistant to chemotherapy. (more…)

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Innovation Served on a Napkin: How GTRI Moved a Simple Idea From Inspiration to Fabrication

A ground-breaking innovation, birthed in a sudden flash of insight, is the stuff of legend. Air conditioning, Kevlar, the DNA-replicating process known as PCR (polymerase chain reaction) — each was the product of a Eureka! moment. The list may soon be longer by one, thanks to a wandering mind and a napkin.

When Jud Ready attended an academic conference on materials science in Boston in 2003, he didn’t plan on coming home with the idea for a three-dimensional solar cell, but that’s what happened. (more…)

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Kartchner Caverns: A Living Microbe Laboratory

*In the first extensive genetic survey of microbes living in Kartchner Caverns, UA doctoral candidate Marian Ortiz has shown that some of the cave-dwelling microbes may have anti-microbial and anti-fungal properties.*

In a hole in the ground, there lives a microbe. Actually, there live several microbes. What are they and how do they survive in conditions practically devoid of resources or other forms of life?

Doctoral candidate Marian Ortiz in the University of Arizona’s department of soil, water and environmental science is trying to find out. (more…)

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